Massive Science - Surviving the Anthropocene For centuries, human civilization has impacted the world without any understanding of the consequences. If anything is going to survive what's coming next, it'll have to adapt. How did we get here? What could happen? What needs to change? en-US daily 1 Fri, 16 Aug 2019 00:00:00 EST Inside the political deadlock of establishing Marine Protected Areas in the Southern Ocean Politics and culture collide as signatories argue over preserving fisheries and meeting conservation objectives Deck of a boat with icebergs Deck of a boat with icebergs Seth Sykora-Bodie Antarctica is the coldest, windiest, and driest continent on Earth—a place so raw in its geography and climate that early scientists and explorers were almost magnetically drawn to it in a quest for knowledge and glory. And thankfully, Antarctica’s geographic remoteness has protected its fragile ecosystems from the destructive and widespread development and human activity seen elsewhere on the planet that has caused an alarming 36% decline in global biodiversity since 1970.

However, a growing body of evidence suggests that Antarctica and the Southern Ocean face increasing threats in the near future. A rapidly warming climate is permitting an expansion of both commercial fisheries and tourist activity, all of which threaten this fragile environment - which is also an internationally shared and managed resource - that serves as a refuge for marine species and plays a keyrole in regulating global climate systems

The Ross Sea Marine Protected Areas

The Ross Sea Marine Protected Areas

U.S. Department of State

In response to these threats, the 25 nations who are signatories to the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) have been debating proposals to establish a network of marine protected areas (MPAs) that would balance commercial fishing activity with conservation. In 2009, CCAMLR successfully established the South Orkney Island Southern Shelf MPA, followed in 2016 by the Ross Sea Region MPA, which together (at least until the designation of the latter expires in 2052) protect 1.64 million km2, an area roughly the size of Iran.

Since then, however, the parties have struggled to agree on additional MPAs. At its core, the underlying dispute is whether fisheries should be constrained in favor of conservation objectives. On one side of the debate are countries including the United States, New Zealand, Australia, and France) that cite scientific evidence showing that MPAs can serve as a precautionary tool for reducing anthropogenic pressures on the environment. Used in combination with other fishery management techniques, such as seasonal closures and catch quotas, they provide some baseline protection for nature in case the more traditional approaches fail.

Albatrosses on the Northwest Hawaiian Islands National Monument

President Obama made headlines when he expanded the Papahānaumokuākea Marine National Monument Marine Protected Area in Hawaii

Shealah Craighead via Wikimedia Commons

On the other side are countries such as China and Japan that do not support expanding the network of MPAs. They argue that fishing has not reached a level that might cause Antarctic fisheries to collapse. More fundamentally, these nations are opposed to permanently placing large ecosystems off limits to fishing interests without some documented threat, such as ecosystem collapse or species extinction, or evidence that MPAs are the solution to protecting against these outcomes.

On its surface, this second argument may seem convenient—one that we would expect diplomats to argue because they want access to marine resources. But my doctoral research, which focuses on how CCAMLR participants negotiate and implement management actions, suggests that this type of opposition to MPAs is an authentic and deeply held belief: a true cultural divide.

Based on interviews with participants in CCAMLR meetings, it is not just a position of convenience to argue that MPAs should only be established if there is a scientifically documented threat to a specific ecosystem. Rather, it emanates from a value system that believes the natural environment is to be used for human benefit—one that American, Australian, South American, and many European delegations may struggle to comprehend because the underlying beliefs are profoundly different. It may be the case that no amount of ‘reasoning’ will change this perspective

An iceberg in Antarctica.

Photo by Cassie Matias on Unsplash 

For the past three years, I have been investigating the process by which CCAMLR designates MPAs. Through interviews, surveys, and participatory mapping exercises, I have been documenting the evolution and negotiation of the RSRMPA, assessing the impact of external events and politics on CCAMLR negotiations, probing relationships between delegations, investigating individuals' primary objectives and motivations, and examining the key factors that lead to successful agreements.

Together, these datasets paint a picture of an organization that is undergoing a significant period of institutional growth and learning. As CCAMLR confronts increased pressure on its natural resources, it is being forced to expand beyond its traditional focus on fishery management to implement a more comprehensive ecosystem-based management regime that includes MPAs. This means that CCAMLR is having to construct new scientific, legal, political, and institutional mechanisms needed to support spatial management decisions - for example, new MPA guidelines, research and management plans, and staff support at the secretariat in Australia.

James Eades on Unsplash

Based on all of this work, I suggest two different paths forward. The first is recognizing that the current process in which proponents of MPAs develop proposals and present them to other delegations needs to be re-oriented to more clearly include a more utilitarian view of what should be ‘valued,’ ‘protected,’ and ‘conserved.’ In other words, parties of the CCAMLR must recognize that not all countries conceptualize or define biodiversity in the same way. This does not mean that opponents of MPAs do not see value in nature or are unwilling to set conservation targets and objectives to pursue as a collective group. Following this approach would entail securing ‘buy-in’ from countries that currently oppose MPAs by encouraging them to take greater ownership of the process and final proposals.

Jay Ruzesky on Unsplash

The second path would be to identify a specific “threat” to which each MPA proposal intends to remedy. To date, many delegations have voiced opposition to this because they fear it may set a precedent that undermines the ability of protected areas to serve as precautionary management measures. But clearly articulating the potential for overfishing, or modeling how climate change may affect specific regions, is an actionable step towards implementing broad-scale conservation actions. The very concept of an MPA is one of protection, and by definition, we protect vulnerable species or ecosystems from something that threatens their persistence or current state of being. In short, this is a step towards opponents and one that will provide more science and evidence in favor of establishing new protected areas.

In the meantime, refusing to creatively approach or circumvent these political barriers will only delay the establishment of Southern Ocean MPAs, which is an unacceptable outcome considering the scale of the threats facing Antarctic marine ecosystems, the speed with which global climate systems are changing, and the rate at which species are blinking out of existence.

Seth Sykora-Bodie studies

Conservation ecology


Duke University and CNRS Paris


]]> Tue, 13 Aug 2019 22:06:08 EST We need genetic engineering to stave off climate change-induced global hunger Despite what many say, organic farming will not save us from the worst impacts of climate change women working in a field close up of women working on a farm in southeast asia Devang Mehta Last week the Intergovernmental Panel on Climate Change (IPCC) released its Special Report on Climate Change and Land, a document authored by 107 experts from 52 countries. It warned that “Land is a critical resource."

The main conclusion of the report is that humans already use nearly half of the planet’s land for food production and, as global population levels rise, agricultural land is going to be in very short supply. This is because one of the effects of climate-change will be a decline in agricultural productivity across the tropics, meaning that we will need to cut down forests and convert unused land into farmland. This deforestation will lead to even more carbon emissions, culminating in a vicious cycle of increasing warming. 

The report is a frightening 1,400 page-long prediction of rising food costs and starvation of the world’s poor. In fact, behind all the numbers and probability estimates is one truth that carries throughout — that climate change is going to be especially hard on the poor and on people living in the tropics. The IPCC concludes that as carbon dioxide levels rise and the planet warms, farms in temperate latitudes (i.e. the wealthier countries of Europe and North America) will in fact see an increase in yields

The real damage will occur in the Global South, reducing fruit and vegetable production, causing a decline in the amount of available calories and in the nutritional quality of food available to the world's most at-risk populations. The report concludes that the yields of some vegetables will decline by as much as 30%, and that between 30 and 60% of bean-producing farmland and up to 40% of banana-growing regions in Africa will no longer be viable by the turn of the century. 

As a result, the report says that up to 183 million more people will be at risk of hunger due to climate change and consequent rising food prices. However, in a particularly horrifying graph, the report also finds that the solutions we need to mitigate climate change will themselves lead to a ~20% increase in hunger in Africa, southeast Asia, and India. There just isn’t any good outcome here for people living close the equator — people who number three billion human beings, including most of my family.

And that’s why I came away from the report more frustrated than ever with mainstream public environmentalism and what one policy expert has called, “the empty radicalism of the climate apocalypse."

close up of banana tree

Banana-growing regions of Africa will be hit hard by climate change.

 Arminas Raudys on Pexels

One example of this is the modern environmental movement's love affair with organic farming. Organic farming doesn’t even feature once in the chapters of the IPCC report dedicated to food security. This is because it is one of the very worst ways of farming if your objective is to conserve land. In 2017, researchers working at the Research Institute of Organic Agriculture in Switzerland (an organization partly funded by the organic industry) found that if the world converted completely to organic agriculture, we would need between 16 and 81% more land to feed the planet. 

What can help reduce agriculture’s global footprint? One solution that appears frequently in the IPCC report is “genetic improvement” of crops. The report highlights that increasing food productivity through technological solutions like “new cultivars from breeding or biotechnology” will be an important part of climate change adaptation. In fact, the report explicitly mentions genome-editing crops using CRISPR-Cas9, the very genetic tool that a European court decided to ban just last year and that major environmental NGOs like Greenpeace and the organic farming community oppose on ideological grounds.

It is this fixation on ideological purity by parts of the environmental movement that I take issue with, and that is incompatible with the recommendations of the IPCC. After describing the dire state of global land-use, the latest report also provides some hope by presenting 40 different means of preventing over-use of land due to climate change, eight of which could provide the most benefits. Some of these include measures like maintaining soil health that are common in organic farms. However others like managing cattle-grazing pastures (which can actually sequester carbon) and the genetic improvement of crops are anathema to everyday environmentalism and run counter to organic dogma.

To be fair, some environmentalists say they oppose genetic engineering as part of a general disgust with companies like Monsanto. I find this argument disingenuous. When the IPCC identifies genome editing as a way to adapt to climate change by creating heat and drought-tolerant crops, no agricultural researcher really expects this challenge to be met by Monsanto or DuPont or any of the large multinational seed companies. For one, these companies simply don’t have large market interests in the countries and kind of crops that will be most affected by climate change. This argument also places the developed world and its industries at the center of climate change policy, distracting from the urgency with which the Global South needs new climate-resilient crops. 

close up of hands holding seeds

Climate-ready crops could help ease the suffering of millions of people in the future

 Photo by Markus Spiske on Unsplash

Instead, scientists like me want climate-change ready crops to be developed and distributed for free by publicly-funded trans-national organizations like the CGIAR network, the group behind the Green Revolution that has already had a greater impact on food-security in the tropics than all the large private seed companies combined. And due to the ease of using new genetic tools, we are already seeing such innovation in crop engineering happening in publicly funded labs around the world: from cassava plants making better starch, banana and eggplant resistant to a deadly disease, to rice enriched with vitamins and micronutrients. The vision scientists like me have for climate-smart agriculture includes publicly-funded genome-edited crops developed by our colleagues in local countries, using local crop varieties and compatible with low chemical-input forms of agriculture. This is a vision that I think deserves support from the environmental movement and by the organic farming community, and as the IPCC points out, is necessary if we’re to adapt to climate change. 

One common strand that runs through the IPCC report is the importance of compromise and of deploying a combination of diverse solutions to tackle the problem of climate change and land. In Chapter 1, the report flatly says, “none of these response options are mutually exclusive”, and they really needn't be.

According to the IPCC, we need to combine biotechnology with soil stewardship, to better manage grazing lands while reducing red meat consumption, and to tax greenhouse gas emissions but also prevent them from raising food costs. Instead, activists prescribe childishly quixotic solutions like turning entirely to veganism or to buying only organic produce, that turns climate discourse into a constant battle, pitting cattle farmers against Impossible Foods or plant scientists against organic farmers.

This latest IPCC report reads like an advance obituary for millions of humans living in the tropics. I believe that unless the environmental movement changes course, it will simply have helped write the eulogy.

Devang Mehta studies



University of Alberta


]]> Fri, 09 Aug 2019 00:11:05 EST Climate change is going to upset global food supplies and make Dust Bowl summers look tame Yes, the IPCC report says it's that bad. A dust storm approaches a farm in Texas, 1935. Dan Samorodnitsky The Intergovernmental Panel on Climate Change (IPCC) has released another report that spells out, in minute, devastating detail, what terrible shape Earth is in. Previously, they showed how human activities had wreaked havoc on the planet's species diversity. This new report issued on August 8th reveals how land and water are being abused, making food systems increasingly precarious and increasing the spread of desert and non-arable land.

If you follow climate change news or have been outside recently, you can probably imagine a lot of what's in the report. The rate of soil turning into desert is 10-100x faster than the formation of new soil. Land once suitable for agriculture is becoming sand. Precipitation all over the planet has increased, and extreme weather events have also increased over the past century in part because of this drying out. Unsurprisingly, this also feeds into increased risk of wildfires. 

That's just part of the first data chapter. There's an introductory chapter, two more several-hundred-page-long data chapters, and a summary chapter, along with a summary for policymakers goes on. Here's another example of the not-looming-it's-already-arrived crisis. More and more land has become subject to droughts, despite that increased global precipitation.

A graph showing the increase in population experiencing desertification, increase in dryland areas in drought, and the decrease in inland wetlands.

Y-axis is percent change in the indicated measurement compared to 1961.

There are excellent summaries of the report in any number of outlets. Here's a good one. The most interesting/terrifying part to me comes when discussing food price spikes. It discusses the interconnected-ness of global food supplies. When one important crop region experiences (what used to be) abnormal climate, like in 2012 when US corn growing regions went through a drought, the effect is felt worldwide in changes in food price and availability all over the planet. Shockingly, if you take past extreme weather conditions and model what would happen if they occurred today, the results are catastrophic. I'll just quote (emphasis mine): 

"A study simulating analogous conditions to the Dustbowl drought in today’s agriculture suggests that Dust-Bowl-type droughts today would have unprecedented consequences, with yield losses about 50% larger than the severe drought of 2012 (Glotter and Elliott 2016). Damages at these extremes are highly sensitive to temperature, worsening by about 25% with each degree centigrade of warming. By mid-century, over 80% of summers are projected to have average temperatures that are likely to exceed the hottest summer in the Dustbowl years (1936) (Glotter and Elliott 2016)."

We're going to look back on the Dust Bowl as an enviable reverie of cool, damp weather.

]]> Mon, 05 Aug 2019 13:36:23 EST Teenage activists are leading the fight against climate change Baby boomers are downplaying climate change's risks, so a new generation raises their voice A sign that reads "Wake Up" above a picture of planet Earth on fire, being held up at a protest. Alekhya Maram Standing in front of a group of Denver Pride Climate Strike attendees, Riley Ruff felt both nervousness and excitement swirl in their stomach. “The time is now — to act, to advocate, to use your voice,” Ruff said. “Our existence depends on it.”


A picture of climate activist Riley Ruff taken by Alekhya Maram.

Riley Ruff

Alekhya Maram








Bar Harbor on Mount Desert Island (MDI)

Bar Harbor on Mount Desert Island (MDI)

Alekhya Maram










]]> Tue, 18 Jun 2019 00:00:00 EST The US-Mexico border is making life complicated for green sea turtles How do you protect animals that move seamlessly between jurisdictions? Green sea turtle underwater Green sea turtle underwater Tim Briggs The southern border of the United States has been a focus point for American politics for years, and the 2016 presidential race cast a spotlight on the already controversial region. What the pundits and politicians may not have considered is that borders don’t just affect humans—they also impact the lives of animals that live around them.

Take for example, the entrance to San Diego Bay, which is just twelve miles from the border and Tijuana. There, researchers from NOAA have been looking for a different kind of migrant—green sea turtles. The scientists knew that the turtles spend a lot of time in San Diego Bay, but the key to understanding turtle populations is knowing where they breed.

Green sea turtle at the surface

Tim Briggs

Green sea turtle mothers return to the beach where they were born every time they breed, which is every two to three years. (Over her lifetime, a female green sea turtle lays around 2,000 eggs.) So protecting these beaches is paramount for survival of the turtle population, since urban development near the turtles’ nests can confuse hatchlings. They can mistake lights on buildings for the reflection of the moon and stars on the ocean, often leading them to their deaths.

Researchers in San Diego wanted to know where the green sea turtles lay their eggs, make their nests, and what kind of protections they’re getting where they hatch. The researchers had a few ideas: They guessed it might be Mexico, Hawaii, Costa Rica, or the Galápagos Islands. To track the turtles down, the scientists formed a two-pronged study, starting with satellite trackers. Green sea turtles are ideal for satellite trackers, which don't work underwater, because unlike sharks or fish, they need to come up to breathe. Every time the turtle breaks the surface, the tracker pings its exact location to GPS satellites.

Between 2002 and 2009, 10 females found in San Diego Bay between January and April were outfitted with trackers, in an attempt to catch a female on her way to her nesting beach. Unfortunately, out of the 10, only three left the area for their nesting beaches.

To supplement their data, the researchers compared the genetics of the turtles hanging out around San Diego to turtles living in other locations. They found that 71 percent of San Diego-based turtles likely originated from the Revillagigedo Islands, Mexico; 24 percent were hatched in Michoacán, Mexico; and the rest were split between northwestern Hawaii, Costa Rica, and the Galápagos. 

The trackers told a similar story. One turtle migrated directly from San Diego Bay to the Revillagigedo Islands, a trip which took 90 days. She then spent 230 days around the island of Socorro, off Mexico's western coast. Another turtle followed a similar path at first—but then took a sharp left turn to nest at Michoacán.

The final turtle may have nested in a completely new location, the Tres Marias islands—which aren’t known to house a nesting beach for green sea turtles. The last account of green sea turtles there is from 1899, and research access has been limited. Since 1905, the islands have housed a federal prison, which used to be one of the most infamous in Mexico, but later was used as a stepping stone to release. Research on this island’s possible turtle population has yet to be done.

For these turtles, crossing the border means leaving one set of protections and inheriting another. In the United States, the green sea turtle is protected by the Endangered Species Act, and most mortality in US waters comes through fishing and boat strikes.

In Mexico, there are similar legal protections, but they don’t seem to be enforced. Particularly when green sea turtles are foraging off of the Baja Peninsula in Mexico, poaching of eggs and adults is a big concern. In the 1990s, poaching and incidental by-catch—turtles that die through accidental catch by fishermen—meant as many as 30,000 turtles were dying every year. Egg harvesting for food and medicinal purposes has also been a concern for nesting sites, but new laws in Michoacán have helped to increase their breeding populations from under five hundred females in the 1980s to around 2,000 females as of 2009. (There have been inconsistent reports for more recent population estimates). By migrating as adults to San Diego Bay, the green sea turtles may have found an oasis of safety, at least compared to the high mortality rates of the waters off of the Baja Peninsula.

Green sea turtle underwater

Tim Briggs

Nor are turtles the only migratory animals for whom the Mexican border is an issue. Monarch butterflies migrate to Mexico from all over the United States to escape cold weather and hibernate. While some of the areas in Mexico where they hibernate are protected, development throughout their range has led to large fluctuations and overall decline of Monarch populations. In the midwestern US, for example, expansion of farmlands has led to the loss of the milkweed fields where the butterflies are born. Monarch butterflies are under consideration for threatened status from the IUCN. 

Some of the animals migrating across the southern border are even rarer—a Scientific American article reports on jaguars, who once roamed the southeastern U.S. but now are struggling to push back into Arizona. A border wall, like President Trump is advocating for, could fragment the fledgling population from its larger host in Mexico, preventing growth and limiting possibilities for breeding. 

Unlike a wall, which can stop a big cat from walking over the border, the barrier to a sea turtle’s success as a migrant is more abstract—and it occurs in many places that the green sea turtles live. In the Caribbean, green sea turtles can easily pass through territorial waters of many different countries in a short time. Inconsistent protection can threaten even an otherwise strong population.

Luckily for the green sea turtles of San Diego, Mexico just protected the Revillagigedo Islands as a national heritage site and North America’s largest marine protected area. For at least these migrant mothers, the future's looking up. 

Tim Briggs studies

Marine Biology


Northeastern University


]]> Fri, 14 Jun 2019 00:00:00 EST You're eating, drinking, and breathing microplastics. Now what? What are the health implications of eating 250 pieces of microplastic per day? Kid in a plastic ball pen with only their face showing Kid in a plastic ball pen with only their face showing Anna Robuck A new study led by Kieran D. Cox and researchers at the University of Victoria in British Columbia confirms a logical but cringe-worthy conclusion: humans are consuming plastic. The researchers estimate that humans are eating about 250 pieces of microplastic per day, or roughly 94,000 microplastics in a given year. The average amount consumed varies with age and gender, but the basic premise remains.

Microplastics are tiny pieces of plastics, generally less than 5 mm (one-fifth of an inch) in width. Most consumed by humans are tinier still, frequently in the micrometer range and invisible to the naked eye (25,400 micrometers = one inch). These tiny plastic pieces can form from the breakdown of mismanaged plastic waste over time, or can be directly created for different commercial or industrial applications, like microbeads in facial wash and toothpaste. Synthetic fibers called microfibers can also slough off clothing during the laundry process.

These tiny fragments and fibers have garnered a surge of research attention over the past decade, buoyed by public interest and a continuing stream of viral videos and photos viscerally demonstrating the impacts of plastics on ocean creatures like turtles, whales, and seabirds. The ever-expanding body of research continues to detect plastic pollution in air, water, the deepest reaches of the ocean, and creatures of all shapes and sizes in between.

It was only a matter of time before someone started quantitatively exploring plastic ingestion in our own bodies. But humans are difficult study subjects compared to other organisms. It’s hard to safely and ethically investigate plastics in human subjects, and some of the most obvious screening approaches involve combing through a particularly unappealing type of sample 💩.

Two apples in a clear plastic bag

Life in plastic, not so fantastic. 

Sophia Marston on Unsplash 

Researchers in this study got around some of the challenges of human research by instead focusing on existing, published data. They combed through datasets detailing microplastic counts in honey, salt, alcohol, tap water, sugar, bottled water, seafood, and air, and used these figures in combination with dietary habit data, estimates of drinking water consumption, and data about how much we breathe to arrive at an estimate regarding the number of tiny plastic pieces American children and adults may be consuming via eating, drinking, and breathing.

They found our air, water, and food contain variable concentrations of microplastics, and different ages and genders are likely consuming different amounts of microplastics per day. These results aren’t surprising. Our food system is grossly reliant on plastic at virtually every step of production, transport, and storage. Plastic is durable yet not infallible, and it’s unrealistic to think we can surround ourselves and our food with it and avoid tiny pieces breaking free here and there during its life cycle.

The study’s drinking water findings highlight this particularly well—tap water contains about four plastic particles per liter, while the bottled variety contains about 94 particles per liter. Water is naturally plastic free, leaving just one key variable driving these plastic concentrations (hint: it's the plastic bottle!). 

What may be most surprising about their results is their understated nature. The study focused on food, water, and air, but only included plastic concentrations from food items with rigorous data, meaning that studies had to report exact counts or average concentrations of plastic. The existing studies also had to note what kind of plastic was found in a given sample (fiber, fragment, etc.), and note what methods were used to verify that a given particle was actually plastic. Twenty-six studies met these criteria. 

This means the study only estimates the number of microplastics ingested via 15% of the calories comprising a typical American diet—and the researchers still found hundreds of pieces ingested per day. This approach still leaves out some of the most common and healthful food groups due to limited data, such as meat, vegetables, dairy, grains, and fruits. We still have scant idea what microplastic concentrations are associated with roughly 85% of a typical diet, and that’s cause for concern.

Yet cause for concern shouldn’t be a cause for panic. More than anything this study highlights the necessity for further research and conscientious consideration of our relationship with plastic. As one of the study’s authors pointed out, hazard is much different from risk. We know plastic abounds in the natural environment, and now we know we are consuming it, drinking it, and breathing it. We could be eating plastic and sending it down the drain with each bathroom break. 

Empty plastic water bottle

Brian Yurasits on Unsplash

On the flip side, we could be absorbing plastic bits into our tissues and cells, prompting bodily responses that we haven’t quite picked up on or barely understand. Realistically, something between the two is likely ongoing, but we don’t have enough information to actually identify risks or harmful effects from the information at hand, much less deduce what human plastic ingestion means beyond individual exposure.

Wildlife proxies tell us figuring out how plastic could be hurting us is worth the time and effort—some species are being decimated by plastic, while others seem unfazed or even slightly aided and abetted by plastic exposure. Given our often unnecessary use of single-use and disposable plastics, data outlining the exposure and risk of plastic indulgences, such as that presented in this new publication, will be key to make informed choices. This type of information will likely also provide yet another reason to stymie the burgeoning tide of plastic production and waste choking environments around the globe.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Mon, 10 Jun 2019 20:22:51 EST There's no corner of the globe safe from microplastic pollution These tiny plastic pieces have now been detected on top of mountains, in the soil, and even in your honey person's feet and mountains in the background Rebecca Dzombak When I started my garden last year, I was excited to start digging into the soil at my new home, to pull weeds and plant tomatoes, cucumbers, and peppers. What I wasn’t ready for was what I found in the soil in my backyard: bits of glass, old newspapers, and plastic. Lots of plastic. I cleaned it up as well as I could but I had to wonder what I would really end up eating when I ate my ‘garden fresh’ veggies.

Since plastics became a ubiquitous part of life, they have pervasively made their way into every corner of the globe. For decades, reports of macro- and microplastic pollution in the ocean have been making headlines; pictures of strangled dolphins and sea turtles, albatrosses with stomachs full of plastic, and the infamous Pacific garbage patch that’s roughly the size of Texas have captured the public’s attention. These are memorable examples because they are easy to visualize: the fishing net, the six-pack rings, the plastic bags and water bottles floating near the beach. But arguably the worst plastic pollutants are essentially invisible. They’re called microplastics, and they’re everywhere – in the oceans, in the air, and even in your honey

mound of sand and garbage

The most picturesque places on our planet are now marred by plastic pollution

 Photo by Artem Beliaikin @belart84 on Unsplash

A new study in Nature Geoscience found that microplastics were present in a remote, high-altitude lake in the Pyrenees mountains (southern France), far from congested city centers that are thought to be the source for plastics pollution. The authors sampled atmospheric deposits of microplastics for five months, during both wet and dry weather. Precipitation played an important role in how much microplastic was deposited, with rain and snow dramatically increasing the amount of plastic found. Particles as small as Saharan dust (0.25 micrometers) and fibers as long as 30mm were collected. Perhaps most notably, the rate of deposition was comparable to microplastic accumulation around other major cities.

This isn’t the first time microplastics have been found in otherwise ‘pristine’ natural environments; they’ve also been found in remote lakes in Italy and Mongolia, in floodplain soils in a Swiss nature reserve, and in melting Arctic sea ice. The conclusion is clear: microplastics are being transported through the air, making them a global problem, not a regional pollutant.

Broadly defined as plastic pieces <5 mm in diameter (about 0.25 inches), microplastics come from a variety of sources. You may be familiar with them from an old facial scrub that’s now been banned; those tiny beads made waves when large concentrations of them were reported in the Great Lakes, prompting legislative action. Microplastics can also form when larger pieces of plastic break down. Even though plastic takes a long time to fully degrade, exposure to sun, extreme temperatures, and physical movement can accelerate the process, leaving Earth’s surface littered with tiny pollutants. While at first research focused on plastics in the oceans, studies have expanded to include freshwater systems, soils, and the air

The knowledge that microplastics can be aerially transported like dust or pollen and deposited in any environment all over the world has implications for freshwater systems, soil ecology, and human health – to name a few. They may land in a lake, being consumed by fish or smaller organisms, or simply settling to the lake bed. They might land in a river and be carried out to the ocean, or be incorporated into drinking water. They may just land on the ground and slowly be mixed into the soil. Wherever microplastics end up, though, there are negative consequences.

Depending on the organism, the damage caused by microplastics looks different. For example, a fish consuming microplastic may end up with blocked gills, internal lacerations, and even reduced reproductive ability. An already at-risk coral near a river with high concentrations of microplastic may pick up a disease from a pathogen carried on the microplastic's surface. Earthworms may be unable to grow as large as they should, and soil microbial communities could change entirely due to shifts in their chemical environment. Generally, organisms respond to microplastics for what they are: a foreign stressor in their environment.

We are quickly learning about the huge effect of microplastics on the environment

Oregon State University on Flickr

Because the effects of bioaccumulation (a toxin building up as we move higher up the food chain, e.g., mercury going from fish to humans) for microplastics are still not well-understood, the effects on humans consuming them are difficult to predict. Already, microplastics have been found in mussels, fish, chickens, and honey, just to name a few. Problems from inhaling microplastics can exacerbate existing breathing problems (like asthma or COPD) and irritate the lungs.

Human health concerns with microplastics don’t stop at breathing and eating them; we should also be concerned about the soil. Introducing microplastics changes the basic physical properties of a soil – things like density, nutrient distribution, hydrological properties, and the ability to clump together – and alters its ability to provide ecosystem services, like hosting communities of microorganisms and minimizing erosion. Earthworms, which are critical for mixing up a soil and moving around nutrients, end up transporting microplastics within the soil, effectively increasing their mobility. Pathogens and other toxins (PAHs, PCBs, metals) are introduced to the soil in this way, basically creating a tiny pollution hotspot

This all becomes a problem for people when those microplastics make their way into the groundwater flowing through the soil. Currently, most water treatment plants are not well-equipped to effectively remove microplastics from drinking water, resulting in another pathway for human microplastics consumption. That water can also be used for industrial or agricultural practices, spreading the microplastics over large areas and re-introducing them to soils and waterways. Removing microplastics from the environment is no easy task.

So, what can be done?

Minimizing single-use plastics and recycling everything you can (including old clothes, linens, and shoes) is a very good place to start. Facial scrubs got most of the press back when microplastics first hit the news, but other items with microplastics include toothpaste, dishwasher pods, body wash, and even some make-ups (you can find a list of risky items in your country here). Microbeads are currently banned, but if you have these old products, you should be able to send them back to the manufacturer or to 5 Gyres, a research group committed to reducing microplastics.

Rebecca Dzombak studies



University of Michigan


]]> Sun, 02 Jun 2019 20:55:00 EST By 2100, the ocean will be a different color Incorporating the colored dissolved organic matter responsible for the color change improves the accuracy of climate models The Gulf of Mexico from space, showing sediment running into the ocean and different colors of water The Gulf of Mexico from space, showing sediment running into the ocean and different colors of water Maddie Bender The Caribbean Sea bordering Grand Cayman's Seven Mile Beach is a startling aquamarine color. Over 1,500 miles away, the Atlantic Ocean next to Coney Island is a dark bluish-green. And Bondi blue, the color of the original iMac computer, was named after the teal hue of the Tasman Sea off the coast of the eponymous Sydney beach.

Pollution isn't to blame for these stark differences. As light bounces off and passes through water, it reflects the color blue back to our eyes, but microscopic algae and tiny sediments known as colored dissolved organic matter muddy the metaphorical waters and cause oceans to appear green, red, or brown.

The beach shore in Sydney, Australia, complete with turquoise water

The beach shore in Sydney, Australia, complete with Bondi blue water.

Will Turner on Unsplash 

Now, scientists are trying to use these microscopic sediments to help them better predict climate change.

Ocean color has become a vital metric in climate science in recent years, since it is difficult, if not impossible, to measure surface temperature across the world's vast oceans. Instead, equations relate color to temperature, transforming satellite images into de facto heat maps. Understanding what drives ocean color can then help climate scientists fine-tune their equations.

You may not realize it, but you encounter colored dissolved organic matter, or CDOM, all the time. They're an indicator of soil runoff close to shores and products of living creatures in open water. Think about what happens when you brew tea or leave a rose in a vase for too long. The water starts to turn brown — CDOM causes that color change.

Now, two new studies have shown the important role this organic matter can play in modeling ocean temperature in response to a warming climate.

One model that incorporated phytoplankton and CDOM more quickly picked up ocean warming due to climate change than one that didn’t. And when CDOM was factored into a sea surface temperature model, it increased the amplitude of extreme temperatures, meaning the hottest months become even hotter and the coldest months even colder. These changes resembled observed trends in recent summers and winters, but a strong correlation still means that there's no direct proof that CDOM is to blame. The two studies, published in the journals Nature Communications and Geophysical Research Letters, demonstrate the need for increased surveillance of ocean color as well as climate models that better represent biological processes.

bright green phytoplankton

Phytoplankton and colored dissolved organic matter have important, but underappreciated, roles in determining ocean color

 NOAA MESA Project via Wikimedia Commons

“These studies show that scientists aren’t going to get satisfactory forecasts or models or predictive powers if they don’t incorporate [CDOM and chlorophyll],” says Heidi Dierssen, a professor of marine sciences and geography at the University of Connecticut who was not involved with either study.

“This is incredible new work that they're doing that’s really going to change some of the ways that we've done climate modeling in the past,” she adds.

Ocean modeling is standardized by the Coupled Model Intercomparison Project, an international collaboration among the International Science Council, the World Meteorological Organization and the Intergovernmental Oceanographic Commission of UNESCO. The project's models, updated every few years, are used in reports by the Intergovernmental Panel on Climate Change (IPCC). But for years, these models did not factor in CDOM or chlorophyll, the green pigment that allows phytoplankton to conduct photosynthesis.

Different colors of water along the shore at Point Felix, NS, Canada

Sediment run-off alters the hue of ocean water in Point Felix, NS, Canada

Ron Whitaker on Unsplash 

Climate change affects phytoplankton in clear ways — studies show that phytoplankton die off as oceans warm. With this in mind, Stephanie Dutkiewicz, an oceanographer at the Massachusetts Institute of Technology and lead author of the Nature Communications paper, set out to improve the accepted method of measuring the tiny producers. Previously, the standard had been to estimate phytoplankton using overall ocean color, without filtering for specific ranges. But Dutkiewicz found that determining temperature from blue-green light alone — the color range of phytoplankton and CDOM — made for a finer-tuned model. Starting with data from the present day, the researchers modeled a "business as usual" scenario in which sea surface temperature would rise 3 degrees over the 21st century. The blue-green spectrum model recognized unambiguous climate change earlier and in more regions of the ocean than the standard method for estimating phytoplankton: By 2100, it showed a significant trend in over 63% of the ocean, compared to 31% with the standard model.

“It’s only recently that climate modelers have started incorporating this level of optical complexity into our models, and relatively few studies have been done to look at what impact it has,” says Anand Gnanadesikan, an oceanographer at Johns Hopkins University and lead author of the Geophysical Research Letters study.

Gnanadesikan was aiming to quantify the largest impact CDOM could have on sea surface temperature, a key measure of climate change. To do this, he and colleagues modeled extremes on either end of the spectrum — the hottest and coldest months — with and without colored dissolved materials. The difference between the two models is striking: the one with CDOM increased the amplitude of the seasonal cycle in some regions by over 2 degrees Celsius — an “enormous” amount, Dierssen said.

Dark blue ocean waves

Dark blue ocean waves.

Luis Vidal on Unsplash 

One reason most climate models have not yet factored in CDOM is processing power. The more variables a model incorporates, the slower it runs and the more powerful a computer it needs. But as processing power continues to increase, models are able to become increasingly sophisticated. 

Another reason is that historically, the fields of climate modeling and ocean color have been populated by different researchers without much overlap.

“If I go to an ocean color conference, there might be two or three other climate modelers there, one of whom is Stephanie Dutkiewicz,” Gnanadesikan says. Their work, he adds, is at the interface of these two somewhat separate communities.

The teams of scientists behind the two new studies readily admit their models leave something to be desired. Dutkiewicz says her paper’s model factored in CDOM “quite crudely,” and Gnanadesikan cautions against trusting any one model, since different variables and assumptions lead to different conclusions. Nevertheless, both authors say they hope their models will be used and refined by climate modelers.

“There's a statement which says all models are wrong but some are useful ... and I think that is something to keep in mind,” says Dutkiewicz. “They won't be right, they won't be exactly accurate, but we can use them as a tool to try and understand things that we can't actually go out and measure or monitor.”

Maddie Bender studies

Ecology & Evolutionary Biology


Yale University


]]> Tue, 21 May 2019 00:00:00 EST Climate change is almost too big a problem to study. The solution? Volcanoes. Volcanoes blanketed by tropical rainforests are a natural laboratory to study climate change Erupting volcano with huge smoke plume Erupting volcano with huge smoke plume Cassie Freund There is no owner's manual for planet Earth. It would be convenient if there were, because our planet's climate system works like a massive engine - one that humanity is currently blindly tinkering with by pumping carbon dioxide into the atmosphere. We are now operating at CO2 levels not seen for at least 800,000 years. Scientists faced with the difficult task of trying to predict how these elevated CO2 levels are going to affect life on Earth have recently turned to one of the only forces as powerful as the climate engine: volcanoes.


Greenhouse with plants inside

Greenhouses can only be so big.

Abigail Lynn on Unsplash 



Erupting volcano with smoke plume and lava


 Marc Szeglat on Unsplash 




Tree trunk rings in a log

Tree locked away carbon dioxide in their trunks.

Patrick Fore on Unsplash 



Foggy smoky jungle

Boudewijn Huysmans on Unsplash 


Cassie Freund studies



Wake Forest University


]]> Tue, 14 May 2019 18:01:32 EST Biodiversity loss is the very real end of the world and no one is acting like it Radical, wholesale change is needed right this second and cannot be delayed A car drives through a wild fire during the Jones Fire in Oregon. Cassie Freund At least 1 million plant and animal species are at risk of extinction. That was the conclusion of an Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Global Assessment released on May 6th. Many people were aghast at the IPBES findings, and dozens of excellent summary articles that cover this stunning news have since been written.

But is it really that shocking? Only if you haven’t been paying attention.

Truthfully, I’ve just felt numb about the IPBES findings. I know I’m not the only one. For the past 20 years, scientists have been trying to scream about widespread biodiversity loss without being defeatist, struggling to thread the needle of conveying the urgency about our situation – and what happens to humans when we drive every other living thing on our planet extinct – while still sounding upbeat enough to spur positive change. We toe the line between speaking strong enough to raise the alarm but optimistically enough that people don't get cynical or fall victim to ecological disaster fatigue.

It’s time to cut this crap out. This "traditional approach" to advocating - pleading, really - for change is clearly not working. And our time to avoid catastrophe is quickly slipping away.

"Biodiversity loss" is not just the disappearance of charismatic species like the giant panda and black rhinoceros. It also means that the pollinators we depend on for 75% of our food crops will vanish. Marine fisheries will collapse. Animal that harbor disease, usually kept in check by predators, could explode out of control, putting us at risk of new tick-borne diseases and parasites. And yes, we will lose megafauna like elephants, giraffe, and bison. Your grandchildren won’t believe you when you tell them about the big cats and mighty sharks that once existed on Earth.

The full IPBES report won’t be available for a while, but the Summary for Policymakers, which distills the committee’s findings down to the most important points and identifies actions that must be taken to mitigate some of the future carnage, is available online. It's flat-out dire.

The main conclusion of the report is that humans are changing the natural systems we depend on for life to an “unparalleled degree.”

A gray rhinoceros (rhino) laying on the ground at the Auckland Zoo.

This will not end well for us. No matter where you live, how much money you have, or whether you are even consciously aware of it, nature works for you. Animals, plants, and insects are disappearing from the face of the earth. And contrary to what some may think, we can’t just do a technology and engineer our way out of this.

No place on Earth is safe from human influence. Plastic trash litters both the highest mountains and the deepest ocean trenches on the planet. We have irreversibly altered 75% of Earth's land surface. Two-thirds of the ocean is rapidly changing, mainly through warming and overfishing. We have destroyed 85% of our planet’s wetlands, a critical ecosystem for natural disaster protection. We’ve boiled half of the world’s coral reefs to death in the past 150 years, including 50% of the iconic Great Barrier Reef in just the last three years. And yes, nearly one million species are staring extinction in the face because of things that we – you and I, our friends and neighbors – have done or contributed to indirectly.

If that doesn't scare you, chew on this: biodiversity loss could also decimate our food supplies. Our agricultural system is built on breeds of corn, wheat, and chickens that we have artificially selected to be as productive as possible. But, the same way it’s important to have a diverse stock portfolio, maintaining genetic and species diversity within our crop plants and livestock is important for keeping us fed even when disease or pathogen or say wholesale worldwide climate disaster sweeps through.

According to the IPBES report, at least 1,000 of the 5,631 breeds of domesticated mammals are now threatened (with 559 already extinct as of 2016). And the wild relatives of many crop plants are disappearing from nature as well, hampering our ability to adapt to future climate change.

The inescapable reality is that all of the very bad stuff I just described is happening even faster now than just 50 years ago. And although it is not clear from the headlines, all of this destruction is our fault. 

The uncertain fate of a million species has dominated the news, but the most terrifying part of the report for me was the committee's stark acknowledgement that humanity has now painted ourselves into a corner where our continued existence can only be met through “transformative” changes to our economic, social, and political systems.

If that sounds unlikely to you, join the club.

The international community has made half-hearted attempts at such transformative change before. The IPBES report focuses on two: the Aichi Biodiversity Targets for 2020 and the 2030 Agenda for Sustainable Development. The Aichi targets ranged from goals as simple as, “By 2020, at the latest, people are aware of the values of biodiversity and the steps they can take to conserve and use it sustainably” to ideas as ambitious as, “By 2015, the multiple anthropogenic pressures on coral reefs, and other vulnerable ecosystems impacted by climate change or ocean acidification are minimized, so as to maintain their integrity and functioning.”

A house on a dry farm.

We’ve failed or are poised to fail on about 80% of these targets already. And because biodiversity is rapidly disappearing, the world is actually moving backwards on some of the Sustainable Development Agenda, such as ending poverty and improving human health and well-being.

The "good" news is that there will be no legal ramifications to anyone for this failure, so we can just keep chugging along if we want to. Well, some of us can: Like with climate change, the poorest countries will feel the sting of biodiversity loss long before the rest of us.

I guess the silver lining to this pitch black storm cloud is that we in developed nations hold the power to change things, just as we are the ones who drove it all into the ground. But this will require a truly radical re-imagining of society to create systems that bring environmental externalities into the market, increase financial transparency, and make everything from agriculture to access to education more equitable. Or, as Eric Levitz of New York Magazine puts it, all we need to do to avoid going out in “a globe-spanning murder-suicide” is “to build an international government that recognizes the interdependence of all living things.”

Simple, right?

Cassie Freund studies



Wake Forest University


]]> Sun, 28 Apr 2019 19:18:00 EST With inspiration from shark skin, redesigned oil tanker hulls could keep the oceans clean Safer oil transport through stronger hulls and bio-inspired designs Cargo ship from overhead Cargo ship from overhead Patricia Fernandez Though I didn't know it, this spring while I daydreamed about an upcoming surf trip to the Basque Country, Spain—checking flights, Airbnbs and wave forecasts—a small ignition aboard a cargo ship was threatening my plans. In mid-March, the container ship, Grande America, burst into flames off the northwest coast of France and sank, dropping 2,200 tons of oil, over 2,000 cars, and a combined 80 tons of hydrochloric and sulphuric acid into the ocean. These pollutants soon spread across the entire Bay of Biscay.




Aftermath of the 1989 Exxon Valdez disaster.

U.S. Navy on Wikimedia Commons



Oil rig explosion in the ocean

Skeeze on Pixabay




Cargo ship from overhead

chuttersnap on Unsplash 



]]> Wed, 24 Apr 2019 22:13:06 EST Netflix's Our Planet showed walruses in distress. We need to find what humanity's role is Understanding walrus-human interactions in the past might shed some light on the "walrus scene" A group of walruses haul out on to an island surrounded by ice Darcy Shapiro If you’ve watched the polar episode of the new Netflix documentary Our Planet, you might’ve been traumatized by footage of walruses throwing themselves off cliffs in Russia. This seems shocking, but Ed Yong's recent piece in The Atlantic about the footage featured scientists who are skeptical of the narrative that this is driven by climate change, with shrinking sea ice forcing walruses onto increasingly overcrowded beaches. These bizarre events have happened before, they argue, most notably in Alaska between 1994 and 1996, though no one seems to know why.

There's no question that the Arctic is warming, and that the effects on wildlife are starting to become noticeable. Scientists and indigenous hunters have already seen differences in walrus migratory patterns across the Arctic, with walruses changing when and where they spend time on land for breeding or resting, potentially making them more vulnerable to predators or new pathogens. But researchers say the full extent of the impacts of climate change on species like walruses is, at the moment, still unclear.

A herd of walruses with large protruding tusks sitting next to the water.

Bill Tracey Sr.

In a recent paper published in the interdisciplinary journal Quaternary Research, Xénia Keighley and colleagues argued that the first step toward figuring out what will happen to walruses in the future is understanding human-walrus interactions in the past. And while their paper focused on the Atlantic walrus, rather than on the Pacific walrus featured in Our Planet, global climate change will likely impact both species, making the development of methods for studying the historical ecology of Arctic mammals even more important.

Developing this kind of historical ecology is complicated because the information that's needed to create it is spread out across several different fields of research. Biological research on walruses has largely focused on living populations, seeking to estimate their numbers and understand their behavior in order to better conserve and manage them. Studying walruses in this way gives us only a snapshot of their evolutionary history; we can't know if living populations are truly representative of walrus abundance and diversity in the past. 

Meanwhile, archaeologists and historians have focused on the distant past, largely not concerned with how humans have used and viewed the walrus in modern times, or with the effects these uses have had on walrus population biology.

Keighley and colleagues say that this disciplinary divide has left some gaps in our understanding of long-term human-walrus interactions. We still can't answer basic questions like whether the distribution, abundance, and diversity of walruses has changed over time as hunting practices and pressures have differed, or how walrus behavior has changed previously in response to human disturbances, such as abandoning haul-out sites due to the presence of people. The answers to these questions provide critical information on the future of walruses adapting to climate change. 

A huge group of walruses assemble along a coastline in what's called a haul out.

A walrus haul out

Schoen, USGS 

Ancient DNA recovered from archaeological sites and museum collections, for example, could tell us about the fate of walrus populations in places further south than they live today, when some areas of the North Atlantic were 4-6 degrees C warmer. Did they go extinct or interbreed with other walrus populations? It could also tell us if those "lost" lineages contained local genetic adaptations for things like increased heat tolerance, which would be potentially critical for the long-term survival capabilities of today's populations.

In terms of how walrus behavior has changed in response to human disturbances, Keighley and colleagues suggest comparing stable isotopes from the teeth of living, historic, and prehistoric walruses. Isotopes are variants of elements containing different numbers of neutrons. They're incorporated into an organism's tissues over its lifetime and can provide a "signature" of diet and environment, because they vary between foods and locations. A fine-grained analysis of the stable isotopes in walrus teeth could potentially show differences in the seasonal migrations of walruses, which might be driven by human actions, like hunting, or by changes in the climate (human-caused or otherwise). Knowing the scale of these behavioral changes over time might allow us to predict how much flexibility walruses will have in the face of an increasingly warming Arctic.

A biologist works to apply behavior tracking radios to walruses to better understand how the loss of sea ice may be affecting the walrus. (USGS)

A biologist uses tracking radios to see how loss of sea ice affects walruses in Alaska.


"Atlantic walruses face an uncertain future given recent, and projected, climatic changes in the sub-Arctic regions in which they are found," Keighley told Massive Science. "Using a historical ecological perspective... will help us with explanations and predictions of walrus populations today and into the future."

We can't predict what changes are in store for walruses in the future and we're still not sure what's causing them to climb to the top of cliffs. What is clear from the archaeological record is that we've been interacting with them for thousands of years and that we likely shaped their current population size and distribution through our actions, though to what degree is still unknown. The questions posed by Keighley and colleagues have given us a framework on which to build an understanding of our impact on one inhabitant of the Arctic - an understanding that might allow us to prevent repeats of the now-infamous Our Planet walrus scene.

Darcy Shapiro studies

Evolutionary Anthropology


Rutgers University


]]> Mon, 22 Apr 2019 21:08:24 EST Reducing agricultural carbon emissions will be good for the planet and our stomachs From soil microbes to factory farming, the Green New Deal could radically improve our food system Lauren Sara McKee For any group activity to be successful—whether it's a school field-trip or a country's entire economy—people must be well fed. Our health and well-being depend on quality food, which is why food security is so closely linked to success and prosperity, on both a local and national scale. But as world populations grow, agriculture has become heavily industrialized. This has led to amazing food availability, but has also hurt the environment—impacting not only local water and land resources, but also contributing to the global climate crisis.

There is a real sense of urgency among those who want to protect the planet while also keeping everyone fed. That's why, with as little as 12 years left to prevent catastrophic climate change, Democratic members of the US House and Senate have recently proposed a Green New Deal. The proposed legislation aims to overhaul the American economy, with decarbonization as the primary goal. Through laws and financial incentives, the plan proposes to transition the US to a functional economy that emits zero greenhouse gases. It will address industry, transportation, and also agriculture—a field deeply intertwined with both healthcare and employment

The Green New Deal has gained widespread public support and, unlike previous attempts at climate change legislation, it takes a holistic view of industry in society, including the need for good jobs. But agriculture alone will be a tough industry to tackle. 

In conversations about agricultural emissions, the elephant in the room is a cow. Emissions from cattle farms make up around 40 percent of agricultural methane pollution. A recent study suggests that to forestall climate catastrophe, global production and consumption of red meat will need to be cut by about 50 percent. The Canadian government recently released a Food Guide that encourages people to eat less meat, and it's true that a big swing in consumer preferences would indirectly cause changes in how we farm. But the Green New Deal could target farmers directly with initiatives intended to change agricultural practices, shifting from raising meat to growing crops.

That said, even crop-growing farms have many and varied sources of greenhouse gas emissions. Microbial respiration in soil naturally produces CO2 and nitrous gases—but when plants grow, they take up carbon dioxide from the air and nitrogen from the soil, balancing the cycle. When farmers convert land from forest to farm, biodiversity among animals, plants, and microbes is lost, and this normal processes of biomass recycling get interrupted. When ground is left bare between crops, or turned over during tilling, soil erodes. This limits the land's ability to hold water, and releases further greenhouse gases. But there are alternative land management practices, like no-till farming, that may help reduce these kinds of emissions. (Although there is still some controversy regarding the effect of no-till on carbon emissions, there is at least strong evidence that it's good for soil and therefore good for farmers).

Senate and House Democrats stand at a podium while Representative Alexandria Ocasio-Cortez speaks into a microphone about the Green New Deal and climate change legislation.

Reducing agricultural carbon emissions through the Green New Deal could address issues of animal welfare and food safety as well.

Although still short on policy details, advocates of the Green New Deal suggest that it should focus on the use of 'green' approaches in agriculture. As others have noted, this should include abolishing the factory farming of animals and encouraging investment in more efficient infrastructure that improves land and water footprints. For example, financial incentives could help encourage a mixed crop-livestock model, where a single farm both rears animals and grows crops. Manure from the animals can be used to fertilize the fields, and plant waste from the harvest can be used for animal bedding and bioenergy generation. If the animals are also given feed produced on-site, there's a built-in cycling of biological material (and the carbon it contains), and very little need to import organic or synthetic fertilizers onto the farm. This idea of "circular agriculture" eventually improves the quality of the manure the animals produce, and therefore the soil fertility as well. Legislation in the Green New Deal could help promote this kind of farming by establishing legal limits on chemical fertilizer, either by acre of farmland, or by the amount of crops produced.

But if the goal is true agricultural sustainability, we have to look beyond carbon emissions—animal welfare, food safety, and public health matter too. The preliminary text of the Green New Deal proposal focuses heavily on decarbonization, but this is closely tied with other environmental problems. The good news is that by addressing agriculture's carbon emissions, we'll be fixing a plethora of other environmental concerns too. Take, for example, the widespread use of antibiotics, which has caused the development of dangerous resistance in the environment. Antibiotics are used to ramp up animal growth and protect against disease, to prevent financial loss to the farm. A diversified and circular agricultural business model—where each farm produces more than one type of food product and carbon emissions are low—could mean that producing less meat is still economically viable.

Circular agriculture would also help with the overuse of chemical fertilizers and pesticides. Modern agriculture tends to grow massive fields of only one crop, allowing diseases to spread rapidly—which in turn requires chemical pesticides. These chemicals kill the beneficial microbes and insects in the soil, drastically reducing soil fertility, and ironically promoting the spread of disease, as pests and pathogens develop resistance to the sprays. The infertile soil then requires heavy doses of fertilizer. This often leads to runoff of excess nutrients into local waterways, and an explosive growth of algae and other water plants, reducing the oxygen supply to the water, and killing fish. In contrast, circular agriculture calls for growing different crops together, prolonging soil fertility and reducing disease.

Luckily, science has new solutions to offer too. For almost every environmental problem associated with modern industrial agriculture, there is a strong body of research supporting environmentally benign alternatives. For example, instead of chemical sprays, using biological control agents—like Bacillus and other bacteria, or even some non-pathogenic fungi—can reduce pathogen resistance and also improve soil fertility. 

To forestall climate catastrophe, global consumption of red meat will need to be cut by about 50 percent

 Photo by Agence Producteurs Locaux Damien Kühn on Unsplash

The idea behind “biocontrol” is to exploit the natural tendencies of certain microorganisms to antagonize other species that may be pests or pathogens of plants. I am performing research at the Royal Institute of Technology in Stockholm, Sweden, using microbiology and biochemistry to try to understand how bacteria in the soil can keep plants healthy. The goal is to develop new ways to encourage soil microbes to protect their neighbors. For example, by introducing a new bacterial or fungal species to soil, or by adding  natural compound such as chitin—the complex carbohydrate found in insect exoskeletons and fungal cell walls—we can promote so-called “soil suppresiveness,” which is the ability of the soil and all its microscopic inhabitants to naturally suppress disease in plants.

The biocontrol industry is currently dominated by small-medium sized enterprises (SMEs), businesses that have somewhere between 20 and 350 employees. Few larger companies are investing in biocontrol because, currently, there's not a big market for it. Industry experts believe this is specifically because there has never been any governmental support for biocontrol. The Green New Deal could normalize the use of biological control agents by classifying and regulating them, making them part of the farmer's standard toolbox. This would open up commercial opportunities, enticing larger and better resourced companies to get involved in research and development.

The Green New Deal could also provide subsidies for basic research on biocontrol or even pest-resistant genetically-modified crops. Patents for some forms of genetically-modified plant technology have recently expired, allowing researchers to experiment on new varieties of plants that wouldn't need to be sprayed with chemicals to avoid disease.

Of course, it's not like industrial agriculture set out to damage the environment on purpose. Many of the most unsustainable farming practices result from the tiny profit margins of growing food, which force farmers to maximize immediate yields at the long-term expense of the environment. Unfortunately, so far many of these ‘green’ alternatives still come at a high price. This puts them out of the reach of small farm budgets, and means that larger farms have no incentive to make the switch. 

Although detractors of the Green New Deal suggest that governmental subsidies and regulations might not be enough for the scale of changes needed, there are recent examples of policies successfully shifting behavior. Government subsidies for corn ethanol, for example, led to a massive uptick in production several years ago, suggesting that a well-financed push can be effective in changing agriculture.

Addressing agricultural emissions will be challenging, but necessary to mitigate climate change

 Photo by Eddie Kopp on Unsplash

Certainly no one's suggesting it will be simple. The aforementioned ecological problems all have economic drivers, and it won't be easy to craft fair policies that apply to smallholder farms, local organic outfits, and industrial-scale animal farms. Financial penalties for environmental crimes might only further push smallholder farmers out of business, while failing to rein in large industrial polluters. When working out the specifics of the Green New Deal legislation, policymakers will need to work closely with organisations that represent farmers and their local communities.

But if the Green New Deal takes an appropriately broad approach, it has the potential to massively improve environmental sustainability and social equity in farming. Food security in urban areas, and improved public health through better eating habits, are within reach. New scientific developments could help both farmers and the environment—we just need a little help with the transition. But scientifically at least, it's possible to reduce emissions, pesticides, antibiotics, and disease all at the same time—we just have to remember that a farm is a complex ecosystems, not a simple food factory.  

Lauren Sara McKee studies

Microbiology, Biochemistry, and Agricultural Science


KTH Royal Institute of Technology


]]> Sun, 21 Apr 2019 10:18:58 EST While Congress does nothing, New York City passed its own climate legislation With the Green New Deal stalled, cities are stepping up with their own Maritza Silva-Farrell speaks at a podium outside of New York City Hall in front of a crowd of people. Greta Moran Under a bleak gray sky last Thursday, Maritza Silva-Farrell, the executive director of ALIGN, mounted a podium in front of New York City Hall. She reminded an enthusiastic crowd of labor, environmental, and community organizers of what brought them together —the devastating impact climate change has already had on the city. “We’re talking about 400,000 New Yorkers,” she said, referring to the those living in the city’s floodplains during Hurricane Sandy in 2012. “Their lives changed forever.” 

A couple hours later, New York City passed groundbreaking climate legislation, including the largest mandated pollution reduction in any city in the world, just ahead of Earth Day. “Future generations will look back at this moment and they will think of this as one of the most important bills,” Bill Lipton, the director of the Working Families Party, told the crowd at City Hall. “We are starting to turn a corner.”

The New York Climate Mobilization Act is actually a suite of 10 bills, most notably the landmark 'Dirty Buildings' law. The bill, introduced by New York Councilman Costa Constantinides, mandates that New York’s tallest buildings — those over 25,000 feet — will need to slash their emissions through energy-efficient building upgrades. This targets New York City’s surprising worst polluter — skyscrapers — while also creating thousands of jobs in design, renovation, and construction. 

Remarkably, buildings are responsible for a staggering 70 percent of the city’s total greenhouse gas emissions, and the tallest ones are particularly noxious. Out of New York City’s 1.1 million buildings, 50,000 are responsible for 30 percent of the city’s emissions. “When you hear that number, it blows your mind,” said Constantinides. The new Act requires the tallest buildings to cut their emissions 40 percent by 2030, and over 80 percent before 2050.

Zazie Beetz speaks in front of a podium and a crowd of people in front of New York City Hall in support of climate change legislation.

Zazie Beetz, actor and climate activist, speaking outside of New York City Hall.

Greta Moran

The ground-breaking bundle of legislation is being hailed as a Green New Deal for New York City — and rightly so. The Act is one of the first “to comprehensively set standards to cut pollution at the pace and speed of the climate crisis,” Pete Sikora, an organizer with New York Communities for Change, told Massive Science

Not only does the bill have global consequences, it will also have local impacts. Fewer emissions will likely lower the number of asthma cases in emergency rooms. And, along with the promise of rapid decarbonization, the bill honors another tenet of the Green New Deal: the expansion of good, blue-collar jobs. As New York puts in place more stringent policies, these kinds of jobs will continue to increase in order to handle the retrofitting”. “Many of these jobs will be good, union jobs,” Sikora explained, as unions comprise a strong force in the city’s large building renovation industry. 

But it’s been a long road to get to this point. Though billed as part of a national conversation on emissions, the idea far predates Alexandria Ocasio-Cortez’s push for climate legislation. As far back as 2009, then-Mayor Bloomberg called for legislative changes that would have required energy efficient upgrades in large buildings — but he met with intense opposition from powerful building owners and the real estate industry

“There's nothing new about a Green New Deal. We've called it “climate justice” for decades,” said Eddie Bautista, the executive director of the NYC Environmental Justice Alliance, in his speech at the rally. “We call it a ‘just transition.” 

Costa Constantinides speaks at a podium in front of a crowd of people at a rally for climate legislation. They are standing in front of New York City Hall.

Costa Constantinides, New York City Councilman, speaking outside of New York City Hall.  

Greta Moran

Of course, the new part of the Green New Deal — and regional legislation like New York’s — is that they’ve gained traction. Advocates behind the Green New Deal, the youth-led Sunrise Movement, have just launched an cross-country tour and over 100 town halls to continue this momentum. Their goal is to make the Green New Deal federal law in 2021, when they hope to have friendlier reception in the White House. But for now, local governments are leading the way. The Green New Deal is meant to be federally funded and locally implemented, points out Sophia Zaia, the Pennsylvania state coordinator for Sunrise. The Deal is meant to be a framework and funding mechanism to support regionally-driven action, rather than a blanket set of policies. So, in some sense, New York is merely jumping the gun. But New York isn’t alone. Washington D.C. recently passed a bill that would require 100 percent of the city’s energy to come from renewables. The city of San Jose has mandated that all new buildings are carbon-neutral (producing zero net emissions) by 2020, and Santa Fe has committed to going carbon neutral by 2040. As the Green New Deal meets national opposition, cities might be where climate legislation passes first. 

“It’s not just one piece of legislation,” Zaia said. “It’s going to be an era of climate legislation that is finally going to tackle to this crisis.” 

“We know that what that’s going to look like in each individual community is going to be different.”

]]> Fri, 29 Mar 2019 10:04:20 EST Climate change is causing floods all over the world. Here's what you can do to help People are dying in Mozambique and Zimbabwe, in Nebraska and the Dakotas. And millions more are at risk. Gabriela Serrato Marks Ten days after Cyclone Idai, hundreds of people have been reported dead, and over a hundred thousand people have been displaced in Mozambique, Zimbabwe, and Malawi. Simultaneously, catastrophic floods have covered the Midwest of the United States: floods in Nebraska have caused more than $1.5 billion in damage. And in South Dakota alone, tens of thousands of Oglala Lakota people on the Pine Ridge Indian Reservation are fighting severe flooding that has resulted in a humanitarian disaster.

The situation in the US will not improve anytime soon. NOAA's Spring Outlook predicts flooding in the US could continue for months. Forecasts are for more than a little bit of water: From now until May, parts of 14 states are at a greater than 50 percent risk of major flooding, which NOAA defines as waters that require evacuations and "extensive inundation" of buildings and roads. (Just last year, NOAA's map had no regions with major flooding predictions. In 2017, only a tiny part of North Dakota was predicted to have major flooding.) Altogether, there are 200 million Americans at risk of flooding this spring.

A map of the continental United States that shows regions east of the Mississippi River and California are at increased risk of flooding.


As climate change increases the severity of major storms and floods, people will need to prepare, prevent as much destruction as possible, and assist others in need. Often, disaster relief efforts will need to extend much longer than the storms themselves. Take, for example, what's happening now on the Pine Ridge Reservation: although the tribal emergency management office is coordinating immediate efforts, community organizations will be dealing with the aftermath of the flooding for months — or even longer. People outside the reservation may want to contribute to the long recovery, or to send aid to Idai victims. But what are the best ways to do that? 

Check on friends and family in the flooded area

Floods are incredibly complex. Though it may seem obvious when to worry, there are actually many factors that determine when and where a flood will occur, including environmental characteristics like drought, soil moisture, and streamflow. In a flood situation, pay close attention to local emergency management announcements, especially recommendations to evacuate.

The same goes for checking in with loved ones in harm's way. Kellyn LaCour-Conant, a Coastal Resources Scientist with the Coastal Protection and Restoration Authority in southern Louisiana, and her extended family have lived through Hurricanes Harvey, Maria, Katrina, and several other major storms. Before forecasted weather events, LaCour-Conant's family checks in with each other to make sure all family members have the information and essential supplies they need. They've been in enough storm situations that they "know whose homes are more likely to flood or on higher land so [they] can evacuate if need be." You can check FEMA flood maps by address and read more about hydrological risk for specific locations ahead of storms.

After the storm passes, volunteer to help deliver supplies or clean up — like community members have done in Pine Ridge. "We're a communal society, we view each other as relatives. We're seeing a lot of people taking care of their neighbors," says Ernest Weston, Jr., the director of operations for Pine Ridge Reservation Emergency Relief, a community organization that's working to provide post-disaster relief. Even if you're not physically close, get in touch with people to ask what they need. 

A man loads jugs of water into the trunk of his car.

On the Pine Ridge reservation,  Lester Rowland loads containers of drinkable water into his car. 

 Lt. Col. Anthony Deiss 

Pay attention to media coverage and amplify requests for help

Look to local government social media channels or find local organizations who are disseminating reliable information. They may provide links and guides on where to funnel resources. Be aware of how both media outlets and personal friends are talking about disasters. Communities of color are often labeled resilient. But as Tatewin Means, executive director of Thunder Valley Community Development Corporation (a grassroots non-profit near Pine Ridge) says, "Yes, we can withstand anything that's thrown at us. That doesn't mean it's right."

Donate money before tangible goods. Then, focus donations on requested items

Everyone I talked to agreed that if you are financially able to donate, money is the most helpful contribution. LaCour-Contant says, "Some people prefer to donate tangible goods, because it feels more personal or they like the reassurance of knowing exactly how they’re helping. That’s fine, but please don’t donate things that cause more chaos and headaches." 

In Pine Ridge, Means highlighted the need for philanthropic investments in the community, both for flood recovery and to improve conditions on the reservation in the future. For now, Weston specifically requested five gallon buckets, rain and muck boots, shovels, cleaning supplies, and non-perishable food. This kind of help is "greatly appreciated." (Click here to donate to Pine Ridge Relief or find out more about how you can help.)

Picture of flooding so severe only the roofs of houses are visible.

Flooding in Fremont County, Iowa.

Fremont County, Iowa Emergency Management 

Donate as close to the people in need as possible

Try to donate to community organizations with pre-established connections in the area of need. LaCour-Conant says, "Donating through big, national organizations means there will likely be delays in when that donation actually gets in the hands of someone displaced by climate disasters. Donate to local organizations first—they’re the ones who are on the front lines, know the community, and can mobilize before some big organizations." It can take some research effort to figure out where to donate, but it's worth the trouble to make sure your money is making the largest impact. 

Stay engaged after the immediate disaster is "over"

It's especially important to donate or volunteer even after the news cycle moves on. Massive writer Anna Robuck, whose family in North Carolina was affected by Hurricane Florence, says, "The rebuilding stage is the toughest part. Individuals, community organizations, first-responders, animal shelters, and pretty much everyone in an impacted community will be reeling in some way, and will need huge reserves of energy or resources to get back to normal!" Be aware that some disaster victims also continue to experience mental health struggles, including post-traumatic stress disorder long after the waters recede.

A flooded countryside in Nebraska.

Don't ask, "Why don't you just move?"

Although it may seem risky to live near rivers or coasts, there are many reasons why people people might choose not to move away, such as finances or a deep connection to the place. "This is where I grew up, where my ancestors lived and are buried, where my family is, where my culture thrives, and where I feel safest. I will gladly live and die on the Gulf Coast working to help my community survive." says LaCour-Conant. Remember that natural disasters (and their long-term effects) are often exacerbated by colonialism, unequal distribution of resources, and anthropogenic climate change; the victims of these forces shouldn't be forced to move away

Advocate for better environmental policy and more funding for green building projects

No matter where you are, you can encourage lawmakers to keep climate in mind during all policymaking decisions. Prevention is the key to mitigating the impacts of climate change, but resilient building projects aren't always prioritized. "Keep resilient shoreline development and water quality issues on the ballot and regulatory agenda long before a flood, and well after flood waters recede. If these items are not properly addressed before a catastrophic flood, the clean up is that much worse," Robuck says. Means points out that "being environmentally responsible is expensive in this day and age." Though Thunder Valley wants to build new construction that meets lofty sustainability goals, they need the funding to do so. "Green building is reserved for those in the upper echelons of society, and it shouldn't be that way."

When new climate disasters happen every day, it's easy to think that there's nothing we can do to help. But instead of feeling hopeless, consider taking some of these steps to help communities prepare for—and bounce back—from disaster.

Gabriela Serrato Marks studies

Marine Geology


Massachusetts Institute of Technology


]]> Thu, 28 Mar 2019 14:38:00 EST Mosquito-borne diseases get a boost from climate change Bugs like it hot, and evolve faster when there's lots of carbon dioxide Floodwaters after Hurricane Maria Flooded streets in a town in PR in the aftermath of Hurricane Maria Max Levy We often think of climate change in terms of extreme weather, but the impacts of global warming will extend far beyond natural disasters. Scientists suggest climate change will also make more of the world hospitable to mosquitoes—and the diseases they carry. To make matters worse, new research shows that climate change may also be supercharging mosquito evolution.

Zika, West Nile, and dengue are just a few of the deadly viruses that depend on mosquitoes to spread. Human diseases like these are also carried by animals like birds and rodents, who don't always show symptoms. But if a mosquito bites an infected animal, it can later transmit the disease to other animals, including humans. That's why many disease prevention efforts focus on controlling mosquito populations—a task that's about to become a lot harder.

Bugs like it hot

Mosquito species differ in exactly how, and where, they lay their eggs—but they all like water. Some species lay their eggs in soil, others directly in ponds or in flooded containers. The eggs are sensitive to humidity, and, in the case of soil-bound eggs, heavy rainfall actually causes them to hatch. As climate change makes many places warmer, wetter—and more prone to extreme weather—mosquito habitats are changing. This is spreading diseases to new places, as well as making outbreaks worse in places already afflicted. 

Standing water in Ponce, Puerto Rico after Hurricane Maria

A perfect place to settle down and raise some larvae.

 VOA on Wikimedia Commons

According to a 2014 report by the World Health Organization, more than half of the world is already at risk of mosquito-borne disease. And that number is rising. In a recent study, scientists predict that up to 1 billion more people may become susceptible to mosquito-borne disease by 2080. The study tracked how Aedes aegypti and Aedes albopictus mosquitoes could spread, as rising temperatures provide them new habitats. These species are the most common vectors for dengue, Zika, chikungunya, and other emerging diseases.

These viruses were mainly found in tropical areas, but they've now begun popping up in new places, according to Sadie Ryan, lead author of the study, and professor of medical geography at the University of Florida. “Humans are very good at moving both bugs and their pathogens around the globe,” she said in a press release.

Dengue incidents, for example, have risen 3,000 percent in the past 50 years alone, and the virus continues to spread to new countries. Another study estimated that disease-carrying mosquitoes are expanding their range by over 150 miles every year. In 2016, Centers for Disease Control (CDC) investigated how many US counties had the A. albopictus and reported a 10 percent increase within a single year

The threat has motivated researchers like scientists at the CDC to develop better ways to predict outbreaks. "There has been a lot of work on forecasting,” says Gabriela Paz-Bailey, an epidemiologist at the CDC office in Puerto Rico, where she's responsible for monitoring mosquito-borne diseases such as dengue and Zika.

Paz-Bailey and her family had just moved to the island when Hurricane Maria hit. “We were worried that there could be increases in vector-borne diseases after the hurricane,” she says. Paz-Bailey was particularly concerned about dengue and Zika outbreaks, as both diseases are ongoing threats to the island

Culex mosquito larvae in water

Stagnant pools of water are full of baby bloodsuckers

 James Gathany, CDC from Wikimedia Commons

“There are some theories about strong winds actually reducing the number of mosquitoes shortly after a hurricane,” Paz-Bailey says. But while windstorms do typically kill adult mosquitoes, their eggs can survive. And the standing water tropical storms bring helps insect populations rebound quickly. “Not only the humidity and the moisture, but all the debris that is left after the hurricane provide ideal breeding sites.” 

After Hurricane Florence devastated communities in North Carolina last September, for example, many residents reported a rise in active mosquitoes. Scientists suspect that floodwaters accelerated the hatching of otherwise dormant mosquito eggs found in the soil. Two weeks after the storm passed, an entomologist noted the population of one particular species, Psorophora ciliata, had ballooned by more than 15 times.

This giant mosquito species, affectionately known as 'gallinipper,' infamously delivers a memorable bite that aphoristically “nips a gallon of your blood.” Fortunately, the gallinipper rarely carries dangerous pathogens. But what if it started to? After all, mosquitoes (and viruses) evolve.

Speeding up mosquito evolution

Mosquito species that have been considered no more than annoying may soon become a public health threat. A recent study published in the journal Communications Biology, shows that climate change can actually accelerate mosquito evolution. Matthew Wills, a paleobiologist at the University of Bath, collaborated with scientists in York and Beijing to understand how climate influences the speed of evolution, a process known as speciation.

Mosquitos biting a person's arm

Mosquitos spread a variety of infectious diseases

 CDC/ Prof. Frank Hadley Collins from the  Public Health Image Library

“If we look at the last 195 million years—[back] to when mosquitoes originate—we can see there are times when the rates at which they speciate are much higher than others,” says Wills. The researchers were interested in the effects of temperature, as well as the amount of carbon dioxide in the atmosphere, as climate change is altering both.“We found that there is a link with temperature," Wills says, but surprisingly, "the link with carbon dioxide seems [even] stronger.”

During the study, the team combed through 550 previously published evolutionary family trees. These described different species of mosquitoes, how they were related to each other, and when each split off from their predecessors. But the forest of data was full of contradictions. So the team digitized each tree, and then combined the data to come up with a more comprehensive and accurate "supertree" of mosquito relationships.

The team then used known fossil records and mutation rates to assign dates to major changes in mosquito evolution. Fossil records provided physical evidence, and known mutation rates confirmed how quickly mosquitoes could adapt over time. This revealed a conclusive link: historically high temperatures and carbon dioxide levels both increased the rates of mosquito speciation.

While the researchers aren't exactly sure why, they speculate that increased carbon dioxide rates are good for plants.“We think of [mosquitoes] taking blood meals from us, but many species feed on plants as well.” Wills' team proposes that carbon dioxide bolsters mosquito food supplies, and that abundant resources support more more species, providing the chance for more evolution.. 

According to Wills, diversity in mosquitoes means more avenues for transmitting disease. “More species of mosquito can produce more species of parasites."

To be clear, accelerated evolution does not necessarily mean that all mosquitoes will suddenly fly around with incurable viruses. It just means that there will be more opportunities for mosquitoes to spread disease.

So far, scientists have not found evidence that the speciation rate has already increased. Wills suggests that could happen within a few decades—but it could also occur much more slowly. “Part of the problem is we don't know,” he says. The team’s method looked back at data from the last several thousand years, but it can’t predict the near future. “Of course, it’s a concern." To some extent, exactly when rapid evolution begins is not really the point: Science predicts we'll soon have a problem, whether it happens tomorrow or fifty years from now.

When Hurricane Maria plowed through Puerto Rico, the island suffered, but fortunately, there wasn't a post-storm outbreak of dengue or Zika. That doesn't mean the next hurricane won't bring an outbreak. It's time to treat climate change—and its impact on diseases—like the serious public health threat it is.  

Max Levy studies

Chemical Engineering


University of Colorado Boulder


]]> Tue, 26 Mar 2019 16:27:00 EST Warming oceans cast a chill over New England's sea turtles Recent research suggests warming seas will cause more stranded sea turtles sea turtle on beach a sea turtle with its head resting on the sand Anna Robuck If we ignore the dangerously shifting global climate system, there will be consequences: more extreme rainfall, more intense hurricanes, drier and longer wildfire seasons, and continued sea level rise all loom on the horizon. In fact, extreme weather changes are already being seen around the globe.

But one of the lesser known, already visible impacts of climate change is on sea turtles. A recent paper, led by UMass Amherst doctoral candidate Lucas Griffin, links a rapidly warming Gulf of Maine to increased sea turtle strandings on Cape Cod. 

“We were surprised the results suggested this increase was linked with warmer sea surface temperatures," Griffin says. The scientists originally thought the strandings might be associated with how many young sea turtles hatched. But turtles, it turns out, are just one of many Gulf of Maine species "exhibiting a similar shift in both habitat distribution and in phenology patterns.”

The Gulf of Maine is in crisis: The region is warming faster than 99 percent of the global ocean. Fish stocks are moving north, key food web events like the spring plankton bloom are occurring earlier in the year, and regional waters are staying warmer for longer. Griffin’s team used both machine learning and Bayesian statistical methods—using existing data and probability to quantify uncertainty in inferences—to analyze the relationship between water temperatures and the number of cold-stunned turtles, the potentially lethal turtle equivalent of hypothermia. The innovative approach confirmed what local naturalists and wildlife biologists had been observing for years: Warmer waters in the region actually lead to an increased threat of cold-stunning.

While it sounds counter-intuitive, warmer water in October and November encourages the turtles to stick around longer before heading south. Turtles can then become trapped in the arm of Cape Cod as they start their migration, where they face an increased threat of cold-stunning if colder weather sets in.

a map showing the arm of cape cod wrapping around the cape cod bay

Cape Cod sees the largest number of cold-stunned turtles in the northwest Atlantic, as turtles become trapped in the crook of the Cape  seeking warmer waters. 

  Center for Coastal Studies 

Sea turtles are reptiles and poikilotherms, meaning they can’t regulate their internal body temperatures the way warm-blooded mammals can. In a cold snap, as soon as waters drop below around 50 degrees F, their body temperatures plummet and they sink into a sluggish torpor. It's a terrible spiral: their circulations slow down, their heart rates decrease, and they often float limply at the surface, making them more prone to predation or boat strikes. This listlessness prevents turtles trapped by the landmass of Cape Cod from finding a way around the arm of the Cape, making them increasingly vulnerable as the continued chill of December and January move in. 

Griffin suggests that warmer Gulf of Maine water may also be allowing juvenile turtles to shift further north in their range, putting turtles in thermal habitats they are not entirely prepared for. 

Cold-stunned turtles often wash up on regional beaches, dead or very sick — Kemp’s Ridley turtles are most prone to this misfortune. Regional wildlife centers and aquariums like the New England Aquarium shoulder the lengthy rehabilitation process for those turtles still alive, gradually warming them to allow their immune system to keep pace. 

A Kemp's Ridley sea turtle

Kemp's Ridley turtles are the smallest of the world's sea turtles and the most prone to cold-stunning events in the northwest Atlantic.  

 NOAA Fisheries 

If cared for, many do survive and can be released in southern waters, with rehabilitated individuals later showing up on nesting beaches in following years.  Those that don’t make it head for the necropsy table, providing scientists like Griffin key insights about the species. 

His results suggest these strandings will get worse. By 2031, as many as 2,300 Kemp’s Ridleys turtles could strand themselves every year. That's a significant number for the the most endangered sea turtle species in the world. The species has been decimated by poaching, interactions with shrimp trawlers and other fishing boats, and both human and predators consuming their eggs. There are now only around 12,000 Kemp’s Ridley nests laid per year, down from an estimated 121,517 nests in 1947. With such a low number of nesting individuals, increased strandings could further endanger the species.  

While the cold-stunning season is likely over for this winter in Massachusetts, sea turtles can be at risk in any shallow water habitat that experiences precipitously plummeting temperatures — Kemp’s Ridley turtles have been seen stunned in Florida and even along the Gulf of Mexico. As climate continues to shift and extreme temperature fluctuations become more common, these stranding events may change in distribution or frequency around the globe. 

But Griffin and his team remain optimistic about future turtle conservation, emphasizing the need to keep up with rehabilitation and conservation efforts. “Currently, the nesting population has rebounded quite substantially since the 1970’s," says Griffin, pointing out that interventions that helped preserve nesting habitat and minimize human contact were successful. But improvements in turtle populations have, for no clear reason, dropped off over the last ten years. "We need to do everything we can to preserve this species,” says Griffin. 

a turtle floats on shallow water

A cold-stunned turtle floats on the ocean surface, vulnerable to predation and boat strikes. 


While the larger issue of climate change requires sweeping cultural and economic action, you can do your part to help the climate, and sea turtles, by mindfully choosing climate-friendly actions and products. And if you live on the coast, keep an eye out for cold stunned turtles during fall and winter months. A cold-stunned turtle is a vulnerable turtle, and needs professional attention — your warm bathtub will hurt the creature more than help it. If you see a stranded turtle, contact your local wildlife authority to get the turtle into specialized care as soon as possible. 

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Thu, 21 Mar 2019 10:29:00 EST How shadowy tax havens skirt conservation efforts Dark money foreign investments may bankroll deforestation and overfishing Deforestation with close up log Deforestation with close up log Cassie Freund Dark money, a term usually applied to opaque political donations, is also a serious problem for our planet's biodiversity. The 2016 release of the Panama papers, hailed as "history's biggest data leak," was followed less than two years later by an even larger document dump called the Paradise Papers. These events revealed the secrets of how the rich and well-connected exploit legal loopholes and international tax havens to protect their wealth. But an investigation into the data by Victor Galaz and his colleagues from the Stockholm Resilience Center highlights just how the shadowy corners of the global economy extend into the protein on our plates and the air we breathe.

The political and economic ramifications of the papers, and tax havens in general, has been relatively well-studied. But Galaz and his team were most interested in the environmental consequences of our opaque global financial system. They used publicly available data from the International Criminal Police Organization (INTERPOL) and other sources to uncover how secret financial dealings fuel two major conservation threats: overfishing in the world's oceans and deforestation of the Brazilian Amazon.

Illegal, unreported, and unregulated (IUU) fishing is a serious cause of declining fish populations worldwide. This illicit industry, accounting for up to $23.5 billion per year, is also a substantial contributor to the global economy—making it ripe for corruption. Galaz and his colleagues found that 70 percent of fishing vessels involved in IUU fishing are registered in tax havens, mainly Belize and Panama. By contrast, just 4 percent of all legally registered fishing vessels originate in tax haven nations. 

Purse seine type fishing boat in the Indian Ocean with empty nets

Fishing boats with "flags of convenience" easily dodge government regulations 

Jiri Rezac on Wikimedia Commons

Registering a fishing boat in a tax haven isn't a crime, per se. The problem is that Belize, Panama, and many other tax haven countries are also "flags of convenience" states. These are countries with lax or nonexistent law enforcement, making them attractive to shipowners who want to use their vessel for illegal fishing. A ship registered in a FOC state can easily escape the regulations that prevent environmentally destructive activities, like surpassing catch quotas or taking endangered species. IUU fishing can also have downstream effects on seabird, turtle, and other wildlife populations.

Galaz and colleagues also examined the connections between tax and Amazonian deforestation. They used publicly available data from the Central Bank of Brazil to track foreign investment in Brazil's soy and beef industries, which are responsible for much of the deforestation in this region of the Amazon.

They found that 68 percent of foreign investment into the nine biggest soy and beef companies between 2000 and 2011— worth $18.4 billion—was funneled through tax havens. The magnitude of shadowy investment into these two rainforest-destroying sectors is strikingly disproportionate to the total amount of foreign investment flowing through tax havens into Brazilian industry generally—which was just 17 percent in 2011. And almost all of the dark soy and beef money entering Brazil originated in the Cayman Islands, one of the most notorious tax havens in the world.

Tree removal burn in Mexico

There used to be trees here.

 Jami Dwyer on Flickr

One shortcoming of this study, as the authors note, is that it is currently impossible to prove that this foreign investment from tax havens is directly causing deforestation. As the Panama and Paradise Papers showed, the global financial market is a tangled web of secret transactions and offshore bank accounts, which makes tracking money from a foreign source to specific local expenditures challenging.

However, it's not hard to make a logical connection between tax evasion and Amazonian destruction. Less money paid in taxes means a company has more funds available for business costs. In the soy or beef industry, this means greater expanses of tropical forests clear-cut and converted to pasture and crop land. Poor government oversight contributes as well. Enforcement of environmental laws in Brazil has relaxed in the past couple of years, and even beef companies that have committed to stop deforestation on paper cleared some 32,000 square miles of the Amazon for pastureland between 2010 and 2015.

I've been studying and working in biodiversity conservation for almost a decade, and before reading this study, I thought I understood the global drivers of biodiversity loss. Had someone previously asked me whether our current opaque global financial system was in the top five, I might have said no. But I was wrong. We're just now beginning to learn how closely the financial industry enables dubiously legal—and flat-out illegal—environmental destruction. 

Overhead satellite of deforestation in the Amazon with "fishbone" pattern

There's a lot at stake here.

NASA from Wikimedia Commons

In many ways, this problem is just another form of the age-old tragedy of the commons: One person or company profits by taking more than their share of resources at the expense of everyone else. Unfortunately there's a lot at stake: The collapse of vast marine and tropical forest ecosystems would have catastrophic consequences for humanity. 

The saving grace for biodiversity is that improved financial transparency is possible. Policy changes, like a proposed law requiring British territories—like Bermuda and the Cayman Islands—to publicly list the owners of international companies registered in these states would be a good first step toward stopping tax evasion. And it would have a myriad of other political, economic, and social benefits too, like decreasing economic inequality and mitigating the human costs of climate change. All the more reason to work toward shedding a light into the dark corners of the world economy.

Cassie Freund studies



Wake Forest University


]]> Tue, 12 Mar 2019 20:59:42 EST The UN reports humanity is failing its climate change goals No country on the planet is following the Paris Agreement's plan A man examines a sick sheep laying by a dried up pond (the sheep survives). Michael Graw Despite the danger, there has been little climate change action since the 2016 Paris Agreement—three years later, the world is still on track to exceed the 2°C of warming target by as early as 2040. So this week, the UN is once again sounding the alarm on the unprecedented environmental damage that has proceeded largely unchecked.

In its 6th Global Environmental Outlook report, released today, scientists explore how human actions are threatening the food, water, and natural systems that we take for granted. The report highlights how air pollution from fossil fuels and chemical production kills 6 to 7 million people every year. It underscores the unprecedented scale of biodiversity loss around the planet, which threatens food supplies for billions of people. And it emphasizes the rapid decline of safe drinking water sources around the world as a result of intensive agriculture and chemical contamination.

Throughout the report, the specter of unmitigated climate change looms. Climate change isn't just a problem in itself; it also amplifies existing environmental challenges, making them more difficult to solve. Take overfishing, for example. Warming oceans are bleaching coral reefs, obliterating remaining fish habitats in some of the most productive areas of the oceans. Or consider the depletion and contamination of freshwater resources. Climate change is spurring drought and desertification—and consequently, war and human migration—in the world’s most parched regions, including the Middle East, Latin America, and Africa. Not convinced? Look at air pollution: Larger, more frequent wildfires in arid regions and increasing humidity in wet regions are contributing to smog and multiplying its negative health effects.

Meanwhile, the report emphasizes that 45 percent of all dangerous greenhouse gas emissions are produced by just ten countries—including China, the US, the EU, and India. With the exception of the US, all ten are signatories to the Paris Agreement. But without exception, none of these countries are taking the emissions reduction steps necessary to meet the agreement’s 2°C target.

Smoke rises from the floor of a forest after a wildfire.

Photo by Joanne Francis on Unsplash

So will this bleak picture spark action from governments when past agreements and reports have failed? It seems unlikely.

To date, the top emitters have made a lot of noise about climate change, but little meaningful government action. Despite lofty policy statements from the EU, Europe’s greenhouse gas emissions still increased in 2017. Germany and Poland—Europe's two largest sources of coal-fired power—remain far from phasing out their plants. Even policies in China, which has been celebrated as a global leader in reducing emissions, still fall far short of what's needed to keep global temperature from rising above 2°C.

In the US, the Trump Administration has gutted Obama-era emissions goals. They have dramatically increased the rate of public land leases to the oil and gas industry, while simultaneously attacking California’s ability to set more stringent emissions standards than the rest of the country. While some US cities are forging ahead with renewable energy and climate policies, they are most often doing so without the support of—or even in direct opposition to—federal and state governments.

These short-sighted policies are enabled by the fact that there remains little political consequence to ignoring the UN’s warnings. Climate science is often not taught in schools. After the last Intergovernmental Panel on Climate Change report, more than 28 American newspapers did not mention the report on their homepage. As the frequency of extreme weather events increased both at home and abroad, US television news coverage of climate change plummeted in 2018. Climate change was even omitted from reporting on disasters such as wildfires in California, despite overwhelming scientific evidence that greenhouse gas emissions are making these natural events more destructive. In part because of this lack of information, less than four in 10 Americans prioritize climate policy in their choices of elected representatives. 

A woman at a climate change protest holds a sign that reads "Our future's on the line."

Photo by Josh Barwick on Unsplash

The information that does get published tends to focus on quick, individual fixes—biking to work, switching to energy-efficient appliances, or even adding solar panels to your home. But the UN report is a stark reminder that without a national and global appetite for systemic change, the planet faces dire straits. Electricity generation is responsible for one-quarter of global carbon dioxide emissions, and agriculture and deforestation for another twenty percent. Concrete production alone accounts for eight percent greenhouse gas emissions. Climate change won't be fixed by individual actions—the world needs aggressive international policy changes. Accordingly, more than half of the UN report is devoted to discussing emissions policy solutions that can be implemented immediately in countries around the world.

Thankfully, there are small signs of a slow, but critical shift in attitudes. The Green New Deal, though far from a silver bullet, sparked one of the first meaningful discussions over climate change in the US Senate and has pushed the environment into conversations about the 2020 elections. China recently declared renewed efforts to reduce the country's dependence on coal for electricity. And this week, students worldwide are walking out of schools in protest of political leaders not prioritizing reducing emissions. 

Will government leaders, news media, or the public notice? Will they remember any of this in a few weeks, or come time for elections? That remains to be seen. But unless we begin to pressure leaders towards action, it seems likely the UN’s latest warning on climate change will fall on deaf ears.

Michael Graw studies



Oregon State University


]]> Mon, 25 Feb 2019 21:49:06 EST Climate change once heated the oceans and caused "The Great Dying" This time the planet is warming much, much faster pink fish david clode bright pink fish against a black background Elena Suglia Most people have heard of climate change, the long-term and rapid changes in weather patterns Earth is experiencing today. But fewer know that the planet has undergone similar climate changes before—with devastating consequences.

Some 252 million years ago, massive volcanic eruptions spewed greenhouse gases into the sky, trapping heat in the Earth’s atmosphere and warming the planet by more than 10 degrees Celsius. This extreme temperature change occurred over only a few thousand years—a very short time in geologic history. It increased ocean temperatures, deprived ocean-dwellers of oxygen, and triggered what geologists call the “Great Dying” the greatest mass extinction in Earth’s history. 90% or more of marine life went extinct, and terrestrial species didn’t fare much better.

Scientists have hypothesized several ways this drastic climactic change might have prompted the Great Dying, including ocean acidification and metals from the eruptions poisoning a variety of species. But a recent study has unveiled the most likely culprit: The ocean simply became too hot and too oxygen-poor.

In the study, researchers simulated ancient Earth’s conditions before the Great Dying. Then they modeled marine species’ simulated responses to extreme warming. Since testing the model with experiments was impossible, the researchers needed another way to verify its accuracy. To do so, they compared their model’s predictions for how many species would disappear with the actual fossil record of extinct species—and the predictions matched.

Like all studies, this one isn’t perfect. To run their model, the researchers needed to know different extinct species' limits for oxygen and heat. Of course, they didn't have enough data on these species that died of hundreds of millions of years ago. So instead, the authors used data on similar living species. While this isn’t ideal, it’s a clever workaround for several reasons. For one, the climate today is similar to the Permian climate, so species are adapted to similar environments. Secondly, and more importantly, the researchers ran some test runs of their model to show that even if their results are biased, it wouldn't change the general conclusions.

Their study yielded an interesting but counter-intuitive result: Tropical species were less likely to go extinct than those at higher latitudes. The tropics were already hot before the climate changed, so how did marine life handle even more extreme temperatures after rapid warming? The answer is: they didn’t. When conditions become too extreme, tropical species simply migrated to colder latitudes. But species in polar oceans who got too hot were out of luck—there was nowhere colder for them to go!

A floating pool inner tube in the shape of a pink flamingo.

Photo by Vicko Mozara on Unsplash

The events leading up to this ancient die-off share ominous parallels with contemporary climate change: Greenhouse gases trapping heat in the atmosphere, warming oceans, and robbing marine life of oxygen. So far, contemporary climate change has warmed the planet a tenth of the amount preceding the Great Dying. This paper provides frightening context for what the future may hold without immediate intervention. The planet will only continue to warm rapidly if humans don’t act quickly to reduce their reliance on fossil fuels, and reverse global warming to the extent that is possible.

The model predicted the severity and geographic patterns of the Great Dying with impressive accuracy, especially given the lack of precise data. Its success also implies something exciting: Scientists are getting better at modeling large-scale processes. There is a saying among researchers that “all models are wrong; some models are useful.” 

Models like the one used in this study are a valuable tool for projecting present-day species' vulnerability to contemporary climate change, especially because we have a lot more data on existing species and current climactic conditions than those from eons ago. For example, scientists can alter the model’s input to mirror climate warming scenarios published by the IPCC, and predict how different scenarios may affect life on Earth.

The verdict is in on climate change: it is happening, and humans are driving its quick progression. But what that means for the diversity of life on Earth is still an open question, and the answer is one we collectively have the power to determine. Time is of the essence, but with the help of science-informed climate policy and mitigation, we can reverse climate change and conserve the abundant biodiversity we are fortunate to share this planet with. The story of the Great Dying is set in stone (or fossils)—but the ending of the Anthropocene warming story is up to us.

Elena Suglia studies

Plant Ecology


UC Davis


]]> Wed, 23 Jan 2019 12:38:00 EST Ancient plankton have climate data hidden in their shells Scientists have discovered a new way to use single-celled plankton to estimate large-scale changes in ocean chemistry foraminifer Elisa Bonnin The fundamental laws that govern the nature of matter haven't changed since the formation of the earth. Since chemistry and biology still operate by the same rules, fossil records can provide important lessons about how earth’s climate changed in the past. For example, small changes to the chemistry of coral skeletons can indicate when earth's temperature might have changed before humans were around to observe it. As the earth continues to warm, studying these records can give us some insight into where we're heading. 

Jenny Roberts, a postdoctoral researcher at the Alfred Wegener Institute in Bremerhaven, Germany, is working on fossil records like these. Roberts and her collaborators recently published an article claiming that lithium in foraminifera shells can be used to calculate the pH of past oceans. 

Foraminifera, or "forams" for short, are single-celled plankton that live in the ocean. There are two types: planktic forams, which live in the surface ocean, and benthic forams, which live on the sea floor. Both types of forams make their shells out of calcium carbonate, and most often out of calcite. Calcite is a hard mineral (it's chemically similar to limestone), so when forams die, their shells frequently end up fossilized in the sediments. This—and the fact that forams live all over the world—make their shells some of the most valuable tools used by scientists who study past climates.

Whoa, glad this is microscopic

Scott Fay, UC Berkeley

Generally, researchers try to relate some property of the shell to an environmental condition. Roberts and her lab, for instance, examined the chemical composition of the shells. Calcite is a crystal, which means that its molecules are arranged in what’s called a mineral lattice, a regular structure of calcium atoms connected to each other, like a chain-link fence. When calcite forms, impurities often get caught in the gaps, or end up replacing the calcium atom, in a process known as substitution.

Chemical reactions are often dependent on things like temperature and pH. Because the accumulation of impurities in calcite is, on some level, a chemical reaction—where dissolved materials are being converted into a solid phase—researchers can deduce things like temperature, pH, and the chemistry of the ocean based on the amount of impurities in the shells and how those impurities interact with each other. 

Probably chock-full of forams

Hannes Grobe/AWI

Isotopes, other types of atoms, complicate the picture even further. Atoms are composed of protons, neutrons, and electrons. Normally, an atom has an equal number of protons and electrons, but an atom of the same element can have different numbers of neutrons. For example, the most common kind of carbon atom has 6 protons and 6 neutrons. This form of carbon is sometimes called carbon-12, or 12C, named after the sum of the number of protons and neutrons. But a carbon atom can have 6 protons and 7 neutrons. In that case, the atom is named carbon-13, or 13C. 12C and 13C are different isotopes of carbon. Both of these isotopes are stable, meaning they won't decay with time.

Lithium, an element that can be found in forams, has two stable isotopes: lithium-7, the common form, and lithium-6, a rare form. Roberts used lithium isotopes to calculate pH in what's known as a culture study; she and her team grew benthic forams in a lab with seawater at an altered pH. As the seawater became more basic, the amount of lithium-7 in their shells decreased. This correlation was strong enough that the researchers were able to accurately calculate the pH of seawater based on the shells' isotopes. Next, the researchers went back to look at old foram fossils, using their lithium isotopes to look back in time and calculate past ocean acidity. Using sediment core samples and lithium-7, they calculated past ocean pH as far back as 25,000 years ago.

Worth their weight in gold...if you're a paleoceanographer

Jessica Spear, USGS

Of course, because biology doesn't always do what we'd expect, there are often road blocks and new questions that pop up along the way. In this case, while Roberts found these isotope correlations could be applied to fossil records, her estimated pH differed from results collected using another method of calculating pH from fossils. That method focused on boron-11, a different element, in shell calcite. Further studies will be needed to understand these differences. 

Furthermore, while 25,000 years sounds like a lot, on a geologic scale, it's really not that long—some of the most dramatic climate changes occurred hundreds of thousands to millions of years ago. New research will likely try to find what caused these observed trends, where different methods of calculating pH can be applied, and what conditions might affect or disrupt these equations.

But overall, it's an exciting glimpse into some of the biggest questions we have about the past. The development of a new proxy for calculating ocean acidity gives us a new tool to study past climate changes—and the effect of those changes on the species and ecosystems that existed at the time. The earth has a lot of stories left to tell.

Elisa Bonnin studies



University of Washington


]]> Wed, 16 Jan 2019 12:45:31 EST These corals love the warming oceans Japanese coral communities are expanding in response to warming temperatures, but the effects could be disastrous blue coral Gina Mantica Ocean temperatures have risen an average of 0.13 degrees Fahrenheit per decade, threatening many of the world's coral reefs. Mass bleaching events — caused when corals become thermally stressed and expel the symbiotic algae that give corals their vibrant colors — are becoming more frequent and more severe. A 2016 bleaching event, for example, damaged 94 percent of the coral on the Great Barrier Reef.

New research, however, indicates that not all hope is lost for the world's corals. Researchers found that in some spots, like off the coast of Japan and in the Mediterranean Sea, corals can overtake other species, including seaweed, to establish new habitats. But, at what cost?

Previous research predicted that rising ocean temperatures due to climate change would cause a shift from corals to seaweed in coastal ecosystems. As corals degrade from disturbances such as mass bleaching events, seaweed can enter the habitat and use coral skeletons as substrate to live on. But recent fieldwork suggests that the opposite may be happening: some coastal habitats are beginning to shift from seaweed to corals.

In the Mediterranean Sea, seaweed is usually abundant and corals, historically, cover only about 15 percent of the substrate in the area. But in 2009, researchers discovered that the coral species Oculina patagonica covered more than 50 percent of the randomly sampled 1-square-meter areas at Torre Pirulico in Southeastern Spain. This suggests that a significant shift in community structure took place over just the past few decades.

floating kelp

Not as pretty as corals, but just as important

Shane Stagner on Unsplash

Along those same lines, a study published in September in the journal Proceedings of the National Academy of Sciences suggests that off the southeastern and southwestern coasts of Japan, corals expanded their habitat ranges over the last 60 years in the face of warming ocean temperatures, displacing kelp that was once abundant in the area.

According to the study, led by researchers at the National Institute for Environmental Studies in Japan, these shifts are likely to continue happening not only in Japan, but also in similar coastal ecosystems across the globe.

Dr. Jorge García Molinos, an Assistant Professor on the research team, commented on the phenomenon of coastal community shifts in an interview with Hokkaido University in Japan: "This 'tropicalization' of temperate marine communities is not an isolated phenomenon. It is happening in different places around the world, like in Australia, the Mediterranean, or even in the Arctic where it is called 'borealization' instead... Indeed, it is a natural consequence of climate warming at biogeographical transition zones where multiple species live at or close to their distribution limits, like in our case with the corals and kelps."

To better understand the future effects of rising ocean temperatures on coastal communities, the Japanese researchers then used a model to predict shifts in community structure over the next 15 years. They plugged population survey records from 1950-2015 into their model for different species of kelp, coral, and fish as well as their respective habitat ranges over the years. They also included ocean warming and ocean current trends in their model. 

The researchers' model estimates that fish species will rapidly shift their habitat ranges poleward by 2.5 to 5 miles per year in response to a changing climate, swimming in the direction of both ocean currents and cooler waters. The model also suggests that kelp communities will continue to shrink due to rising ocean temperatures and the presence of these new predators (fish). Corals could then freely expand into these areas, moving in as the kelp communities disappear.

The study stressed that this opportunistic behavior is just one possible mechanism by which coral communities could expand into more northern areas, displacing kelp habitats. The model also suggests that coral communities could expand not only by taking over areas where kelp communities contracted, but also by directly competing with existing kelp communities. Such a direct competition between these two organisms has not yet been recorded, so research is needed to fully understand the consequences of their interactions.

This shift in community structure from kelp to corals might seem great to tourists, like me, who will happily take in the sights of the coral reefs. However, kelp are incredibly important to the marine ecosystem: they are responsible for most of the primary production in the world's oceans.

Primary production occurs through photosynthesis, during which kelp are able to harness sunlight to make energy. Seaweeds, like kelp, form the basis of the ocean's food chain, with other organisms relying on seaweeds for food. Without the primary production of seaweeds, the food chain is broken. Such a disruption could lead to decreases in the populations of other organisms, such as fish, that rely on seaweeds for survival. The consequences continue up the food chain, and could lead to the eventual collapse of the ecosystem. 

coral and fish

Tomoe Steineck on Unsplash

Therefore, while at first glance it appears that the expansion of coral communities, like those described here, are a positive result from rising ocean temperatures, the effects could be disastrous. Changes in coastal community structure and composition in response to climate change pose threats not only to seaweed communities, but also to the functioning of the entire marine ecosystem. While corals are beautiful, without seaweed, the future looks ugly.

Gina Mantica studies



Tufts University


]]> Tue, 15 Jan 2019 11:41:31 EST Climate change is rotting away Greenland's cultural heritage Archaeologists are moving as fast as they can, but the past is slipping away A scientist pilots a drone over the ruins of a stone structure in a grassy field. Julie Hollis I can’t look away from the dead child; his soft, dark hair, his lips partly open, the long, black eye-lashes on those empty sockets. His tiny face is tilted to one side, as if questioning something. The hunters who found this fragile child in a north Greenland cave at first thought he was a porcelain doll. But this little boy is as real as his mother and the six other family members buried in that cave more than five hundred years ago and remarkably preserved in the cold, dry Arctic air for centuries.

I first saw the boy and his family during a visit to the Greenland National Museum and Archives in the capital, Nuuk, where the remains were moved after scientific investigations in Denmark in the 1980s. They are just one of thousands of artifacts that document Greenland's rich history of human migration, preserved so remarkably in the frozen soil, protected by remoteness in a country undisturbed by roads or railways. 

There are around 6,000 registered archaeological sites all over Greenland -- and many thousands more that have yet to be discovered. Stone tent rings, meat caches, foundations, field flowers and cultivated grasses growing where once there was a farm, and even burial sites. These artifacts tell stories that are waiting to be discovered, to be documented, to be understood.

An ancient Greenland arrowhead sits in an opened hand of a scientist who found it.

Roberto Fortuna, Nationalmuseet 

But many of these stories will now be lost before they are even found. They are literally being washed away, according to the stark findings of the few archaeologists working in the Arctic. In 2018, researchers from six Arctic and European countries reviewed the state of Arctic archaeological sites. Their findings, reported in the journal Antiquity, make for grim reading. The Arctic once offered a pristine time capsule for archaeological remains, frozen into the permafrost. But over the past 40 years, the Arctic has been warming at twice the global average, melting of the ice cap is accelerating, and the permafrost along that thin strip of land that holds Greenland’s precious record of human migration and occupation, is defrosting. 

“It’s easy to say that climate change is destroying everything,” says lead author Jørgen Hollesen, senior researcher at the National Museum of Denmark, “but I wanted to know the current scientific status, not just opinion. From the beginning, I wanted to make it based on facts, not emotion.”

Next to a lake ringed by mountains, a scientist sets up a surveying probe.


Roberto Fortuna, Nationalmuseet 

Hollesen and his colleagues' review finds clear evidence that a range of climate-induced factors are deteriorating or destroying archaeological sites across the Arctic; coastal erosion through reduced sea ice, increased sea levels and storm events, warming soils and melting permafrost, increased subsurface oxygen promoting decay and microbial action, increased run off, and increased and changing vegetation. And the rapidly changing natural processes are affecting thousands of sites, all at once.

An example is middens, rubbish heaps of the past containing wood, bones, feathers, and fur that serve as a rich source of information about how people once lived. But middens, such as those at the deserted settlement of Kangeq, near the capital Nuuk, where people lived over thousands of years, are now in decay. The organic remains in the Kangeq middens are turning to mush in the rapidly melting permafrost, and being washed away by increased storm activity.

So how does one begin to deal with these problems? One small start is the REMAINS of Greenland project, a partnership between the Greenland National Museum and Archives, the National Museum of Denmark, and the Center for Permafrost Studies (CENPERM) at the University of Copenhagen. The project was designed to understand the factors controlling preservation of Greenland’s archaeological sites and to develop a baseline to identify and manage sites at risk. Where historically the norm has been simply to document archaeology, the REMAINS project took a holistic view, looking at the whole picture of the environmental and human setting of archaeological remains, past and present. What was the environment in which these people lived? How has it changed? What are the current climate-induced impacts on these sites? 

In a grassy valley, a scientist kneels and pilots a drone, flying against a cloudy sky.

Drones over Greenland.

Roberto Fortuna, Nationalmuseet 

The REMAINS project was also different in being multidisciplinary; the field-based studies involved geomorphologists, plant biologists, geographers, permafrost experts, conservators, archaeologists, and specialists working on high precision drone mapping of sites and spectral analysis of vegetation. As well as documenting the present conditions of sites, compared with historical records, REMAINS scientists installed monitoring equipment to document real-time changes in site conditions.

Comparisons with historical records show that vegetation has increased and changed at many sites. Roots are damaging buried artifacts. In a paper in review, researchers argue that the high levels of soil nutrients at these sites – from past human occupation – are now promoting vegetation growth in the warming soils. And the effects of those warming soils on artifact preservation is clear over a time scale of just a few decades. In the 20th century, Norse sites in South Greenland produced remarkably preserved textiles and leather. “But now,” says Dr Hans Harmsen, curator at the Greenland National Museum and Archives, “if you find a site with even moderately good preservation, it’s a really good find.”

A picture of wet and decaying organic material in Greenland soil.

Wet and decaying.

Roberto Fortuna, Nationalmuseet 

While the REMAINS project has been limited in sample size and duration, says Harmsen, “it has allowed us to establish a methodology, to create a baseline. We want to know what’s happening, at least through a couple of years and a couple of seasonal changes.”

This baseline is a key outcome of the REMAINS project. Now, scientists have some idea which environments are at high risk of dramatic impacts on archaeological sites, and in which deterioration might be slow and gradual, where there is more time. In this way, the scientists hope that the baseline they are creating will allow them, ultimately, to be able to triage known sites; to assess and protect or, if that’s impossible, to excavate valuable sites that are at high risk of being lost.

While these are worthy goals, Harmsen is quick to point out the challenges in making that happen. While Greenland has over 27,000 miles of coastline, and many thousands of archaeological sites, the Greenland National Museum and Archives employs just two full time archaeologists. And while the cross-disciplinary focus has proven productive, that is also a problem in itself. Research funding is distinctly partitioned into human and natural sciences with little overlap.

Two scientists surveying the ruins of a stone house in Greenland.

Another site, not enough scientists.

Roberto Fortuna, Nationalmuseet 

“On paper it looks good,” says Hollesen, “but in practice it’s often difficult to get money for things in between.”

With these challenges, so much yet to learn, and so much environmental time pressure, the tasks ahead seem daunting. Take a kitchen midden, for example, an incredible record of how people lived in the past, how they dealt with changes to their own environment, and containing a wealth of human, plant, and animal DNA evidence. A new technique, called Bulk Bone Metabarcoding, pioneered by Frederik Seersholm and colleagues from Curtin University and the National Museum of Denmark, allows species-level identification of fine-grained material from these deposits. "This gives us, as one example, a bigger picture of the menu of those people," says Harmsen. But there’s no telling what might come out of that one day. We probably don’t yet realize the full potential of what we might be able to unlock, but once it’s gone, it’s gone.”

So, is the general scientific consensus that climatic effects are having a dramatic impact on archaeological sites?

“Yes. Definitely,” says Harmsen.

And given the scale of the problems, how, and where, do we focus our attention? An obvious answer is the new UNESCO world heritage area in South Greenland, which provides a focus, and perhaps new funding possibilities. Inscribed in 2017, the Kujataa site preserves a rich record of Norse and Inuit farming from the 10th century onward. But the threats to the preservation of that record are clear.

Three scientists digging at an archaeological site in Greenland. Two are inspecting a find while a third digs.

Always more work.

Roberto Fortuna, Nationalmuseet 

What would it really mean to lose this cultural heritage? Who should care and who should be doing something about it? If you ask Hollesen, the answer is everyone.

“Cultural heritage is not static. We have to take care of it, protect it. If you want to build a house, you’re required to protect any archaeological remains in the soil, not destroy them. But the whole world is changing the climate, and no one is taking responsibility for this.”

For Greenlanders, their cultural heritage is right there in their backyard, and in their immediate past. In the Nuuk area, families will travel to the same sites every summer where their ancestors hunted, the same sites where the Norse lived. “If we want future generations to have these sites, these opportunities to hear about the past, we need to do something,” says Hollesen. There is a common story that links us all, past and present, and in Greenland that link is tangible… for now.

Julie Hollis studies



Government of Greenland


]]> Tue, 08 Jan 2019 10:00:28 EST Climate is getting more extreme in every possible way From precipitation to the carbon cycle to natural disasters, the outliers are now the norm. Elk Bath A wildfire in the Bitterroot National Forest in Montana, United States. Two elk stand in a stream with a hillside on fire in the background. Coleman Harris The term climate change is often used interchangeably with global warming. But while overall global temperatures are warming, the effects of climate change are not limited to hotter temperatures. (In fact, some locations are forecasted to get cooler.) A historically destructive wildfire season plagued California, while heavy storms set July rainfall records on the east coast of the U.S. That's not to mention 2018's hurricane season. Understanding the underlying statistics can help explain why all the repercussions of climate change can look so different.

This past July was a key example of this kind of variability: record-setting highs across the globe were coupled with devastating extreme weather events like monsoons in India and flooding in South Carolina. Imagine climate as a bell curve, where the height on the curve indicates how often something occurs. Natural things often have this shape, called a normal distribution — examples include adult height, the dimensions of almonds, and proteins found in human blood are all roughly normally distributed. This means that more common values tend to be closer to the average (also called the mean), while much larger and much smaller values are less numerous. For example, the mean height for men is 5’9”, so it’s more likely for men to be between 5’6” and 6’0” tall than it is to meet someone who is 7’ tall. 

A bunch of almonds on a white background.


Mullookkaaran via Wikimedia

The distance values tend to be from the average is called the variance. In distributions with a “flatter” shape, values far away from the average are more likely than in a traditional bell curve. Another way of saying that is that unlikely events are more common in flat distributions, or those with a large variance. For example, if we lived in a hypothetical world with a lot of 4’ and 7’ tall men, the variance of that population’s height would be much larger than the one we actually observe.

Because these curves are easy to understand and translate, climate scientists often use a normal distribution to visualize certain parts of the climate, like temperature, precipitation, and the carbon cycle. These models indicate that most days will have weather closer to average (think "normal" spring and fall weather), while extreme hot and extreme cold weather events happen less often. So, if the Earth is getting warmer, where do all of the recent natural disasters and extreme weather events fit into the picture?

Consider, for instance, the distribution of climate in Nashville, Tennessee — summers are hot, winters are cold, and the average yearly temperature is 59°F. Now, imagine if Nashville suddenly became as warm as Houston, Texas, where by comparison, summers and winters are hotter and the average yearly temperature is 69°F. While temperatures are increased, such a change would not necessarily impact its variance — meaning summers would still be comparatively hotter than winters. Figure 1 (below) visualizes what would happen in this new Nashville climate: There would be more hot weather, including more record hot weather, and far less cold weather than its current climate.

A graph showing the shift from a generally cooler climate to a generally warmer one.

Figure 1: Schematic outlining the effect of an increased mean on the climate and subsequent weather patterns, from the IPCC (2001)  

Coleman Harris

Now, what happens if the average temperature stays the same, but the variance increases? Climate change, after all, doesn't just increase temperatures, it increases the possibility of record-setting heat, cold, rain, and associated natural disasters. (Our current curve, in other words, gets much flatter.) Nashville, for example, is already one of the more variable cities in the United States, with average annual high temperatures of 70°F, and average annual low temperatures of 49°F, a difference of 21°F. This explains why Nashville has freezing winters that drop into the 20s and scorching summers that reach into the 90s. Compare this with a less variable place like that of San Diego, California, which is always warm, or Juneau, Alaska, which is always comparatively cold. Increasing variance, as shown in Figure 2 below, creates record hot and record cold weather into the climate — better pack both a jacket and swimsuit. 

A graph showing an increase in variance of climate events. A bell curve gets flattened.

Figure 2: Schematic outlining the effect of an increased variance on the climate and subsequent weather patterns, from the IPCC (2001)  

Coleman Harris

So, what happens when we combine the two effects? There are not many real-world examples of this happening yet, but Figure 3 (below) shows what we have to look forward to. Average temperatures will get hotter, as well as having more record-breaking heat spikes, as well as far less cold weather. Looking at Nashville again, consider that hot weather would now occupy a much larger portion of Nashville’s bell curve—but temperature is only one factor in observable climate. There are dozens of systems impacted by climate change, such as precipitation, the carbon cycle, oceans, glaciers, and the atmosphere. Each of these has its own well-balanced distribution that is currently threatened by changes to the Earth’s climate. By changing the variance within each of these factors, the changing climate poses a serious threat through powerful natural disasters that have potential to impact millions.

A graph showing both an increase in variance and mean, where a bull curve shifts to the right.

Figure 3: Schematic outlining the effect of an increased mean & increased variance on the climate and subsequent weather patterns, from the IPCC (2001)  

Coleman Harris

Increases to the mean and the variance have already impacted the world today, visible in our recent wildfires, flooding, and heatwaves. While each major disaster cannot be directly attributed to climate change, the increasing intensity and frequency of natural disasters is attributable to changes in the Earth’s climate. If measures are not enacted to curb climate change soon, Earth will continue on its path out of balance — resulting in potentially permanent damage to the planet and a climate distribution unfit for human life. 

Coleman Harris studies



Vanderbilt University


]]> Wed, 05 Dec 2018 10:00:00 EST Even corals deep down on the ocean floor can’t escape humanity's impact Climate change, industrial fishing, offshore drilling, and deep sea mining are all threats to life at the bottom of the sea Sandra Brooke When people think of coral reefs, they typically picture warm, clear waters with brightly colored corals and fishes. But other corals live in deep, dark, cold waters, often far from shore in remote locations. These varieties are just as ecologically important as their shallow water counterparts. They also are just as vulnerable to human activities like fishing and energy production.


In an area 160 miles off South Carolina we deployed Alvin, a three-person research submersible, to explore some features revealed during the mapping. What the scientists aboard Alvin found was a huge “forest” of coldwater corals. I went down on the second dive in this area and saw another dense coral ecosystem. These were just two features in a series that covered about 85 miles, in water nearly 2,000 feet deep. This unexpected find shows how much we still have to learn about life on the ocean floor.


Life in the dark

Deep corals are found in all of the world’s oceans. They grow in rocky habitats on the seafloor as it slopes down into the deep oceans, on seamounts (underwater mountains), and in submarine canyons. Most are found at depths greater than 650 feet (200 meters), but where surface waters are very cold, they can grow at much shallower depths.

Shallow corals get much of their energy from sunlight that filters down into the water. Like plants on land, tiny algae that live within the corals’ polyps use sunlight to make energy, which they transfer to the coral polyps. Deep-sea species grow below the sunlit zone, so they feed on organic material and zooplankton, delivered to them by strong currents.

In both deep and shallow waters, stony corals – which create hard skeletons – are the reef builders, while others such as soft corals add to reef diversity. Just five deep-sea stony coral species create reefs like the one we found in August.





Other important types include gorgonians and black corals, often called “tree corals.” These species can grow very large and form dense “coral gardens” in rocky, current-swept areas. Small invertebrates and fishes use their branches for shelter, feeding and nursery habitat.

Probing the deep oceans







Looming threats

The greatest threat to deep corals globally is industrial bottom-trawl fishing, which can devastate deep reefs. Trawling is indiscriminate, sweeping up unwanted animals – including corals – as “bycatch.” It also stirs up sediment, which clogs deep-sea organisms’ feeding and breathing structures. Other forms of fishing, including traps, bottom longlines and dredges, can also impact the seafloor.




Conservation and management


These are useful steps, but nations can only protect what they know about. Without exploration, no one would have known about the coral zone that we found off South Carolina, along one of the busiest coastlines in the United States. As a scientist, I believe it is imperative to explore and understand our deep ocean resources so we can preserve them into the future.

Sandra Brooke studies

Marine Biology


Florida State University


]]> Thu, 29 Nov 2018 10:22:47 EST We're studying collapsed civilizations so that ours can endure climate change Paleoclimatologists are digging into the connections between the collapse of Maya Civilization and extreme droughts Mayan Ruin A photo of a stepped Mayan pyramid. Brittany Ward Over 1,000 years ago, droughts plagued the Yucatan peninsula. The Yucatan was home to the Classic Lowland Maya Civilization, of pyramids and the number zero fame. Droughts occurred intermittently for centuries, from 200 to 1100 CE. This is an era of Mayan history typically split in two – the Classic (200-800 CE) and Terminal Classic (800-1100 CE) Periods. The droughts coincided with the widespread collapse of the Maya Civilization around 1100 CE.

The first scientific evidence of these droughts was discovered by Dr. David Hodell and other researchers at the University of Florida in 1995, using ancient sediments from Lake Chinchancanab. Since then, the droughts have been a popular example of how extreme climate fluctuations can impact society. However, the magnitude of the droughts has remained an elusive and difficult question to answer. Further, archaeological research has revealed a much more complex history of the Classic Maya reorganization than originally thought, suggesting the droughts were not the only factor destabilizing the Classic Maya. Archaeologists have found evidence that suggest the Maya Civilization experienced social changes including class conflicts, warfare, invasion, and ideological change. 20 years after the discovery of drought evidence in the Yucatan, researchers returned to Lake Chinchancanab to investigate a seemingly simple question: just how dry was it?

In the pioneering Yucatán drought research, Hodell and his team sampled sediment cores from the bottom of Lake Chinchancanab that were thousands of years old. In the core, they found layers of gypsum, a white chalky mineral often used in plaster or cement. Because gypsum can only form in a lake setting when a large amount of evaporation has occurred, presence of gypsum in lake sediments is evidence of periods in the past where lake levels dropped significantly—signs of past drought events.

A photo of a stepped Mayan pyramid with a weathered stone sculpture of a serpent's head in the foreground.

Photo by Marv Watson on Unsplash

Interestingly, archaeological records show that these periods of droughts coincided with sociopolitical unrest in the region, including increased warfare and internal violence of the Lowland Maya. This sediment core from Lake Chinchancanab was the first quantitative link between climate and instability of the Classic Maya.

Hodell is now based at the University of Cambridge, but he and his group are still interested in human-climate connections. In this new study, his team went back to Lake Chinchancanab. The researchers are still focusing on the lake’s gypsum, but now they are looking to the ancient lake water that has been trapped in the gypsum since the droughts. The researchers developed new chemistry and modeling techniques to assess how extreme the Classic and Terminal Classic droughts were. By measuring the chemistry of the trapped ancient lake water, they established ideas for what the chemistry and depth of the lake would have looked like during the droughts. With these constraints, the researchers developed a theoretical model of a lake. They tested different climate scenarios to see how the lake chemistry would respond, until the modeled lake chemistry matched the ancient water in the gypsum. It's the scientific equivalent of turning light switches on and off until you figure out which one is the light you actually want.

The researchers ultimately found that rainfall decreased by 50 percent on average compared to today, and as much as 70 percent during the most intense drought conditions. Humidity decreased by two to seven percent. That decrease in rainfall is the equivalent of Seattle becoming as dry as Tucson. "We don't really know what changes in relative humidity might be in that past, because we never really had a tool to constrain it before," says Thomas Bauska, a co-author of the study and researcher at Cambridge University. "[The results] do tell us that the Yucatan was experiencing dry season conditions during a much longer period of the year."

These new results and techniques can open many doors. Much of paleoclimate research relies on qualitatively studying past climate records rather than measuring past climate. It's useful, but this approach prevents us from asking questions precise quantitative data can raise. It's the difference between saying "wow, it was really dry in 1100 CE" and saying "there was a 50-70 percent decrease in rainfall compared to today."

For example, we can learn a lot from the ancient Maya about human resilience and adaptation to climatic extremes. Previous studies in this region showed that during the first Classic Period droughts, the Maya adapted their agricultural practices by rotating their crops to maize (corn) varieties that required less water, but were unsuccessful at adapting in later droughts. But these results were based on qualitative paleoclimate records; hopefully providing more exact estimates of drought intensity will lead to a better understanding of how the Classic Maya reacted in the face of extreme climatic change.

This civilization flourished in the not too distant past: the demise of the Classic Maya occurred around 900 - 1200 CE (though this collapse doesn't mean the Maya disappeared – the remaining population reorganized and formed new communities). Cambridge University, where this research was done, was founded in 1209 CE. But there's still so much that scientists don't know about Mayan history. More concretely understanding the past climate changes of this region is one monumental step toward understanding how the Maya interacted with their environment

Brittany Ward studies

Geochemistry and Paleoclimatology


University of Waikato


]]> Wed, 21 Nov 2018 12:02:50 EST Fewer crops are feeding more people worldwide – and that’s not good Reduced agrobiodiversity threatens the stability of our whole food system Karl Zimmerer One day last March I talked with Juliana and Elisa, a mother and daughter who farmed just outside the city of Huánuco, Peru. Although they had only one acre of land in this mountainous landscape, they grew dozens of local varieties of potatoes and corn, along with other crops. And they knew each of their varieties by a common name – mostly in their Quechua language.



Karl Zimmerer




Wealthy nations have less-diverse diets




Ironically, rich agrobiodiversity in many low- and medium-income nations supports more standardized and genetically uniform breeding industries in wealthy nations. U.S. and European scientists and seed companies have used the diversity of Andean potatoes and their relativesto create commercial varieties that are the roots of modern industrial agriculture.

How change can promote agrobiodiversity




Heirloom apples, Stroud Farmers Market, Gloucestershire, England.

 Barry W****** on Flickr




Shifting diets




Conflicting trends


Karl Zimmerer studies



Pennsylvania State University


]]> Wed, 07 Nov 2018 10:56:00 EST Our buildings could help reverse global warming, instead of being a major cause Concrete isn't going away anytime soon, but we can engineer it to store more carbon Madison Sankovitz Look around as you go through your day and chances are, you’ll be surrounded by concrete. Worldwide, concrete is the most prevalent building material, but it is detrimental to the environment, contributing significantly to greenhouse gas emissions during the production phase. In fact, cement (a main ingredient in concrete) is the second highest industrial source of carbon dioxide on the planet.

Even though concrete is bad for the environment, it has some advantages. Engineers like concrete because it is durable, requires little maintenance, and gains strength with time. Additionally, it can easily be made into a variety of shapes, is usually the cheapest option, and is made from raw materials that are globally available. In other words, we won't stop using concrete in the near future.

Bernard Hermant

But the situation might not be as grim as it sounds: concrete can absorb carbon dioxide and store it permanently, a process known as carbon sequestration. The absorption occurs at different rates depending on the particular mix of concrete, which is made of water, cement, and sand, rock, or gravel.

Historically, scientists assumed that the amount of carbon dioxide concrete removed from the atmosphere was tiny compared to the gas emissions associated with manufacturing it. However, they hadn't actually tested that assumption until now. A recent study from researchers at University of Colorado (CU) Boulder showed that concrete buildings actually "clean up" some of the mess they make in our atmosphere! Jay Arehart, one of the study's authors, explained that the major motivation for this study was to figure out exactly how much buildings can offset their emissions. He said, "Currently, the built environment is responsible for 40 percent of the United States' carbon emissions. What if the built environment could sequester and store carbon, becoming part of the solution to reversing global warming instead of being a main cause?"

Adriana Souto-Martinez, graduate student and lead author of the CU Boulder study, and her team wanted to find out how much carbon could be sequestered by theoretical concrete mixes over time. What they found was shocking compared to past estimates of concrete emissions and sequestration: 19 percent of carbon dioxide emitted by creating concrete can be re-absorbed throughout the concrete’s lifetime.

The researchers quantified concrete carbon sequestration of 30 different theoretical concrete mixtures. In reality, there are endless recipes that can be used to make concrete, but they chose a limited number based on commonly-used mixtures in building infrastructure. Then they conducted a lifecycle assessment (LCA), which estimates the environmental impacts associated with all stages of a concrete’s life, from raw material extraction through cement processing, distribution, use, repair and maintenance, and disposal or recycling. The authors used an LCA to calculate total carbon dioxide emissions from each of the 30 different concrete mixtures. Finally, they used computer models to find the total estimated carbon sequestration. One of the critical findings from this modeling is that stronger concretes exhibited lower total emissions compared to weaker mixtures, which hasn’t been the case for many previous LCAs.

The Salk Institute

Library of Congress on Wikimedia Commons

This new sequestration estimate depends on engineering parameters like cement type and the shape of the concrete, but it’s an important starting point for this research. Architects and structural engineers make critical decisions regarding the design and specification of concrete mixtures that take environmental impacts into account, but they used to make those choices without any data on concrete's carbon sequestration. In addition to quantifying an average sequestration estimate, Souto-Martinez's study provides the missing data that architectural engineers can use to weigh their options. For example, pieces of concrete that sequester the most carbon do not always emit the smallest amount of greenhouse gases.

Although concrete is not the most environmentally-friendly building material, this study shows that it's not quite as bad as we thought. Studies like this are a starting point for developing more sustainable concrete structures. Because concrete is a major contributor to climate change, changing the way we make concrete will go a long way in helping us maintain both a healthier natural environment and a robust built environment.

Madison Sankovitz studies



University of California Riverside


]]> Wed, 24 Oct 2018 10:55:12 EST These unregulated, potentially dangerous chemicals are probably already in your bloodstream Researchers have known that there are unsafe compounds in our water for decades, but the government is just starting to catch up colorful liquid with bubbles of chemicals Anna Robuck On October 4, 2018, an Ohio firefighter and a former corporate defense attorney filed a class-action lawsuit representing every American citizen with a certain class of chemicals in their blood — about 98% of the US population, all in all.

The chemicals used as criteria in the suit are called PFASs (pronounced "pee-fass"), and are unregulated at the federal level. PFASs are found in the blood of almost all American adults, making a class of chemicals perhaps one of the most unifying American characteristics of our time.

The suit is seeking to make companies that produce PFASs pay for studies that would rigorously track the health effects of the chemicals. We don't have a very clear picture regarding how PFASs impact human health or how the compounds behave in the environment.

What we do know is bad. Some PFASs are associated with cancer, developmental effects, liver problems, and immune system impairment in humans and other species. PFASs are currently wreaking havoc in highly exposed communities across the country, with more uncertain but concerning effects related to low-level chronic exposures across the general population. 

PFASs producers started to realize these risks well before they shared this information to the public, and cooperated with the EPA to phase out the most toxic types of PFAS, called PFOA and PFOS, in the 2000s. PFOS is also restricted by an international agreement, the Stockholm Convention. Other versions of PFASs are still being produced and introduced into the environment at high levels, with uncertain consequences for living creatures.

I grew up in two areas with high PFASs concentrations documented in water. I had no idea they were there until I started pursuing a PhD in environmental chemistry.

Even with this degree, it can be difficult to determine PFAS exposure, though they are literally all around and inside us. How many other Americans unknowingly drink or swim in contaminated water, like I did? According to recent research and modeling, drinking water with unsafe PFASs levels has likely reached millions.

The Environmental Working Group and Northeastern University's Social Science Environmental Health Research Institute maintain a map of PFAS contamination sites and detections across the country


PFAS 101

These pollutants were invented in a burst of ingenious yet short-sighted organic chemistry in the 1940s, and have since come to be known as poly- and perfluoroalkyl substances (PFAS or PFASs, previously PFCs or perfluorocarbons).

A PFAS molecule consists of a chain of carbons with fluorine atoms attached, with some additional specialized atom group thrown in for flavor, called functional groups. There are many iterations of this structure, but they all fall under the PFASs family umbrella because they heavily rely on the carbon-fluorine (C-F) bond.

The C-F bond is one of the strongest bonds in chemistry, and it renders powerless an arsenal of chemical and environmental mechanisms that degrade other pollutants. The basic PFAS structure is so stable that many degradable versions of PFASs, with fewer C-F bonds, get together in the environment to re-form structures with more C-F bonds, making them more stable — and much more toxic. It's like the chemical equivalent of Gremlins, as "friendly" molecules turn ugly under the right conditions.


This characteristic structure also makes PFASs two-faced: The carbon chain doesn’t like to associate with water, but various functional groups are quite chummy with it. This means that PFASs are both water and oil repellant, an extremely valuable quality that has made them extremely popular in consumer, industrial, and military applications.

As a result, PFASs are everywhere: fire-fighting foams, nonstick cookware like Teflon, stain-resistant carpet, water-resistant clothing, food packaging, compostable plates, some cosmetics, and other consumer products that repel oil, grease, or water. They've also made their way into air, rain, household dust, glacier ice, the depths of the ocean, wildlife, surface water, and drinking water.

Humans have not escaped PFASs, as the lawsuit duly notes. PFASs in humans primarily come from food and drinking water. Military personnel and industry workers are more exposed through occupational exposures, associated with military bases and production facilities.

Even worse, children have higher PFAS burdens compared to most adults, because they put lots of PFAS-containing stuff in their mouths, spend more time playing on stain-resistant flooring, and receive a starter dose of PFASs from their moms before birth and during breastfeeding. 

A PFAS turning point?

The recent class action-suit comes at a critical moment, as improved analytical techniques are identifying more contaminated sites around the country while health researchers continue to set acceptable levels of exposure lower and lower.

In June, the Agency for Toxic Substances and Disease Registry (ATSDR), an arm of the Department of Health and Human Services (HHS) issued an updated draft toxicological profile for PFASs. A White House aide reportedly described the document as a “public relations nightmare," as it suggests "safe" levels of PFASs are about 10 times lower than the current EPA drinking water guidelines.

Firefighting foam

U.S. Pacific Fleet / Flickr

The ATSDR report provides minimum risk levels, or concentrations that will likely not translate to appreciable health effects. The new levels are based on health studies that say that PFASs affect the immune system and development at much lower levels than previously thought, particularly for children and other vulnerable people. 

For drinking water, this means acceptable concentrations are around 7 parts per trillion of PFOS and 11 parts per trillion for PFOA, according to Laurel Schaider, a research scientist at the Silent Spring Institute. Right now, the EPA’s 2016 guidelines set an acceptable drinking water concentration for PFOA and PFOS at 70 parts per trillion, about ten times higher than the draft report's thresholds.

But just how tiny is a part per trillion you ask? One part per trillion is about one drop of water in an Olympic swimming pool; by the standards in the ATSDR report, a PFASs exposure greater than approximately two thousandth (0.002) of a drop in the average yearly water intake of an American adult could be considered potentially unsafe. 

Trying to visualize 0.002 of a drop illustrates what sets apart PFASs from the slew of other chemicals in our environment: they are harmful at really low levels, yet millions of people are subjected to them via drinking water and other sources every day.

PFASs on Capitol Hill

The ubiquity of contamination and mountain of uncertainties regarding PFASs effects have spurred legislation in addition to litigation. The PFAS Accountability Act of 2018 and the PFAS Federal Facility Accountability Act of 2018 were introduced to Congress in August and September of 2018. The bills seek to increase and coordinate federal and state level responses to PFASs contamination across the country, and have so far received bipartisan support. 

These resources provide more information and resources if you're concerned about PFAS contamination in your community:

The PFASs saga will continue to play out in Congress and the courts, yet ultimately consumers hold more direct power than many may realize. As public awareness grows surrounding these compounds, some companies are working to remove PFASs from their products. Consumers can continue to demand and seek out PFASs-free products to help remove these chemicals, still understudied and potentially dangerous, from the consumer arena.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Thu, 20 Sep 2018 10:00:00 EST After Hurricane Florence, North Carolina's water quality will go down the toilet Floodwaters contaminated with coal ash, human sewage, and animal waste throw the entire watershed out of balance Florence Eye Anna Robuck In the early morning of Wednesday, September 19, 2018, the Cape Fear River in Fayetteville, North Carolina crested at 61.4 feet – which is about 40 to 50 feet above normal. These extra four stories of water have flooded thousands of acres surrounding the small city, briefly reclaiming some of its historic flood plain in what some are already declaring an 1,000 year flood event (although in reality, this is the second “1,000 year event” within three years).

The Cape Fear River at Fayetteville, NC crested as predicted on Wednesday, September 19th, submerging surrounding lands.

National Weather Service, Advanced Hydrologic Prediction Service/ NOAA

Hurricane Florence landed in Wrightsville Beach, NC as a Category 1 hurricane, downgraded from the fears it would arrive as category 4. Yet the downgrade is misleading. The Simpson-Safir scale used to create these categories only considers sustained wind speed, meaning despite the reduced winds, the storm came ashore with the same formidable amount of moisture. Turns out Florence is not a light packer; the storm dumped about 18 million gallons of rain over the region, depositing 30 to 35 inches of rain in some places. Winds and flooding have already caused at least 32 deaths and serious physical damage to homes and infrastructure.

In college, I worked as a water quality research technician in the Cape Fear River watershed. And while human health and welfare take precedence in this disaster, the Cape Fear river and estuary system is taking a beating too. Dr. Hans Paerl from the University of North Carolina Chapel Hill recently published a study that details just how remarkably hurricanes can impact river and estuary systems.

Paerl’s team used water quality data collected over 20 years within the Neuse River-Pamlico Sound system, directly to the north of the Cape Fear river. They found hurricanes can add major loads of organic carbon, as well as nutrients like nitrogen and phosphorus. These additives may change the ability of the downstream system to store carbon dioxide, an important greenhouse gas. Similar results have been seen in the Cape Fear system using data from 1989 - 2005. These results impact our wallets and stomachs, as hurricane-altered water quality was also found to change the makeup and mass of primary producers—the bottom of the food web—that we rely on for fish and shellfish. 

The nutrients and organic carbon discussed in Paerl’s study come from both natural and human sources. As the river jumps its banks during a storm, it fans out onto its floodplain, picking up dead plant material and nutrients from swamplands and bottom-land forest. But human contamination can make a big difference too: large rain events can overwhelm municipal sewage systems and pump stations, pushing an overflow of human sewage into floodwaters. In the Cape Fear watershed, there are also numerous coal ash disposal pits, where ash left over from coal-fired power plants is stored. These pits can be compromised by flood conditions, adding heavy metals and rare earth minerals to the flood cocktail. Current and historical industrial sites might also contribute problematic pollutants if flooded.

And as luck (or a lack of it) would have it, the Cape Fear watershed contains a high density of concentrated animal feeding operations (CAFOs). The watershed produces an estimated 10 million pigs, 16 million turkeys, and 300 million chickens, along with tremendous amounts of 💩, chock full of nutrients like nitrogen and phosphorus along with fecal bacteria.

Dr. Michael Mallin at the University of North Carolina Wilmington has been studying the Cape Fear watershed for decades. Mallin has identified a host of negative water quality repercussions related to CAFOs even in normal conditions—often to the chagrin or denial of the hog industry. Animal waste is often applied to fields as dry litter or pumped into big pools, called lagoons, intended to facilitate decomposition before being sprayed onto fields. This waste management system is hardly effective in dry periods, as waste from lagoons has been shown to contaminate groundwater and adjacent surface water in streams, causing health issues in adjacent communities.

Hog farms store waste in large pools, and then spray it onto fields of feed crops.

Dr. Michael A. Mallin

“Dumping raw swine waste into open pits and spraying it out on fields is not an effective way to treat nutrient and pathogen-rich waste, it is only the cheapest. Since hundreds of such waste lagoons are on the low-lying Coastal Plain, they are pollution time bombs waiting to go off in this hurricane-prone region,” says Mallin.

Extreme flood events like Florence can cause lagoons to overflow or be swallowed by the swollen river, causing mass contamination of floodwaters with nutrient and bacteria-ridden waste. In 2016's Hurricane Matthew, when the river crested at 52 feet, as many as 14 lagoons were breached. 

It’s now clear communities and CAFOs took a serious beating during Florence. State and independent sources suggest 3 hog lagoons were breached, 2 were structurally damaged, 21 were inundated by floodwaters, and 17 lagoons overflowed, along with municipal sewage spills, at least one coal ash pit breach, and thousands of drowned animals thanks to Hurricane Florence. Despite the degree of damage to hog lagoons, these cesspools don’t even need to be directly breached to contribute their noxious waste to floodwaters. Hog farmers prepare for large rain events by pumping out their lagoons, spraying the material on fields. When the rains arrive, these unabsorbed nutrients and organic material run off into adjacent waterways anyway.

The Cape Fear river and its contributing streams are a nature enthusiast’s wonderland, comprised of unique habitats like hardwood bottomlands, rare freshwater tidal wetlands, and saltwater marsh.

Mary Grace Lemon

Even with the huge volume of rain seen during Florence, the solution to all this pollution isn’t dilution, as the aftermath of previous hurricanes like Matthew, Floyd, or Fran in 1996, demonstrated. The overabundance of nutrients, coupled with loads of degradable wastes, leads to plummeting oxygen levels in the water column. Bacteria simply use up too much of the oxygen dissolved in the water trying to decompose storm-sourced materials. The Cape Fear system is a blackwater system with naturally low dissolved oxygen levels, so storm-induced oxygen depletion can readily lead to dramatic kills of fish and bottom-dwelling aquatic creatures, as seen in the Northeast Cape Fear in 1996. 

It's not just the river system that suffers either. Waste lagoons and human sewage contain high loads of disease-causing maladies, like E.coli bacteria and antibiotic resistance genes. By contaminating the water, these pollutants compromise drinking water sources and add an additional degree of risk to citizens fleeing floodwaters or to clean-up efforts in the aftermath of the storm.

Considering Atlantic hurricanes are projected to occur more frequently, move more slowly, and as result, carry more moisture, watersheds along the Eastern seaboard must start to think critically about their preparedness for 100 to 1,000 year floods. While Andy Curliss, CEO of the North Carolina Pork Council, contends that lagoons across the state can deal with 25 inches of rain, even that may not be enough due to climate change; in the last two years, two hurricanes have dumped 20 to 35 inches of rain in locations across the state.

Florence shattered lives and infrastructure, requiring long-term recovery efforts across a wide swath of the Carolinas. And the long-term water quality and food web ramifications of Florence will only play out in the coming weeks and months.

If you would like to aid relief efforts, check out this list of opportunities compiled by the New York Times, along with efforts endorsed via Michael Jordan’s relief efforts.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Mon, 10 Sep 2018 10:00:00 EST Ancient Romans never reached Greenland, but the emissions from their silver mining did Ice cores, used to study ancient climates, also contain the history of the Roman Empire Elisa Bonnin Of all of the civilizations of the past two thousand years, there are few as well-known as the Roman Empire. At the height of its power, Rome left an indelible mark on the culture, religion and language of Western Europe, and its contributions to world history, literature, and policy can still be felt today. But Rome also left stranger, more subtle marks on the world, besides its monuments and ruins. It left proof of its passing even in ice cores.

A recent study published by Joe McConnell, a research professor at the University of Nevada, and his collaborators shows that lead levels in Greenland ice cores can be traced back to one very specific activity — silver mining. Roman mining techniques extracted silver by smelting lead-silver ores, and adding more lead to the resulting mixture to concentrate the silver. The two metals would be separated later in the process, but this activity, which was usually done at the Roman mines of Rio Tinto in southern Spain, was the major source of lead emission into the atmosphere for that time.


Rob Oo / Flickr

And those emissions can still be seen in ice sheets, which build very slowly over time. When ice forms in Greenland and Antarctica, it records the chemistry of the atmosphere at the time of its formation, a snapshot of Earth's history. As ice sheets continue to build and thicken, those snapshots are preserved in time, like Earth's own historical records, and while these chemical records may not be visible to the naked eye, they are not invisible to modern analytical techniques. The chemistry of ice cores is often used to study past climates, but McConnell and his team turned their attention to something a little closer to home, revealing a cycle of expansion, plague, prosperity and war.

The rise and fall of the Roman Empire is captured in the lead emission record, but while the Romans greatly expanded mining operations in the Iberian Peninsula, they weren't the first civilization to mine in that region. The first sustained increases of lead emissions began around 1000 BC, almost a millennia before the rise of the Empire. This coincides with the high point of the Phoenician civilization, who were expanding into the western Mediterranean. Emissions continued between 400-200 BC, as the Carthaginians continued mining in Spain, but the signs of emissions drop in 264 BC, at the start of the First Punic War.

Hannibal's war elephants in the Second Punic War

Public domain

During the final years of the war, as Carthage struggled to pay off the mercenaries they had hired, emissions ramped up, reflecting an increase in silver mining to keep up with this demand. (Carthage eventually lost to the rising Roman Republic.) Emissions dropped again when mining activities were disrupted at the start of the Second Punic War, but rose when the Republic seized mines from Carthage in 206 BC.

For the first few centuries of Roman rule, mining activities were interrupted by various wars in the region. Warfare in Spain kept emissions consistently low between 108 to 92 BC, and emissions dropped even further after 80 BC, due to the Sertorian War, when a coalition of Romans and Iberians, led by the general Quintus Sertorius, fought against a regime established by Sulla, the statesman who established himself as the Republic's first dictator in a century. Emissions continued to drop after the Sertonian War due to regular Lusitanian raids, only recovering in 61 BC, under the leadership of the governor of Spain, a man whose name is almost synonymous with the idea of Rome — Gaius Julius Caesar.

Caesar (in focus)

Cesare Tagliaferri / Flickr

After Caesar’s successful campaign against the Lusitanians, mining activities recovered, and emissions increased for about a decade. Then, civil wars and the end of the Republic put another stop to mining activities, which only recovered after the victory of Octavian (later the Emperor Augustus) in 31 BC. From there, emissions increased again, remaining high until around 160 AD, with the occasional short-term fluctuations. This coincides with what became known as Pax Romana, the longest period of sustained peace in European history up until that point. However, emissions were ultimately disrupted by the Antonine Plague in 165 AD, a pandemic of either smallpox or measles that lead to the death of five million people, killing up to a  third of the population in some areas and devastating the Roman army. Emissions did not recover until 750 AD, well past the twilight of the Empire.

The link between these historical events and silver mining can be seen not just in ice core data, but in the composition of Rome's silver coin — the denarius. Surviving denarii from periods with low emissions tend to have lower silver content than denarii from high-emission periods. The drop in silver mining after the Antonine Plague ultimately led to the shift of Roman currency away from silver and toward a compound that was essentially a gold-copper alloy.

The Roman Empire existed more than 1,500 years ago, at a time before the Industrial Revolution, but we can still see evidence of their activities in ice cores today. We can watch, using chemical traces locked in ice, the collapse of a Republic and the growth of an Empire. We can see evidence left behind by wars and migrations that we think of as events of the distant past. But the world inhabited by the Romans isn't, ultimately, all that different from the world we live in today. There were years of war and years of peace, commerce, trade and tragedy, all conducted by human beings very much like ourselves.


Markus Trienke / Flickr

The distance between us and Rome might seem immense, and the distance between us and some of the oldest civilizations in the region might seem even larger still, but it's important to realize that as far as the Earth is concerned, this all happened in the blink of an eye. If we condense all Earth's history down into a single calendar year, the Phoenicians, Julius Caesar, and everyone reading this article all exist together in the last few seconds before midnight on December 31. There is an enormous wealth of information about the Earth's past and humanity's history locked up in the ice, waiting for discovery — even though our story only barely scratches the surface.

Elisa Bonnin studies



University of Washington


]]> Mon, 03 Sep 2018 09:06:24 EST How to be a better tourist? Look to the Galápagos Tourism accounts for 8 percent of greenhouse gas emissions. We can do more to limit our footprint, carbon and cultural Jenny Howard Flying on an airplane always gives me a rush, especially when the plane is heading toward the Galápagos. Without fail, the view of turquoise seas and lava rock-edged islands as we descend causes my heart rate to pick up. I've had the opportunity to travel to the Galápagos Islands six separate occasions – six round trip flights between North Carolina and the archipelago – as a part of my PhD research at Wake Forest University. To reach the field site on Isla Española, we take a plane, bus, taxi, and boat – all burning carbon-rich fuel, increasing my carbon footprint tremendously. Although I travel to the Galápagos for research, in many ways I'm still a tourist: I’m not a permanent resident of the archipelago and I buy food from restaurants and souvenirs from local shops, much like a tourist.

"Typical tourists."

Shai Gluskin / Flickr

Protected areas across the globe, like the Galápagos Islands, receive an estimated eight billion tourists each year and tourism is predicted to increase at a rate of 4 percent annually. A new study in Nature Climate Change calculated how tourism increases greenhouse gases that cause climate change; it found that tourism accounts for 8 percent of greenhouse gas emissions, with transportation, shopping, and food consumption being the biggest factors. Unsurprisingly, tourism's carbon footprint increases with increasing disposable income: The US has the greatest disposable income and the largest carbon footprint. Tourism is predicted to increase more than any other economic sector, particularly as the demand for exotic adventures surges. Tourism can provide a huge economic boost local economies, but it can also harm local culture and environment, and contribute to climate change. Should we stop traveling altogether?

Galápagos Islands: A case study

When I tell people where I work, they often exclaim “I would love to visit there someday,” and some have ask if tourism has ruined the Galápagos. I wondered, though the enchanted islands have undeniably changed since Darwin first visited in 1835, could there be any truth to this question?

After 1979, when the Galápagos were designated a UNESCO World Heritage Site, the number of tourists visiting the Galápagos increased to an unsustainable rate – the Galápagos National Park Directorate wasn’t prepared to handle so many visitors. In 2007, the archipelago was placed on the UN's list of endangered Word Heritage sites, but changes in biosecurity measures and conservation efforts resulted in its removal in 2010. Tourism to any place like the Galápagos is a balancing act of benefits and harms, which every visitor should keep in mind before traveling.

Good Practices: Benefits

  • The Galápagos National Park protects 97 percent of the islands; humans (residents and agricultural activity) only occupy 3 percent of the archipelago. Visitors can buy local milk, cheese, and produce meaning those goods don’t have to be imported to the islands (using carbon-rich fuel) from continental Ecuador.
  • The Galápagos National Park Directorate limits the number of visitors to specific tourist-approved sites. For example, Bahía Gardiner at Isla Española can only have, at most, four cruise boats at a time. The park coordinates with approved tour operators on these logistics to minimize the human effect on the local plants and animals.

A log cruise

pantxorama / Flickr

  • The park asks all visitors to abide by 14 rules, such as not feeding the wildlife, which can cause health problems or a dependence on human food, and remaining on marked trails to prevent erosion and vegetation disturbance.
  • Goods taken to the Galápagos must go through a quarantine process; for instance when crews on passenger planes, mid-flight, open overhead storage spaces and spray a pesticide to kill non-native insects. Before departing for our study site, we clean every bit of equipment, put the gear in sealed containers sprayed with insecticide, and leave it in a quarantine facility for 48 hours. Accidentally transferring an invasive species to an island could be devastating to the seabirds we study, and any number of other species.
  • Local businesses, Galápagos residents, and conservation organizations, like Galápagos Conservation Trust, are working hard to make the archipelago plastic pollution-free. Stores no longer offer plastic bags – you need a reusable one – and many restaurants are going straw-free. Recycling is mandatory and residents have been fined for failing to recycle appropriately.
  • Tourism creates huge economic benefits. Visitors to the Galápagos pay a mandatory $100 fee upon arrival, with the majority of the fee going to support the Galápagos National Park. Approximately 70% of the archipelago’s economy stems from tourism-related activities, and many of the 25,000 legal residents work in the industry as restaurant and hotel staff, taxi drivers, and national park guides.

taxing / Flickr

Potential Harms

  • Today, more than 200,000 tourists annually visit the Galápagosbringing the risks of new invasive species. More 866 non-native plant species have already been introduced across the archipelago. Most of these species sneak in accidentally – a seed stuck to a tourist’s sock or riding on a cargo ship might grow into a plant that can take over a landscape. Some were introduced as food crops, like the blackberry plant that now covers approximately 12% of the archipelago. Small insects and seeds can be difficult to prevent from entering the archipelago, even with the biosecurity measures. Organizations, like the Galápagos Conservancy, are helping to fund the development of effective control techniques for invasive species.
  • While the rules laid out by the park are good and very important, they can be difficult to enforce. One of the most innocent rules to break: respect the two-meter (six-feet) distance from the wildlife. Animals on the Galápagos Islands evolved with no predators, making them appear “tame” and easy to approach. It's natural, at first sight of a large Galápagos tortoise, to want to step closer. But animals can be sensitive to our presence in imperceptible ways, like increasing stress hormone levels or metabolic rate. Seabirds in the Galápagos, for instance, avoid nesting close to tourist trails. Respecting these rules is crucial and sometimes overlooked, depending on the guide and tour.

"Do I look tame to you?"

Tak / Flickr

Be a better tourist

I love travel, and exploring a country can change your life – it was a semester studying abroad that directly shaped my professional path. Given my experiences and the travel necessary for work, I'm in no position to call a halt to traveling, but I hope that we can be good travelers. Though tourism and global travel can have negative consequences on the environment, we can easily start to reduce these effects. 

  1. Research your destination ahead of time. Are sustainable tourism practices already in place?
  2. Consider choosing an environmentally friendly tour operator, or tour operators that give a portion of proceeds toward research or conservation. For example, Ecoventura, a tour operator in the Galápagos, will donate a portion of cabin sales to the Charles Darwin Foundation and Galápagos National Park.
  3. Reduce single-use plastic. Reusable water bottles and small reusable bags brought from home can help a lot. Avoid disposable plastic straws, which only get added to landfills, and check out alternatives that you can stick into a backpack easily.
  4. Eat at local restaurants and ask where the fresh fish or produce originates. Choose to eat at restaurants that serve seafood caught in-season, not illegally harvested.
  5. Shop at local stores, especially those selling products made from local artisans.
  6. Give careful thought to your souvenir purchases. Local shops in the Galápagos sell beautiful black lava and red coral jewelry – illegal when harvested from the Galápagos. When asked about the origin, the stores will say that they don’t come from the Galápagos; regardless of the origin, harvesting rare parts of nature is unsustainable.
  7. Be a considerate photographer. In the rush of the moment, it can be easy to forget where you are and try to get closer for a “more perfect” photo. Keep in mind that if you step off the path, you might cause an animal harm, damage small plants, cause erosion, or hurt yourself.
  8. If possible, give back to the area you visit. Conservation organizations gladly accept donations. Participate in the local conservation organization’s annual photo contest – it helps provide them with an endless number of promotional photographs.
  9. Consider staying more local. Explore a state or national park closer to home.

Since teleporting to destinations isn't yet an option, transportation-related tourism will continue to be a huge contributor to carbon emissions. But we can make some changes to what we do at our destination to be better tourists. If we keep in mind how our travels affect local communities, we can leave these natural areas in a beautiful state for generations to enjoy.

Jenny Howard studies



Wake Forest University


]]> Thu, 23 Aug 2018 18:35:16 EST It looks like microbes can help clean up mining pollution Experiments at an abandoned 4,000-year-old mine have researchers optimistic Rose Jones Staring down into the hollowed-out corpse of Parys Mountain, the rock walls are streaked in layers of vivid red, orange, yellow, and grey. Piles of rubble tower as far as the eye can see. Corrosive acid pools the color of dried blood drain into local streams. The abandoned mine has a poisonous legacy that stretches back 4,000 years – heavy metals have been extracted here since the early Bronze Age. Once the largest copper mine in the world, the site in North Wales stopped producing in the 1950s because it became cheaper to import copper ore from other countries. Abandoned for decades, it’s still one of the biggest heavy metal pollution sources in Britain.

This toxic landscape is the result of millennia of metal sulfide ore mining. The Parys ore deposit is an ancient hydrothermal vent field, layered with minerals containing a complex and rich metal content. Ores at Parys contain lead, zinc, and a whole host of other metals, in addition to the more usual iron, sulfur, and copper. When people dig into the ore in a mine, it's exposed to oxygen and water. This starts a cascade of chemical and microbiological interactions that releases and dissolves the metals into water, making it extremely acidic as it flows out into the surrounding streams, soil, and nearby coast. Metal pollution from the water leaves measurable traces in sediments, plants, and and local wildlife.

Carl Jones / Flickr

Obviously, acidic mine waste (usually referred to as acid mine drainage or AMD) like the contaminated water from Parys Mountain and other sites is a problem. There are an estimated 280,000 abandoned mine sites like Parys Mountain in the UK alone. The United Nations Development Council recognizes acid mine waste as a key concern, releasing their latest report calling for better mine waste management in 2017. However, cleaning up, or remediating, this type of pollution is not easy or cheap. Storing mining waste behind large dams was historically popular, but the catastrophic and tragic consequences that follow a dam failure, like the Brazilian Bento Rodrigues disaster in 2015, illustrate this strategy's shortcomings. 

Up until 2003, Parys Mountain waste was stored behind dams in big overground and underground acidic lakes, with water so toxic that locals used to dissolve cars in it to dispose of them. But the dam was declared unsafe, so the polluted lake was emptied into the nearby Irish Sea. This kind of disposal into seawater is widely used and relies on the assumption that dilution will solve the problem. There isn't much primary research on the topic so we can't say how true this is with confidence, but research suggests that dissolved metals persist in the local marine environment much longer than we previously understood and may find their way into the local food chain.

Duncan Stephen / Flickr

At Parys, the acidic mine waste water drains through a natural wetland system constructed in 2003, to reduce its acidity and provides a place for some of the metals in solution to fall out. This kind of treatment system isn’t a perfect solution though, as plenty of metals still end up in the Irish Sea. It also needs lots of nearby land, which isn't always available near abandoned mines.

I spent part of my doctorate thesis work in the field of Bioremediation, testing a different approach. My advisor and I designed a system that would cause a shift in the microbial community from the polluted water – essentially, encouraging particular microbes to grow that do things we find useful in this situation. This kind of biotechnology dates back as far as the Romans, who used it to treat their waste water though they didn’t really know why it worked. We also aren’t the first to think of applying biotechnology at Parys. 19th century miners used a primitive form of the same idea, extracting copper from the polluted waters by creating settling ponds where microbes caused copper to collect as a solid coating on scrap metal.

We had previously identified and officially named a species of acid mine waste microbe, Acidithrix ferrooxidans, from Parys Mountain that was new to science. This newly discovered species converts iron from dissolved to solid form – essentially the metal appears out of the polluted water as rusty chunks – and naturally grows as long, stringy anchored streamers in the toxic waterways draining the old mine. So we wondered: Could we grow enough of this species in the lab to help clean a stream of raw mine waste water from Parys Mountain? We hoped the microbe would remove dissolved iron and some of the other metals, while staying as anchored streamers in a big container, keeping the metals and microbes from being continuously being washed away.

Stephen McParlin / Flickr

To test our theory, we built two small-scale containers from odds and ends of plastic piping, junctions and fermenter bottles and grew a bunch of the Acidithrix ferrooxidans. We then fed the microbes a continuous stream of raw Parys Mountain corrosive mine waste, which we collected each week in plastic 20 L bottles from the polluted Afon Goch ('Red River' in Welsh, the native language) drainage stream and drove cautiously back to the lab on twisty rural one-lane roads so as not to jostle the big bottles and risk spilling drops of metal-eating water into the car.

Much to our delight, it worked. The system removed 90 percent of the iron from the contaminated water by the end of five weeks. Even better, wild microbes from the polluted water settled into our container as well, helping the system to work better.

But, as with all science, there are hurdles in scaling the concept up to work on site at Parys Mountain. For example, the microbes don't strain out all of the dissolved metals found in Parys water so we need to find a way to handle other metals before we have a full mine waste pollution treatment system. This kind of biotechnology is slower to develop than conventional technologies, because you have to make sure microbes can cope with the conditions you give them. But in return, you get a self-sustaining bioremediation system that – if you design it right – needs fewer additions, is cheaper, and demands less from the environment than conventional methods. The biggest source of acid mine waste pollution in the UK, Wheal Jane tin mine in Cornwall, has a pilot plant scale example of this kind of combination microbial bioremediation tank and wetland system.

At Parys, it’s very unlikely that the mine site itself will ever recover fully – but treating the polluted water is important to stop it further poisoning the land around it. Nor is this just a problem for Parys Mountain or North Wales. Wherever there is mining, there will be mine waste that needs treating. Modern legislation generally requires new mines to plan for dealing with the waste, but many abandoned mines are left that need attending to. This could be one potential solution.

Rose Jones studies

Environmental Microbiology


Bigelow Laboratory of Ocean Science














Protectors at Puʻuhonua o Hōnaunau National Historical Park

Wikimedia Commons





Patty Hamrick studies



New York University




That bulbous nose: irresistible

Wikimedia Commons



















Julie Hollis studies



Government of Greenland


]]> Tue, 29 May 2018 09:05:37 EST Trump's wall would harm unique and fragile wildlife on the California border Plans must include environmental impact studies Christa Trexler Currently, the United States and Mexico are separated at the San Diego County line by two to three layers of border fences with an access road between them. The primary fence was built in the 1990s and a permanently lit, secondary fence, built in 2008. Neither of these projects included environmental impact studies before, during, or after they were completed. Scientists who conduct research in the area say that the construction impacted many rare plants and animals, including all but one of the area’s Shaw's Agave plants, which grow here and only one other place in the country. Researchers were able to relocate several rare plant species, but only with limited success; the plants were not reintroduced to their original location, and the likelihood of repeat disturbance along the border is high.

Now, as these borderlands are just beginning to heal, we are bracing for construction of a new barrier. This new border wall will replace the fences; prototype designs suggest that it will be solid, and much deeper underground than the current structures, stopping any remaining natural movement of seeds, pollen, insects, and a plethora of small animals such as lizards, snakes, mice and other mammals through the fence.

Shaw's Agave

John Rusk / Flickr

In addition to human rights and civil liberties obstructions, this solid barrier will artificially fracture the area's plant and animal populations, home to the greatest biodiversity in the nation. Hundreds of these species are rare, and dozens are threatened or endangered.

The state of California and environmental groups have been fighting hard against the Trump administration’s complete disregard of dozens of environmental laws while rushing to begin the border wall project. Unfortunately, US District Court Judge Gonzalo Curiel recently ruled that the Trump Administration did not abuse its power by waiving environmental laws during the rush to start the border wall project in San Diego County. This decision has allowed the project to continue despite scientific experts pleading for environmental protections and warning of dangers to come. As construction proceeds, it's vital to include environmental protections for this unique ecosystem.

duncan c / Flickr

This physical barrier will not only negatively impact this one-of-a-kind environment, but also the scientific research occurring on both sides of the wall. This research is critical for protecting the rare plants, wildlife, and waterways which have otherwise been forgotten. Cross-border scientists already experience difficulties accessing their research areas, transporting critical specimens, communicating with each other, and interacting with border patrol agents. These hurdles end up not only affecting these researchers' science, but also their safety: several researchers have told me that they have frequently been made to feel like criminals by US Customs and Border Protection when they were only doing their jobs. What chance does this ecosystem have if the only people protecting it are kept out, penalized, or ignored?

Backbone Campaign / Flickr

Maintaining relationships across the border is not only critical for scientists, but for our entire community. The lack of communication and environmental concern has created a sewage-pollution crisis at the Tijuana River estuary region, causing not only uninhabitable areas for wildlife but also many San Diego beach closings. The many threatened species require binational conservation plans and combined efforts to ensure their long-term survival. These are complex problems, and we need Mexico’s help to fix them. A fractured relationship across our border benefits no one and continues to hinder the scientific progress desperately needed for solving the border region’s pressing environmental and civil needs.

We need to push our representatives to support California Attorney General Xavier Becerra’s appeal to reverse Judge Curiel's recent decision. And if the project is allowed to continue, we must demand that environmental impact studies be performed. In the future, there are many conservation actions (like preserving seeds from critical populations) that can be implemented. But right now, nothing is being considered except the construction of an impractical wall, which will harm current and future biodiversity around it: as this region warms with the changing climate, this wall would likely prevent adaptive movement of plants and animals northward. As scientists and allies, we must use our voices to communicate to our representatives the profound damage this border wall will have on the environment, our community, and scientific progress.

Christa Trexler studies



UC San Diego


]]> Wed, 16 May 2018 16:30:45 EST Coal ash contains lead, arsenic, and mercury – and it's mostly unregulated Can science find solutions where policy lags before the damage deepens? Laura Mast In 1989, the Exxon Valdez oil spill made headlines when the tanker ran aground off the coast of Alaska, spilling 10.8 million gallons of crude oil over several days. It’s since been eclipsed by the Deepwater Horizon oil spill into the Gulf of Mexico. But even that pales in comparison to the Kingston Fossil Plant coal fly ash slurry spill in 2008.

Around 1 am on December 22, 2008, a containment wall broke at a coal-fired power plant outside Kingston, TN, and 1.1 billion gallons of coal ash spilled over into an adjacent river and the surrounding land. That's the equivalent of 1,660 Olympic-sized swimming pools of toxic waste. The ash slurry was over six feet deep, covering around 300 acres. Though you might not have heard of it, it was 100 times the size of the Exxon Valdez spill.

Coal itself isn’t a particularly toxic material. But after it's burned, what remains in the ash includes lead, mercury, cadmium, chromium, arsenic, and selenium, all in levels that may threaten human health. It's not a problem that's limited to Tennessee: coal combustion has been a significant source of power in the US since the early 1900s, so over a century of coal ash has built up. The most recent data on ash stockpiles come from 2014; in that year alone, the US produced 130 million tons of coal ash. To put that in perspective, that's about a little under half the weight of the entire human population on Earth.

Some of this can be beneficially reused – instead of putting it in a landfill or just storing it near power plants, we can use it in concrete or as filler in things like roads and embankments. Using ash in concrete, for example, locks in the heavy metals and makes the concrete stronger. The fact that it can be used productively, though, is what has held the Environmental Protection Agency (EPA) back from labeling it as a hazardous waste.

The Kingston Fossil Plant coal fly ash slurry spill

US Tennessee Valley Authority

A hazardous waste label puts the federal government in charge of how a material is handled. Industry members argue that a hazardous waste label would make coal ash more difficult to recycle, ensuring that it remains stored in landfills. But right now, and for the foreseeable future, states are allowed to dispose of coal ash as they see fit, which has led to spills and seepage into groundwater.

There are over 1,000 active coal ash storage sites across the United States, and to date, there are no legal requirements for container liners or leak detection systems. Often, catastrophic containment failures – like the Kingston spill and the Dan River spill in Eden, NC, just a few years later – happen after a holding pond wall cracks or a major pipe breaks. But there's also danger from from unlined basins or otherwise improperly managed landfills, which can cause slow seeps of contamination, and are also sources of long-term illness and environmental damage.

In the early 2000s, according to a 2007 EPA report, coal ash leaks contaminated groundwater with heavy metals in 67 towns across 26 states. But that number is likely under-reported: Often, utilities that own the coal ash storage sites aren’t required to monitor their groundwater. Because monitoring isn't required, it's hard to know how big this problem really is.

Coal ash in the water

Overall, this seems like a situation that calls for a clear solution: regulation. The EPA came close to regulating coal fly ash for decades, but always pulled back due to industry pressure. But in December 2014, the EPA finally addressed coal ash's hazards of in a landmark piece of legislation called the Coal Combustion Residuals (CCR) Rule.

The rule established location and design requirements for storage facilities. Coal ash ponds, for example, were forbidden above uppermost aquifer layers, or near wetlands, or seismic zones. Under the rule, existing ponds needed to have composite liners and monitor groundwater conditions, and new ponds needed to have water collection and removal systems. There were a host of other structural and safety assessments with annual or weekly requirements introduced, too.

These regulations were expensive but straightforward, and designed to protect the public by protecting groundwater from contamination. Most environmental advocacy groups said the rule didn't go far enough; as a National Science Foundation Fellow in Environmental Engineering at Georgia Tech, I was interested to see what the industry members themselves would think.

USFWS responders


I soon got my chance: in the summer of 2016, I attended a meeting of utility executives. The mood around the regulation was begrudgingly accepting – “All right, here we are, let’s make the best of it.” In fact, most of the utility folks I spoke with seemed grateful to have the regulation. 

"The regulatory uncertainty that has impeded the beneficial use of coal ash for half a decade has finally come to an end," said Thomas H. Adams, the executive director of the American Coal Ash Association, in a 2014 statement made shortly after the EPA published the standards.

As an environmentalist, reuse and recycling are generally music to my ears. (And coal fly ash reuse is no joke – for every ton of ash used instead of traditional cement, we prevent a ton of carbon dioxide from entering the atmosphere). But of course, reusing coal ash is not always possible – or even beneficial. After a golf course in Chesapeake, VA, used 1.5 million tons of coal fly ash as filler, it was found responsible for high levels of lead and arsenic in the groundwater below just two years later. Similarly, when a playground in Pines, IN, used coal fly ash as filler, the extent of the groundwater contamination was so severe the EPA designated it a Superfund site in 2012. So there's an ongoing question: How can we make this kind of recycling actually safe?

Seepage in 1963 from a coal ash pond on Cape Fear

Waterkeeper Alliance Inc. / Flickr

At the time, it seemed like this regulation would be a step toward answering that question. As a scientist, it appeared to be a win-win: It would help companies feel secure investing in research on reusing coal ash. And it would help researchers keep learning safe ways to reuse the ash, while protecting communities where it was stored in the meantime. But all of that was before Trump was elected.

Under Trump's EPA Administrator, Scott Pruitt, there's been a massive redirection of the agency's policy, from its approach on climate change to more common-sense regulations on pollution. Pruitt has rolled back regulations on the Clean Water Rule, the Clean Power Plan, car emissions standards – and, unfortunately, on coal ash.

In March 2018, the EPA proposed more than a dozen changes weakening the Coal Combustion Residuals rule. States may decide to use "alternative standards" for contaminants, as well as decide when and whether groundwater monitoring would be required, as well as what remediation actions, if any, should be taken. 

“Today’s coal ash proposal embodies EPA’s commitment to our state partners," Pruitt said in an official EPA press release, "by providing them with the ability to incorporate flexibilities … based on the needs of their states.” The potential health consequences of the rollback were not discussed, but the EPA did note this amendment will save the utility sector between $32 million and $100 million in annual compliance costs.

Scott Pruitt

Gage Skidmore / Flickr

The key to making coal fly ash safe to recycle is finding a way to lock in its toxic elements. Products that transform the coal fly ash, like concrete, do this really well; the heavy metals get "encapsulated" into the concrete matrix. Even if you pulverized the concrete, the heavy metals wouldn't be accessible. Without encapsulation, like when coal fly ash is used as filler, these toxins stay loose and can leach into water.

Concrete made of coal fly ash is stronger, less permeable, and requires less water. But it's hard to work with because the composition of the ash is highly variable – imagine trying to make a cookie recipe, but when you go to buy flour, it's different every time! My lab at Georgia Tech is studying this dilemma now, experimenting with new ways to lock in the toxins.

But while we pursue scientific answers, coal ash is facing a fundamental political challenge, too. The roll-backs on the CCR role have once again placed the waste into the realm of regulatory uncertainty. What is clear, though, is that the health of communities and the environment depend on us figuring it out.

Laura Mast studies

Environmental Engineering


Georgia Institute of Technology


]]> Mon, 14 May 2018 16:02:34 EST Tracking the history – and future – of the world's largest penguin breeding colony Climate change is upending migration patterns that predate Cleopatra Brittney Borowiec Dressed in their best tuxedos and a distinctive ring of white eyeliner, Adélie penguins return to Cape Adare, Antarctica, every breeding season – October to February – to raise a family after spending the winter foraging at the edge of the fast ice growing out from the shore. Pairs often reuse their rock pile nest from previous seasons, and travel thousands of miles to return to the exact same spot every year. A few quick renovations, like building up walls knocked over by gusts of wind, and replacing pebbles pickpocketed by neighbors, and they’re ready to go. The colonies are noisy, and prime real estate near the water is at a premium with hundreds of thousands of breeding pairs staking claims.

The best sites are on Ridley Beach, a 0.31 square mile section of Cape Adare that juts out into the Southern Ocean. It’s covered in smooth, black pebbles, sculpted into ridges by the relentless, heavy surf. Pools of standing seawater break up the landscape, trapped ashore by storm surges and heavy winds. During breeding season, it’s hard to tell exactly what the ground looks like at Ridley Beach because every inch of it is covered by penguins.

There used to be even more of them, reports Steven Emslie, a marine ornithologist based at the University of North Carolina. His survey of active and abandoned penguin settlements on Cape Adare, recently published in Royal Society Open Science, details the rise and fall of the world’s largest Adélie penguin colony over the last 2,000 years. It’s the end result of two field expeditions, in January 2005 and 2016, to the bottom of the world.

The Adélie penguin empire in the Ross Sea is dynamic, and has rolled with the punches of shifts in sea ice and climate change for millennia. Knowing the details of this natural history is a useful tool for predicting how populations may fare in an uncertain future, as warming temperatures and rising sea levels steal access to proven breeding sites.

Picking their way between nests, chicks, and cranky parents, interloper scientists searched for clues to reconstruct the natural history of penguins in Antarctica. Like bygone human civilizations, information about ancient penguin settlements here is written in what’s been left behind – old feathers, bones, and eggshells. Armed with a handheld GPS, a trowel, and a tarp, the researchers systematically excavated old, unused pebble mounds, looking for buried treasure to bring back to the lab for analysis.

Wikimedia Commons

Back in the lab, radiocarbon dating analysis aged each of their samples. By comparing the amount of carbon-14, which decays over time at a known rate, with the amount of stable carbon-12 in a sample, researchers can precisely estimate the age of a material.

They found that penguins have been on Cape Adare for a very long time. While Cleopatra and Julius Caesar were fighting civil wars, Adélie penguins were waging a campaign of their own far to the south. Driven out of colonies along the Scott Coast by encroaching ice cover during a cooling period in Antarctic history, they scoured the coast for polynyas, areas of open water surrounded by sea ice, that make perfect nurseries. Adélie penguins need reliable access to the sea to forage for food, and spend the vast majority of their lives by the water. Large-scale changes in ice formation forced them to find new, warmer breeding sites. The first penguin pioneers arrived at Ridley Beach about 50 CE, roughly 150 generations removed from its current inhabitants.

Bolstered by huge swarms of krill and ocean upwelling, the colony ballooned in size over the next 800 years. Penguins occupied not only the entire Ridley Beach, but most of the upper terrace overlooking it, a lengthy, treacherous walk from the sea. Even penguins will suffer a rough commute if it means they can have a nice, safe place to raise their children. At its height, this penguin boomtown was a supercolony composed of over 500,000 breeding pairs.

But few penguins live on the steep slopes of the terrace anymore. Sometime after the eighth century, the colony mysteriously collapsed to its present size of about 340,000 breeding pairs. Perhaps the wind patterns changed, or the air temperature cooled, or the stretch of open water near the beach shrunk in size. Similar events have caused total breeding failure, lower chick numbers, and increased mortality in other colonies along the Ross Sea. Antarctica is an unpredictable land of extremes, and it’s anybody’s guess what actually happened.

Ridley Beach remains fully occupied today, but is increasingly swamped by storm surges and waves whipped up by high winds. Melting glaciers and climate changes are causing the sea level rise quickly in the area, drowning out more and more waterfront nest property every year. In the near future, the low-laying areas occupied by colony will be in danger of submersion, making the beach uninhabitable.

Where will the penguins go? We can look at their history for answers. Cape Adare penguins will probably retreat to the higher ground of the upper terrace, as they did before when the beach was too crowded. But not all colonies along the Ross Sea have penguin-friendly slopes near the shore, and the effects of climate change will soon displace hundreds of thousands of penguins from their historic breeding grounds. Like their ancestors 2,000 years ago, they’ll have to set off into unknown waters and establish colonies elsewhere. Maybe they’ll be able take up residence in old breeding sites once cut off by ice formation, but now accessible due to glacial melting and ice breakout. Perhaps they’ll go elsewhere.

With the breakneck speed of climate change, accelerated by human activities, it’s unclear if these waddling, curious, and obstinate birds will be able to adapt.

Brittney Borowiec studies

Comparative Physiology


McMaster University


]]> Tue, 08 May 2018 16:27:23 EST Tree-murdering fungi and insects increasingly contribute to climate change New research suggests carbon dioxide released from dying forests equals emissions from 11 million cars Ellen Stuart-Haëntjens Forests have existed many millennia longer than humans. To be more precise, trees have 380 million years on our 200,000. (That's when modern humans evolved. If you start counting when our lineage split with chimpanzees and gorillas, humans have only been around for about 6 million years.) Forests have long been an important resource, and not only in human development — even today, they account for 80 to 90 percent of land-dwelling biodiversity. These crucial ecosystems filter water, harbor wildlife, and absorb carbon dioxide, helping mitigate climate change.

But forests are currently threatened by deforestation, rising global temperatures, increasing extreme weather events, and intensifying pathogenic outbreaks — caused by widening pest ranges and invasive species. The global impact of this forest die-off is extreme: Carbon that accumulates year after year in living trees escapes from dead and decomposing trees back into the atmosphere.

Because there are so many factors leading to forest loss, it's been difficult to compare the extent of the different destructive factors or create effective management strategies. Clear-cuts and raging wildfires tend to be blamed, and do certainly release massive quantities of carbon. But a new study, published in Global Change Biology, found that a more subtle set of disturbances may actually be doing US forests just as much damage.

Death by chomping

Scientific interest in the carbon released by insects and tree-strangling pathogens (such as fungi) has recently spiked, perhaps spurred by the growing visibility of forest loss. The first comprehensive large-scale study was published in early 2018 by Markus Kautz, a forest ecologist at the Forest Research Institute Baden-Württemberg, and his collaborators. Stunningly, they found that in the United States between 1997 and 2015, insects and pathogenic infections resulted in at least as much carbon release as forest fires.

The impacts of pest disturbances on forest carbon cycles had been examined before, but only on fine spatial scales, such as a single forest stand or landscape. One reason this research had been limited is that ecological field data is constrained by time and man-power – imagine how long it would take to sample every tree in every forest every year. Modelling insect and pathogenic disturbances is also incredibly complex. Unlike other common disturbances like fires, storm blow-downs, or clear-cuts, insects and pathogens inflict very diverse types of impacts, making it harder to estimate their cumulative effect.

Forest with pine beetle damage

U.S.D.A. / Flickr

To solve this challenge, Kautz and his team combined remote sensing technology using zoomed-in images captured by satellites in space. Piece by piece, the scientists stitched together 19 years’ worth of aerial images and associated pest-induced disturbances taken via airplane. (Thank you, USDA Insect and Disease Survey.) Then they mapped satellite vegetation cover data on the images in order to separate forests from other vegetation. Finally, they put everything into a computational model containing climate data and known carbon cycling dynamics. To confirm the accuracy of their results, they compared the model to actual data collected in the field — comparing 40 percent of the study area for nine of the 19 years. The computer generated values were eye-poppingly close.

Of the insects and fungal pathogens included in the study, bark beetles negatively impacted forest carbon stores the most. These bugs account for 61 percent of the total tree loss over the 19 years, far exceeding damages from other common plagues like sudden oak death pathogens or gypsy moths. Most of the bark beetle havoc is concentrated in western, coniferous forests, but the pest is also increasingly found in pine populations throughout the eastern US. As the climate warms, the beetle's habitat is expanding, which will likely lead to more dead trees.

Dendroctonus micans

Gilles San Martin / Flickr

In previous field studies, scientists developed a good understanding of how environmental variables, like temperature and precipitation, change the way trees grow – which in turn impacts carbon sequestration. Environmental data from individual locations can therefore be used to predict tree growth, and therefore the amount of carbon storage. The same is true of tree death and carbon release: equations describing tree mortality data can be added to the model. For instance, if location X receives less than 50 percent average rainfall for six months, Y number of trees will die. Or, if a fire burning at A degrees for B number of hours rages across C number of acres, D number of trees will die.

To put it simply, scientists use real data collected in the field to inform computer simulations that then generate educated estimates. Adding aerial images, the way Kautz did, improves the previous estimates' accuracy.

Calculating CO2

Forests are critically important for climate-change mitigation, absorbing about 925 megatons of carbon dioxide in the US alone. That's equivalent to 14 percent of the country's yearly greenhouse gas emissions. But thanks to insect disturbances, those numbers may be changing: Kautz's study suggests tree-killing pests are responsible for emitting as much carbon dioxide as an additional 11 million vehicles. (If you're interested in learning more about how various emissions compare, you can calculate equivalencies using the EPA Greenhouse Gas Equivalencies Calculator.)

Let us end on a couple of hopeful caveats. First, insect and pathogenic disturbances rarely kill every tree in a forest stand, instead resulting in unevenly distributed mortality. And, dead wood decomposes slowly, generally over several years. This gives the surviving trees a chance to re-absorb some of their neighbors' carbon dioxide, potentially capturing the greenhouse gas before it has a chance to reach the atmosphere and contribute to global warming.

Pine beetle forest death

NASA Goddard Space Flight Center / Flickr

Additionally, in some cases, low to moderate disturbances — pests or diseases that kill off a scattering of trees – can actually improve the overall growth and carbon storage capabilities of a forest. In a Michigan forest field study, for example, when 38 percent of trees died in the span of three years, the increased light and nitrogen resources actually allowed the surviving trees to increase their growth. Strangely, the tree loss ended up leading to a net gain in the rate of carbon storage. Of course, these built-in recovery mechanisms have their limits. If too many trees die, there may not be enough remaining vegetation to pick up the slack. Within that same Michigan forest, in areas where more than 60 percent of the vegetation perished, forest growth declined precipitously.

This distinction highlights the importance of accurately modelling the impacts of past disturbances. Continental scale studies, like the one by Kautz and his colleagues, provide detailed data for decisions such as where to invest resources to protect forestland or to grow timber plantations. And as forest disturbances continue to increase in frequency, intensity, and extent, identifying such regions is more vital than ever.

These research methods should now be applied at a global scale to see how pest-induced disturbances affect each continent and forest type. Further improvements can be made by taking more detailed, fine-scale remote-sensing satellite images — which NASA is planning! — as well as gathering ecological field data from more neglected forest regions around the globe. 

Additional research should explore how coupled disturbances, like a simultaneous drought and insect outbreak, can compound forest carbon loss. With the livelihoods of billions of people, a multitude of flora and fauna species, and the global climate at stake, we owe it to the future to try to predict how forests can be better managed for resilience in this changing world.

Ellen Stuart-Haëntjens studies

Ecology and Biogeochemistry


Virginia Commonwealth University


]]> Tue, 01 May 2018 16:19:49 EST How atmospheric dust might help cool the planet New research suggests an old idea of geoengineering has more merit than long suspected Elisa Bonnin As the earth continues to warm, it is becoming increasingly clear that we cannot ignore the possibilities of geoengineering, the branch of science that develops techniques to artificially cool the planet. Indeed, it may soon become necessary to take drastic action to prevent the worst effects of climate change. However, that doesn't mean that geoengineering experiments should be undertaken without caution and care, because the underlying impact of those experiments could very well end up causing more harm than help.

Iron fertilization as a geoengineering method was mostly considered in the late 1990s to early 2000s, and as an idea, it came about because of a very fundamental oceanographic question: why do certain areas of the ocean have very low amounts of plankton, even when they have enough nutrients for those plankton to grow?

In most areas of the ocean, phytoplankton, the tiny plant-like creatures that produce most of the oxygen in the ocean (and about half of the oxygen on the planet), need only two things to grow: light and nutrients. But there are some areas of the ocean that contain high levels of nutrients and no phytoplankton, even during times of the year when light conditions are right. These regions, called high-nutrient, low-chlorophyll regions, puzzled oceanographers until 1990, when a scientist named John Martin proposed that iron might be the missing link.

The limits of iron 

Iron is a micronutrient – living things don't need a lot of it, but what they do need, they can’t do without. Places like the Southern Ocean, off the coast of Antarctica, have almost no iron at all. This is because iron is a terrestrial micronutrient, meaning it comes from the land. The most common sources of iron to the ocean are rivers and wind-blown dust from deserts. Antarctica, covered in ice and isolated from other continents, has none of that. Martin proposed that that was why the phytoplankton weren’t growing. To prove it, scientists went out and conducted iron fertilization experiments by artificially adding iron to the ocean and see if the phytoplankton grew. Within a day of adding dissolved iron into the ocean, scientists observed a phytoplankton bloom.

Hungry for iron

Picturepest / Flickr

That research was interesting and exciting, but the most exciting part for some people was an interesting link between phytoplankton and carbon dioxide. See, just like plants on land, phytoplankton are photosynthesizers. They use up carbon dioxide to create oxygen, and with so much open, iron-limited space in the Southern Ocean, oceanographic researchers across multiple institutions worldwide started to wonder if, with just enough iron, we could stop climate change completely.

It didn't work out quite that nicely. Artificial iron fertilization was proven to be ineffective at removing carbon from the atmosphere. And over concerns, published in a letter to Science in 2008, that continuing to conduct these studies might harm the natural environment by allowing invasive species to grow or by altering the ecosystem in ways they couldn't predict, the research was effectively halted. (Some continued under the table. In 2012, a US-based entrepreneur named Russ George defied an ocean-dumping moratorium, convincing the Haida Nation to conduct an iron fertilization project off the coast of British Columbia, Canada, to boost salmon populations, with the idea that salmon would feed off of the resulting phytoplankton bloom. According to Nature, scientists have seen no evidence that the scheme worked.)

Cassie Matias / Unsplash

Since 2008, there have been almost no papers talking about iron in the Southern Ocean affecting the climate. However, new research by Gary Shaffer, a researcher at the University of Magallanes in Punta Arenas, Chile, and Fabrice Lambert, an assistant professor at the Pontifical Catholic University of Chile, suggests that the question of iron isn't fully closed. Their research, which is focused on atmospheric dust, a major source of oceanic iron, suggests that dust, and the iron in it, may have contributed to the onset of the ice ages. And understanding how the Earth has naturally cooled in the past, prior to human intervention, would allow us to better understand how Earth might cool in the future.

Simulating sun and iron

Ice ages are actually regular events. Over the past 800,000 years, we've had eight. To a certain extent, they can be explained by variations in Earth's orbit. However, one curious thing about the past few ice ages is that our records show a decrease of carbon dioxide during them, contributing to global cooling via reflection, where dust particles in the atmosphere reflect incoming sunlight back out into space, and iron fertilization.

And while Antarctica is usually far away from any sources of dust, Shaffer and Lambert's research, which combines records taken from dust measurements in ice cores over the past 300,000 years with temperature measurements calculated from those same ice cores in Greenland and Antarctica, shows that the amount of dust in the atmosphere increased greatly just before the start of the last three ice ages.

Clouds, not dust, over Antarctica

Yuriy Rzhemovskiy / Unsplash

While they state that this effect is not strong enough to cause an ice age on its own, the correlation is compelling, and Shaffer and Lambert make a convincing case that dust in the atmosphere might have provided the final push into an ice age. Using computer model simulations, they tested both the effect of reflection of sunlight and iron fertilization, and both appeared significant. Their research suggests that iron fertilization may play a part in cooling the earth after all.

However, that still doesn't mean that iron fertilization is the solution to climate change. Shaffer and Lambert's work showed that iron can contribute to an ice age that's already in development, not that it can start an ice age from scratch. The potential risks of artificial iron fertilization still need to be examined carefully before reopening the idea of using it for geoengineering so that we can fully understand the effects that this technique has on the natural environment and be prepared for any consequences that might result.

Elisa Bonnin studies



University of Washington


]]> Wed, 18 Apr 2018 16:29:48 EST 'Being Ecological' is a book with admirable aims and a tangled execution Prioritizing data over action can be counterproductive – but so is a muddled message Cassie Freund Ecology books are sometimes just a disheartening litany of what Timothy Morton, an English professor at Rice University, calls "factoids" – facts packaged into easily digested pieces of information – splashed against a backdrop of nature imagery and adventure stories. With his new book, Being Ecological, Morton makes an admirable effort to expand the genre into something more appealing to a wide variety of readers. However, the book lacks a clear take-home message, preventing Morton from fulfilling his promise to give the reader a greater understanding of what it really means to be ecological.

Morton's distaste for factoids appears to be rooted in the idea that scientists and writers use them to manipulate the audience's feelings, telling them what to think through a manipulative framing instead of allowing them to come to their own conclusion.

MIT Press

I disagree. I see factoids (I prefer to just call them "facts") as a way to distill complex ideas into easily understandable content and make scientific concepts more accessible to everyone. Yes, the simple act of even choosing which facts to include in a piece is inherently biased, but they do allow people to understand information that may be otherwise inaccessible. Part of me wondered if Morton's detailed and emphatic explanation of his opposition to factoids was his own way of controlling his audience and priming us to buy into his philosophical approach.

Still, as an ecologist and conservation biologist, I struggle with the question of how to motivate people to be more environmentally friendly, and I agree that overwhelming people with depressing facts is generally not the best way to persuade them. So I was initially intrigued and eager to read about the environment through Morton's point of view. After all, he makes an astute point that prioritizing data over action can be counterproductive: if only we had that one perfect fact, we think, then we would know how to solve climate change (or deforestation, or overfishing, or any other major ecological issue), so we continue to endlessly gather information instead of taking action to stem the consequences of environmental destruction. This phenomenon is often referred to as "analysis paralysis."

On the contrary, Morton argues that we don't need to learn any more about ecology to be ecological – we already are ecological, just by living in the world. That is, we are all natural beings that cannot live without the natural world, and this should be enough to push us to live more sustainably. If we are to escape the environmental catastrophe (Morton's words) that we currently find ourselves in, we must internalize the fact that our survival is inextricably tied to the planet's health.

But Morton fails to really drive this key main point home to the reader. Instead, he gets lost in long philosophical expositions that are only tangentially connected to ecological issues. He fails to tie ideas together, which forces the reader to work hard to understand his worldview. And for all of the emphasis at the beginning of the book about how urgently we need to take action – any action – to begin to extricate humankind from the ecological messes we have created, I turned the final page without any idea of what I should do. Nor, despite Morton's assurances that I "am already a symbiotic being entangled with other symbiotic beings," did I feel more ecological.

  Jason Blackeye / Unsplash

I see what Morton's goal was in writing Being Ecological. Humankind currently faces a daunting list of ecological problems: rising temperatures, shortages of fresh water, species loss. I agree with him that our neglect and flat-out abuse of our environment is rooted in the fact that we see ourselves as somehow separate from nature. We wear technology as armor to protect ourselves from things like predators, viruses, and famine that would kill us otherwise. Yet, we must still breathe oxygen, drink clean water, and coexist with the bacteria and microbes that enable life on Earth.

This is Morton's point: our basic needs and the fact that we are biological beings tie us to nature. Knowing this should make us more willing, motivated, and empowered to address environmental issues. I would have liked to see him spend more time building up these ideas and the philosophy behind them to make the reader not only understand his point, but to feel it in their guts and bones by the time they closed the book. But in the end, I just felt a bit confused, still unsure of how to translate the myriad of philosophical principles that Morton touched on into a more ecological worldview.

Although this book was not the inspiring guide to ecological thinking that I wanted, I did find some useful nuggets in the text. I particularly appreciated Morton's contention that, even with the most vigorous scientific effort, we can never know anything for certain. Our interpretation of the world is fundamentally flawed, "entangled with prefabricated concepts about what interpretation means." While this might be a terrifying concept for some, I find it strangely freeing.

Instead of anxiously trying to troubleshoot all of the hypothetical ill-effects of proposed environmental action or policies – a futile effort in our complex and dynamic world – Morton gives us permission to embrace the uncertainty. We must act now to mitigate climate change and biodiversity loss based on the information we have, and deal with potential stumbling blocks as they arise, he argues, instead of being frozen in place, just waiting for the right piece of data to tell us what do.

In other words, it's OK to act in good faith, based on sound science, and to do the wrong thing. It's just not OK to do nothing.

Cassie Freund studies



Wake Forest University


]]> Wed, 11 Apr 2018 16:10:17 EST How farmers on the Great Plains are changing the local climate New crop practices trap more carbon in the soil, increasing rainfall and adding profits Ellen Stuart-Haëntjens For the past century, the world's climate has rapidly warmed, spurred by a precipitous increase in the concentration of greenhouse gases that trap the sun’s heat in the atmosphere, preventing it from rebounding into space. However, around 30 years ago, one region in North America began bucking the trend. A decline in the agricultural practice of summer fallow – leaving wheat fields devoid of growth for a year between crop harvests – coincided with cooler springs and summers than those experienced by much of the rest of the planet, and with increasing rainfall in the northern Great Plains.

It turns out that rather than leaving fields bare, planting fields with shallow-rooted crops, such as corn and teff, in between wheat harvests has myriad advantages. The direct benefits include more economic success for farmers due to increased crop harvests, as well as improved soil health thanks to the stabilized, nutrient-rich topsoil, which would otherwise be eroded by the wind – think Dust Bowl. But the indirect benefits are even cooler (pun intended). The increased crop-cover absorbs, rather than releases, carbon dioxide (a greenhouse gas); it cools the region in late spring; and it increases atmospheric moisture. This additional moisture leads to higher rainfall during crucial months of the growing season. To put it simply, farmers altered their land use to increase income, which caused a change in local climate that counteracted the human-caused warming trend.

A farm in the Dust Bowl

US Department of Agriculture

The traditional belief – one that still prevails in some regions – was that leaving fields fallow for alternating growing seasons conserved soil water and nitrogen necessary for plant growth, and also broke agricultural pest cycles. Additionally, tilling the land, or turning the soil, during fallow periods controlled weeds and allowed soils to "breathe." The conventional wisdom went something like this: rigorous planting and harvesting exhausts the Earth, and the soil needs to rest. And without plants to feast on, fewer pests survive to attack crops next year. 

Then, about five decades ago, research began to reveal the negative consequences of summer fallow. We now know that summer fallow fails to conserve soil moisture in most places, because the water simply evaporates from the bare soil and into the atmosphere. Fallow also depletes soil carbon and nutrients, and increases the salt concentration in soil. Taken together, this makes land less productive in the long term. 

To minimally disturb soil during planting, most farmers in the Great Plains now use crop-rotation techniques combined with a practice known as direct seeding. Alternating different crops on the same farmland, while also maintaining soil's structural integrity, conserves soil nutrients and moisture, while also keeping weeds, fungal pathogens, and crop-munching insects at bay.

Aerial view of summer fallow in North Dakota


The conversion from traditional fallow to more sustainable techniques was slow to start, stunted by a technological lag and social resistance born of the cultural value farming communities placed on tilling the land. But many factors eventually brought about massive change in land use across the Great Plains: increased scientific research, the economic incentive of crop yields, advances in technology, local outreach events, farmer-to-farmer communication, and farmer-scientist collaborations. Since 1970, the regional area under fallow has gradually declined from 77 million to 20 million acres, with most of this decline between 1985 and the early 2000s.

Climate control

Scientists' curiosity about what land use was doing to the local climate did not stop there. Environmental scientists Tobias Gerken and Paul Stoy, and PhD student Gabriel Bromley, all from Montana State University, recently published a paper in the Journal of Hydrometeorology that linked the increase in summer planting to a heightened probability of a certain type of rainfall, called convective precipitation, that forms when thermal energy lifts moisture to a cold part of the atmosphere.

Importantly, raindrops do not all originate the same way. Frontal precipitation, also called cyclonic, occurs when cold air meets warm air and the dense cold air slides beneath the warm air, forcing it to rise. Orographic precipitation forms when aggregated, warm, moist air meets mountains and is forced to rise over the ridges. For both orographic and frontal precipitation, the air cools as it rises in altitude, condensing the water vapor into liquid rain.

Ellen Stuart-Haëntjens, Tracey Saxby and Alexandra Fries

Convective precipitation occurs when there is sufficient energy to lift water vapor from the ground to the part of the atmosphere cold enough for it to condense into clouds. In the Great Plains, increased crop cover in late spring and early summer results in increased atmospheric moisture, because when plants need to cool down or obtain carbon dioxide for photosynthesis, water molecules escape in a process called evapotranspiration. With hundreds of miles of plants across the plains, their collective evapotranspiration increases the likelihood of rainfall by convective precipitation.

Agricultural scientists often visit farms and give presentations at local farm bureaus to help farmers see the broader changes they create. Farmers care about the health of the land beyond their own bottom lines. 

“They are interested to know what is happening locally and why," Stoy said. 

Working together, farmers and the scientists increasingly understand how crop practices can have multiple benefits for productivity, soil conservation, and regional climate. The conservation of carbon within the soil helps grow healthier crops and prevents carbon dioxide release into the atmosphere, where it would contribute to global warming. And increased growth means cooler and wetter growing seasons in a region where water is crucial, i.e. more profits for farmers harvesting more crops.

Matthew Smith / Unsplash

Some regions, such as areas of the Central Great Plains, still rely heavily on fallow. There, the climate is so dry that alternative farming techniques, such as crop sequencing, are not currently possible. This is a concern because, as Stoy said, “fallow makes convective precipitation less likely, and those rain storms, especially earlier in the growing season, help a farmer out.”

Managing Expectations

Regional land-use change is only responsible for part of local climate control. As the global climate changes, the delivery of cold and moist air from the Arctic, and warm and moist air from the Gulf of Mexico, may also change. Adding to this, extreme climatic events, such as droughts and floods, are increasing globally, even in the northern Great Plains. 

“Large droughts can be hugely devastating,” Gerken said. Now, the research team is working to improve the forecasting of rapid onset droughts (one of which plagued the region in 2017), “to help farmers better manage the risk.”

Amid such precipitous change, there is at least one certainty: as economics, policy, and social networks continue to influence the region, and as the global climate continues to change, strategies for improved land management and climate adaption are increasingly vital to managing our own future. Collaborative efforts between scientists and stakeholders, such as those ongoing in the northern Great Plains, are key.

Ellen Stuart-Haëntjens studies

Ecology and Biogeochemistry


Virginia Commonwealth University


]]> Mon, 19 Mar 2018 09:57:29 EST Tropical rainforests may be near a tipping point beyond our control Deforestation may work like diseases: uncontained, it can win Michael Graw The planet is losing an estimated 80,000 acres of tropical rainforest every day. And while that amount of deforestation – more than twice the area of Costa Rica each year – seems like it could result only from a colossal bulldozer plowing across an entire continent of forestland, the reality on the ground is anything but uniform.

In the Amazon, Congo, and Indonesia, the three regions that are home to nearly all of the world’s tropical rainforests, the human motivations behind and methods of deforestation are entirely distinct. In South America the most significant driver of forest loss is the need to clear land for industrial-scale agriculture and ranching, so huge swaths of forest are burned into oblivion by human-set wildfires. In Southeast Asia, on the other hand, the high price of timber in the global market makes clear-cutting a lucrative venture. In Africa, deforestation lacks this industrial scale, but is more haphazard as small farmers clear land in piecemeal efforts to plant subsistence crops.

The net result is that the rainforests of today’s post-industrial world are more like millions of tiny, isolated patches of forest than the massive stretches of jungle that blanketed the tropics for millennia. The ramifications echo far beyond sentimental conservation – these forest fragments collectively emit 31 percent more greenhouse gases to the atmosphere than intact rainforests, even after accounting for emissions from deforestation. In addition, numerous plants and animals that call the tropical rainforests home, and that inspire pharmaceuticals for human medicine, have struggled to adapt to patchwork forests, and so face extinction.

The Amazon

CIAT / Flickr

These forest patches in the Amazon, Congo, and Indonesia were created in different ways, so it seems inevitable that the complex forest mosaics left behind by deforestation are unique across the regions. Yet a new study, published in Nature last month, found that despite the differences in where, why, and how rainforests are destroyed, from a mathematical perspective the resulting mosaics look essentially the same. And, ominously, the math suggests that tropical rainforests may be nearing a tipping point beyond which deforestation will spiral out of human control.

The key to this warning is a mathematical concept called percolation theory. Percolation theory may not sound familiar – it lacks the fame of the Big Bang theory or evolution – but like gravity, it seems to apply ubiquitously in the natural world. At its simplest, the theory seeks to describe how structures that repeat themselves in nature, like ice crystals in near-freezing water, cliques in a social network, or clouds across the sky, behave when subjected to an outside change. The equations derived from percolation theory seem to fit nearly everywhere scientists look: they’ve been applied to phenomena as disparate as earthquakes, epidemics, and forest fires.


Club Med UK / Flickr

But there’s a common thread: all of these phenomena have a so-called critical point, a point beyond which behavior transforms from moving slowly and steadily to moving all at once. Take disease, for instance. When only a few people are sick, the infection can spread – but only slowly, a few people at a time. However, percolation theory states that once the number of people infected surpasses the critical point, the disease is almost certain to rapidly infect the rest of the population. In the case of deforestation, the critical point represents the point beyond which forests will shift from human-caused destruction to self-collapse, as forest fragments shrink and die due to the inherent instability of small forests fragments.

Now, it appears that the same equations fit the fragmented remains of the planet’s great rainforests. And that we’re getting close to the critical point.

This unexpected finding came about when researchers, led by mathematician Franziska Taubert, began combing through satellite images of the world’s entire remaining stock of tropical rainforest. But rather than simply count up the total area of intact forest that remains across millions of individual fragments, they counted the fragments themselves: how many there were and how much area each covered. While they expected to come away with different equations describing these rainforest fragments for each continent, they found instead that, across the world, the proportion of tiny fragments to large fragments was the same. Even more interesting, that proportion was exactly the ratio predicted by percolation theory.


jbdodane / Flickr

They followed the thread, developing a computer simulation of deforestation based on the equations, derived from percolation theory, and current rates of rainforest loss. The simulation results exactly matched the patterns Taubert and his team observed from the satellite data. The advantage of the simulation, though, was that it could go one step further – it could identify the level of deforestation that would push the world’s rainforests past the critical point. The result: at current rates of deforestation, tropical rainforest are only several years’ worth of deforestation away from smashing through the critical point.

To get a sense of what happens once deforestation surpasses the critical point, the research team played out their simulations in the Amazon basin. Just as in the case of an epidemic, the simulations predicted that the scale of deforestation would increase exponentially once the forest began to collapse on itself. By 2050, without an end to human deforestation, the overall area of the Amazon rainforest was predicted to drop by half. Even in a scenario in which reforestation was undertaken, but without concerted efforts to end deforestation, the rainforest fared little better.

Deforestation in Congo

CIFOR / Flickr

That's a bleak forecast considering how essential massive rainforests are to the planet as we know it. A 2015 study suggested that losing the world's tropical rainforests could not only cause nearly a degree of atmospheric warming, but could also dramatically alter rainfall patterns around the world. Without rainforests to serve as an atmospheric sponge around the equator, places as distant from the tropics as the United States' corn belt could see drought become commonplace. Closer to where the forests once stood, fires will run rampant as the land dries up. Tropical soils, without trees to turn over nutrients, will turn toxic to agriculture.

However, Taubert's team identified one scenario that offered a glimmer of hope. When the simulations assume that deforestation is phased out over the next decade and replaced with reforestation programs that increase each year, the Amazon would lose only one-quarter of its area over the next 30 years.

And while that still represents a staggering amount of lost rainforest, this outcome nonetheless demonstrates the immense power of conservation efforts to direct the future of the world’s rainforests. In that vein, this research and percolation theory itself are warnings, rather than death knells for tropical rainforests. Without action, both grassroots and government-driven, the time will come when rainforest fragments begin to collapse on themselves and it is too late to undo the damage. But that time has not yet passed.

Michael Graw studies



Oregon State University


]]> Mon, 12 Mar 2018 16:43:29 EST A gold rush in the Peruvian Amazon threatens to fill a vital and diverse ecosystem with mercury Bats are the canaries in the Amazonian goldmine Cassie Freund The highly biodiverse Peruvian Amazon appears as a verdant green blotch on any world map. But for global commodities traders, this area, particularly the region known as Madre de Dios in southeastern Peru, is best portrayed with a different color: gold. Peru's gold output has been steadily climbing alongside international gold prices for the past 15 years, and the country is now the sixth largest gold producer in the world.

This economic boom also comes at a monumental cost to environmental and human health in Madre de Dios, as deforestation rates have skyrocketed and mercury used in the gold mining process has begun to leach into the aquatic food chain. Now, a study by environmental geochemist Mónica Moreno-Brush, a PhD candidate at Germany's Technische Universität Braunschweig, and her Peruvian and German colleagues, published in January in the journal Ecotoxicology, indicates that the effects of gold mining in Madre de Dios are percolating into the terrestrial food chain and accumulating in Peruvian bats.

Most gold mining in Peru is carried out by individuals or small groups of people in a process known as artisanal and small-scale gold mining (AGSM). Virtually all AGSM is illegal. The Peruvian government has attempted to rein in the mining, but has had only limited success due, in part, to the sheer geographic spread of mining activities. And with tempting profits to be made – up to $2.6 billion per year, based on the 2015 United Nations World Drug Report – the AGSM industry has also been commandeered by powerful criminal groups, making combating illegal mining a dangerous endeavor.

Mercury and mining

The vast jungles of Madre de Dios, which teem with plant, animal, and insect life, are unfortunately being rapidly wiped off the map as a result. Miners cut down patches of rainforest in order to extract sediments and rock containing minute amounts of gold from the forest floor. They then mix the soil with water to create a muddy sludge and add mercury to extract minute gold particles. Mercury is a highly neurotoxic substance that binds with gold to form a small, solid mercury-gold ball, called an amalgam. The amalgam is finally heated over an open flame to vaporize the mercury, leaving behind a small pellet of gold.

Mining is dangerous and toxic work, but subsistence miners often see no other way to support their families. They take on massive health risks, working without masks or gloves to protect themselves from hazardous mercury exposure. Some even mix the slurry in barrels with their feet, much like the earliest winemakers smashed large vats of grapes.

Illegal mining

Ministerio del Ambiente del Perú / Flick

Unsurprisingly, the mercury used in AGSM now pollutes sensitive Amazonian aquatic ecosystems. Fish in Madre de Dios have been found to have elevated mercury levels. Consequently, people living in fishing villages along the Madre de Dios river - particularly members of isolated indigenous communities - are at high risk of mercury poisoning. In 2016 the Peruvian government declared a public health emergency in the region. And other wildlife in riverine food webs, like the charismatic giant river otters that live and feed in these increasingly mercury-laden waters, may be suffering ill effects as well.

Finding mercury's signature in rainforest bats, as Moreno-Brush and her colleagues did, is another new and worrisome side effect of gold mining.

Bat scan

They hypothesized that, if mercury waste from AGSM was being deposited into soil and vegetation, they would be able to see elevated mercury levels in hair samples from bats collected in Madre de Dios. On the surface, their choice of study animal may seem nonsensical: bats don't directly depend on aquatic food webs, where most previous research into AGSM had focused. And because they are highly mobile, they may be less susceptible to sustained exposure to mercury vapors in the air around mined areas.

But two aspects of bat ecology do put them at risk for mercury poisoning. First, bats have long life spans. Because mercury persists in mammalian tissues for years, long-lived animals progressively build up high levels of the potent neurotoxin in their tissues, a process called bioaccumulation. Pregnant women are discouraged from eating tuna, some of which can live for 40 years, for the same reason.

Carollia perspicillata

MarcoMello  / Flickr

Bats also eat a lot. Insectivorous bats can eat their body weight in bugs every single day. This means that, even if each insect only contains a minuscule amount of mercury, the chemical could quickly build up in bats' systems. In fact, one previous study – the only other piece of research examining mercury levels of tropical bats – found high mercury levels in insect-eating bats near a hydroelectric dam in Malaysia.

In Madre de Dios, the researchers found the highest concentrations of mercury in fur from bats captured closest to gold mining sites. Although the bats' mercury levels weren't above dangerous levels, and they did not show any neurological effects from the toxin, the results of this study are preliminary evidence that AGSM poses a serious threat not only to aquatic food webs, but to the terrestrial food web, too. And if the mining continues, mercury's ill effects will permeate every corner of this magnificent ecosystem.

Although AGSM may seem like a far away environmental problem, relegated solely to Madre de Dios, Senegal, or Indonesia, every one of us has likely contributed to the global demand for gold. Most is used in jewelry and electronics – in fact, if you're reading this on an iPhone, you're holding about $0.56 worth of gold in your hand right now. That demand is unlikely to diminish any time soon. 

mik_p / Flickr

Cleaning up the mess that AGSM has created will require large-scale ecosystem restoration, serious public health interventions, and community-based conservation initiatives. We need to find new sources of income for people who depend on mining for subsistence and identify effective methods for replanting the lost rainforest and cleaning up mercury-polluted soils. In Madre de Dios these efforts are being led the Centro de Innovación Científica Amazónica of Wake Forest University, an NGO founded by my doctoral advisor and his colleagues.

Just as each of us has contributed to the problem, we are each also capable of driving the solution by purchasing ethically sourced gold jewelry and buying fewer electronics. Although such small personal sacrifices pale in comparison to risks that Peruvian miners take to extract this precious metal from the earth, they are concrete steps that we can take toward protecting the health of Amazonian people, rainforests, and rivers.

Cassie Freund studies



Wake Forest University


]]> Tue, 06 Mar 2018 16:45:36 EST Why don't Americans care about chemicals? We need chemicals for daily life, but seem to feel 'apocalypse fatigue' around their dangers Anna Robuck For the past four years, researchers at Chapman University in Orange, CA have surveyed Americans to determine what we fear most. Polled at random, people were asked to rate their level of fear of about 80 different topics, including crime, terrorism, the government, environmental pollution, and personal fears. 

For the first time in 2017, environmental fears ranked with Americans' top 10 greatest fears: “pollution of oceans, rivers, and lakes,” “pollution of drinking water,” “global warming/climate change,” and “air pollution” all jumped into the top 10. They bumped perennial fears, about the economy, government, and terrorism, further down the list.

Increased concern about environmental pollution should not necessarily surprise us. In 2017, the Trump administration supported a market shift in US environmental policy and enforcement. That change has brought new attention to an old fact: we’ve created a whopping number and volume of chemicals over the years for use in industry and public health, somewhere around 140,000 formulations since 1950. Many of these chemicals can leach into the environment and into living creatures

Although relatively few chemical pollutants are thought to be harmful to human health, only a paltry 2 percent or so of extant chemicals have been well-vetted for safety and toxicity by the US Environmental Protection Agency. We're learning more every day about these significant levels of ambient contaminant exposure in the US, bringing this sort of pollution more into public awareness.

Carbon monoxide in the US

NASA Goddard Space Flight Center / Flickr

Though comparatively few in number, harmful synthetic chemicals can wreak havoc on public health around the globe. In 2015, an estimated 16 percent of all premature global deaths were caused by pollution and pollution-related disease, more than 15 times the number caused by war and all forms of violence combined. Ninety-two percent of these pollution-related deaths were in low- or middle-income countries, mostly related to air pollution. In the US, roughly 200,000 premature deaths each year are attributed to air pollution from combustion processes, like ground transportation and fossil fuel power.

Compelling evidence also suggests these chemicals impair the immune system and vaccine effectiveness, child brain development and learning ability, human fertility, weight loss, social behavior, cancer, and a slew of other diseases. You don't need to work in a chemical plant for high exposure: we encounter pollutants in everyday activities, in concentrations that have been demonstrated to be impactful, in the here and now of normal life.

A chemical Catch-22

Looking at these figures and facts, something seems amiss. We rely on power plants and manmade chemicals every day, and they are supposed to better our lives, not cut them short. But here we are, caught in a chemical Catch-22: some of these same chemicals we count on – for energy, medicine, food, technology – can harm us and wildlife when they're let loose, as they inevitably are.

Why do we allow chemicals to slip into our lives and bodies? Because it’s largely legal, at least in the US. Unlike more protective rules in Europe, chemical policy in the US errs away from the precautionary principle, which states that given two courses of action, with incomplete knowledge of the consequences, the more cautious approach should be followed. Under the 1976 Toxic Substances Control Act (TSCA) and a 2016 update of the law, the burden generally falls on scientists to prove chemicals are harmful, to humans or the environment, before regulators intervene; chemicals are assumed safe until proven guilty

Ken Douglas / Flickr

The dangers of new chemicals are evaluated according to new and existing rules that critics argue have been substantially weakened by the current administration; proponents argue that new emphasis on speedy chemical approval is good for business and still protective of public health, collecting increased fees from manufacturers to defray TSCA implementation costs. Regardless of individual TSCA opinion, the overall jump-first, think-later approach can be costly – in terms of health, lives, and money – yet the public has yet to demand significant revisions to chemical regulations in the US.

Working in contaminant research, I wrestle with our relationship to chemicals every day. I recognize how important modern chemicals are for public health and safety. Yet at the same time, I see environmental contaminants behind cancer in my loved ones, in snake-oil ads for new miracle products, or when a friend tells me over the phone that she just can’t conceive. On most days, these realities motivate me to keep working, to find ways to measure and understand pollutants – to learn more so that we might better understand or regulate the chemical cocktail all around us. 

But on bad days, I feel confused and frustrated and a little alone. Why is it so difficult for us to care about toxicants all around us, despite such dire consequences for ourselves and the people we love?

'Apocalypse fatigue'

Over the last two decades, psychologists have hypothesized that we respond – or don't – to faceless threats like climate change according to the way those threats are framed in contrast to the status quo. Economists, policy experts, and journalists have expounded on an outcome of this type of thinking, suggesting several terms to describe the phenomena: “threat fatigue," “resistance fatigue,” and “apocalypse fatigue” all roughly mean the same thing –that  we tire out from constant threats that challenge our modus operandi and thus don't take any of them seriously enough.

Per Espen Stoknes, a Norwegian psychologist and economist, suggests five mental defenses that stifle public engagement with the climate change: distance, doom, dissonance, denial, and identity. In a nutshell, we often see climate change as apocalyptic but far off, at odds with our accepted lifestyles. So we often deny our role in it or refuse to act, unwilling to confront what it means for our habits and identity.

If you listen to Stoknes' TED talk on the subject, you can substitute “synthetic chemical risk” almost everywhere he discusses climate change. Both are faceless, seem distant, and ostensibly require action outside of our routines: the same psychological and cultural barriers seem to influence how we see pollutants, and to neuter public concern and action. We may know that chemicals are all around us and may affect our health, but it seems like a minor threat, or one that is out of our hands, a danger beyond the actionable capabilities of any one person. These paralyzing assumptions mean chemicals keep getting introduced with little vetting. And people keep falling ill, sometimes fatally, as research struggles to catch up to how chemicals contribute to disease.

Where does this leave us?

The same solutions that encourage action on climate change may also help raise appropriate concern for chemical exposure. Stoknes suggests five approaches, readily transferable to our dilemma: discussing the issue in ways that make the threat personal; framing the issue in concrete ways – jobs, safety, etc – rather than global doomsday tidings; providing simple actions to make a difference; and finding better stories to break through denial or polarization.

Several organizations and many scientists are working on these goals already. Last winter, the journal PLOS released a special collection, “Challenges in Environmental Health: Closing the Gap between Evidence and Regulations,” in which a cast of experts filled the collection with short, easily understandable perspectives and essays.

The collection touched on the shortcomings of current law, what goes into our food, how toxicants affect children, how we can better protect drinking water, and a recent policy decision not to ban a pesticide. Each piece framed contaminant topics in terms of public health, policy, and solutions, going a step beyond sterile observations of most peer-reviewed articles. While the opinions were mostly of a kind, the expansive, interdisciplinary approach was both refreshing and riveting. Looking ahead, such holistic thinking is likely what's required from everyone.

What's in the food?

Jens Hembach / Flickr

Chemical regulation still faces resistance in the US. Even the collection's editor, Linda Birnbaum, the director of the National Institute of Environmental Health and Safety, was demonized by politicians who accused her of lobbying in her introduction. It can feel disheartening, but other, similarly accomplished scientists have started to speak out, too, including Joseph Allen from Harvard's T.H. Chan School of Public Health, and Richard Corsi from University of Texas. There are even new smartphone apps to better gauge individual exposure potential.

These figures set an example for how to discuss chemicals conversationally and to suggest consumer solutions with policy ones: we should try to tell better and more accurate stories, and to have an open mind. The results of the Chapman University study, indicating Americans today worry about environmental pollution, underscores the increasing effectiveness of more and better storytelling about pollution. 

I personally have witnessed a sea change in my own loved ones over the past few years; my mom and dad, far from environmentalists, now try to buy organic foods and tell others about chemical safety. Engaging in these sorts of honest conversations about chemical pollution benefits us all, and will hopefully create fair solutions that support public health, the environment, and the economy.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Mon, 05 Mar 2018 16:20:49 EST Climate change harms everyone's health. Yes, even yours No one evades global increases in extreme weather, disease, and injury Renee Salas There is consensus among experts that climate change is happening – and that it is playing a role in multiplying negative health impacts across the globe. These could exponentially increase as we approach the environmental tipping point scientists have warned us about.

However, a recent survey revealed that while the majority of Americans believe that climate change is causing harm, most do not believe that it is affecting them personally. They're wrong: climate change is already affecting all of us through negative impacts on our health independent of age, health status, socioeconomic class, or geographic location. Our personal health is intrinsically tied to the health of this planet, and the planet has a breathing problem.

For humans, breathing is the act of taking in oxygen and exhaling carbon dioxide. Adults do it an average of about 16 times a minute. In complementary symmetry, our planet has a "breathing" cycle that works in the exact opposite way: plants on land and plankton in water take in carbon dioxide and release our life-sustaining oxygen.

The harmony has been broken

But there's a growing amount of carbon dioxide with a decreasing amount of oxygen. This has been termed climate change because of the downstream effects this imbalance creates. Simply put, humans have produced more carbon dioxide through the burning of fossil fuels than the shrinking population of plants and plankton can compensate for. The harmony has been broken.

In a human, this sort of breathing distress would lead to death without medical intervention. As an emergency medicine physician, I encounter people when their health is threatened in this way. This can involve problems with not getting enough oxygen into the body, trouble getting the carbon dioxide out, or both. We must keep those levels in perfect harmony to survive, and the two are deeply interconnected.

The parts of the planet's breathing cycle, like our human one, are intertwined. Water cycles and weather patterns don't respect the man-made barriers that we call states or countries. Thus, carbon dioxide produced in one location has an effect on the opposite side of the globe. Oxygen on one side of the world will make it to the other side in a little over a year.

Tiananmen Square

James Riker / Flickr

This interconnection results in a true moral and ethical dilemma because the regions of the world that have produced the most carbon dioxide, and thus contributed the most to climate change, often have the fewest health impacts. Many people living in developed countries have food sources, houses, jobs, and city infrastructure that are not directly tied to the health of the land around them. The resources they are fortunate enough to benefit from creates a buffer.

Meanwhile in developing countries, livelihood is often directly intertwined with the land. People depend on their own crops for survival, live in fragile structures that cannot sustain extreme weather, and have jobs easily influenced by the natural world. This lack of resources creates an enormously small margin for adaptation in a world with climate change.

No exceptions

However, no one's health is entirely spared. The negative health impacts are numerous, complex, and arise in a variety of ways. On the most fundamental level, as carbon dioxide levels increase, there is a subsequent increase in global temperatures, sea level, and extreme weather.

This leads to such phenomena as extreme heat waves, environmental degradation, changes in where disease-carrying insects live, worsening air pollution, increased allergen production, decreased water quality, and decreased nutrition in crops. Sample impacts on health can be more heat-related illnesses, increased lyme and dengue infections, more asthma exacerbations, increased waterborne diseases, malnutrition, and mental health impacts. In its most severe form, people are forced from their homes; a displaced population faces more health challenges than perhaps any other. Extreme weather forced more than a million people from their homes in the United States in 2017 alone.

One of the easiest changes to recognize is increased heat, to which the kidneys and heart can be especially vulnerable. My patient Levi* was a 30-year-old Boston construction worker who was struggling to make ends meet as he cared for his family. Working overtime, he developed kidney failure after laboring intensely in the scorching summer heat. Though humans are inevitably adapting through an increasing resilience to heat, worsening extreme heat from climate change will likely result in more deaths in the future.

For many infectious diseases, factors that contribute to its spread - such as the geographic distribution of insects and their breeding seasons - are changing with climate change. In the US, lyme cases have more than doubled since 1990. My patient Jerod presented to the emergency department after having dismissed an earlier rash. However, after developing a severe headache and neck stiffness, he was diagnosed with lyme disease that had invaded his brain. We believe he contracted it from a region that didn't have lyme previously. Meanwhile, worldwide there are other infectious diseases that are increasing in incidence, such as dengue.

Breathing and injuries

Air pollution is also worsened by climate change, with urban centers being especially affected. Combine this with other factors like increased smoke from wildfires and increased allergen production, and those with underlying lung diseases experience more issues. One example is the meek four-year-old girl named Fang who was admitted to the hospital four times last spring for problems with her asthma. Or another patient I cared for some years ago in Haiti. Six-year-old Ricardo suffered many exacerbations of his asthma, likely from the perfect storm of severe air pollution in the city of Port-au-Prince coupled with rising temperatures. While living an ocean apart, their asthma responded to the same triggers.

The other impact of climate change that is most easily identified is injuries during or after increasingly extreme weather events, especially given the record-setting year of 2017. These events not only cause devastation locally; they can also have unexpected effects on health in far-off places. For example, there is now a shortage of IV fluids in the US. If you walk into an emergency department in Boston, you will likely not receive IV fluids unless you are significantly ill. The reason for this shortage is that Hurricane Maria devastated the production plants in Puerto Rico, yet another example of the true interconnectedness we have in this globalized world.

Just like air, climate change is ubiquitous. Thus, it affects every human on this planet. And as our planet struggles to "breathe" and maintain its health, our interconnectedness mandates that our health is equally in dire jeopardy. There are things that can be done today to help, but we must act before it is too late.

*Names were changed to protect patient identities.

Renee Salas studies

Emergency Medicine


Massachusetts General Hospital and Harvard University


]]> Tue, 20 Feb 2018 15:54:25 EST What Pokémon GO can teach conservationists about public engagement In six days, players collected as much data as naturalists had in 400 years Cassie Freund I don’t usually pay much attention to smartphone games, but earlier this week I read one of the most stunning facts I think I have ever read in a scientific paper: in a six-day span of 2016, Pokémon GO players collected so much data on virtual animals that it would take naturalists about 400 years to gather the same amount in real life. If conservationists could somehow generate this level of enthusiasm for our planet's real biodiversity, we just might be able to save the planet.

The field of conservation science is no stranger to leveraging technology to connect people with nature. The NGO Conservation International, for example, has developed two short virtual reality films to take viewers into the Amazonian jungle and underwater in Indonesia's Raja Ampat islands. Anyone can watch these films from their laptops or smartphones. National Geographic has followed suit with their own virtual reality short, "The Protectors," which lets the viewer experience what it's like to be in the Congo defending elephants from poachers.

Yet, conservationists have not created anything as wildly popular as Pokémon GO. I'm puzzled by how people can get so excited about virtual monsters while ignoring the urgent plights of the very real wildlife. Virtual reality films are a great start, but we need to do a lot more to translate the success of Pokémon GO, and the potential of augmented reality in general, into our efforts to document and protect wildlife. So, what are we doing wrong, and how can we fix it?

I don't think I'm the only one asking this question. Leejiah Dorward, lead author on the Pokémon GO paper and a PhD student at Oxford University, and his colleagues, attracted a lot of attention with their work: the paper, published in Conservation Letters, was one of the journal's most accessed articles in 2017.

The pika in Pikachu

One thing that Pokémon GO does well, and that conservationists can learn from, is that it teaches game players about ecology without being overtly educational. Many Pokémon look like real animals (have you ever noticed that Pikachu resembles a pika?) and can only be found in particular habitats. Their geographic distributions are limited by environmental characteristics like climate, distance to water, and soil type. Some species are common, some are rare, and some – like ice- and flying-type Pokémon Delibird – only appear seasonally. While I don't think that the game's creators set out to teach people about fundamental ecological principles, they've inadvertently done a great job. The parallels are so strong that Pokémon GO has already been used to teach ecology in some universities.

Pika Pika

David Kingham / Flickr

The mere act of playing the game also mirrors the scientific process. For example, the longer you play, the more types of Pokémon you encounter, and you are more likely to find relatively rare "species." Much like birdwatching, the game exploits into the human desire to collect and catalog things, a psychological lure unabashedly spelled out in the original Pokémon tagline, "Gotta catch 'em all!" Each time you catch a new type of Pokémon, it gets added to your Pokédex. And it can take a lot of patience, dedication, and fieldwork to actually catch all of the Pokémon.

Augmented reality is a major opportunity to leverage human psychology for nature's benefit. Video game creators have long understood how to manipulate the brain's dopamine response to keep us glued to our screens, and linking that nice jolt of neurotransmitters that we get from our screens to our deep psychological connection to the natural world would fundamentally change human beings' relationships to our planet.

Albert Hsieh / Flickr

This is where I think Pokémon GO-style augmented reality smartphone games for conservation could make a huge difference. But, unlike Dorward and his colleagues, I don't think integrating real animals into the existing Pokémon GO game is the best way to tackle the challenge. Instead, I envision a new augmented reality game, modeled after the Conservation International and National Geographic virtual reality films, that takes players on a series of virtual expeditions into Earth's most far-flung and biodiverse ecosystems.

Gotta catch 'em all

Similar to Pokémon GO, this game could be played from anywhere, and would be available to all 2.5 billion (and counting) of the world's smartphone users. All players would have access to all of the expeditions, but the abundances of wildlife that appear would change depending on the characteristics of each player's local environment. Instead of throwing Poké Balls at cartoon monsters, the player could fill the role of wildlife photographer, with the best photos entered into real international photo contests. Eventually, camera trap photos could even be integrated into the game, so that players could identify photos for research right in the game. Players might even earn points for real-life sustainable behavior, like picking up trash they encounter in their own environments while on the virtual expeditions. There are dozens of possibilities for possible game features.

Who is the true cartoon monster?

David Santaolalla / Flickr

Through such games, we can virtually expose players to ecosystems and wildlife that they may not have the opportunity to experience in person – as well as the things that threaten the existence of these places and species. Experiences are known to shape human behavior, and integrating this fact into wildlife conservation efforts might make a significant difference for the planet.

It's easy to wring our hands about "nature deficit disorder" and the fact that people today seem more interested in capturing virtual monsters than they are in protecting the actual animals around them. But I see this as our own failing in conservation. In an ever changing world, where many things are competing for people's time and attention, how do we keep nature relevant? The tools for innovation are at hand. Now it's our job to turn "gotta catch 'em all" into "gotta save 'em all."

Corrections: An earlier version of this article stated that the Pokémon Ghastly, and other ghost-type Pokémon, only appears seasonally. Ghastly appears year-round at night. Additionally, the article originally stated that players collected an amount equal 400 years of recorded specimens. It has been updated to reflect that the amount of Pokémon GO data collected was of the amount of data available in the Global Biodiversity Information Facility, which only reflects a small percentage of the world's documented specimens. 

Cassie Freund studies



Wake Forest University


]]> Wed, 07 Feb 2018 16:55:41 EST Can corals be saved? The key may be in their microbes Biologists are studying corals with techniques designed for humans Maite Ghazaleh Bucher Until the 1880s, people thought disease came from noxious air in homes, sewers, or haunted fields. Luckily, a German scientist, Robert Koch, introduced the germ theory and assigned bacteria to specific diseases such as cholera. Since then, we have learned that not all bacteria are harmful. As sequencing technology becomes more accessible, scientists are finding microbes everywhere: on our skin, in our guts, on plant leaves, on dog spit, even inside your coffeemaker. The microbes that we find are both good guys and bad guys – I’d say a majority are actually good guys. Bacteria function in our gut to break down our food and produce vitamins. Bacteria in plant roots protect the plant from disease.

Bacteria are also found in the oceans, both free-floating and living inside marine organisms. That includes coral reefs, where bacteria play equally diverse roles in the health and sickness of corals.

You can tell a coral is sick through visual signs such as black bands, dark spots, and white poxes that differ from the coral’s typically homogenous tissue. Inside this tissue, there are several thousand kinds of bacteria interacting with the coral. I began my PhD career studying diseased corals by measuring the abundance of the bacteria Vibrio, rod-shaped bacteria that are sometimes disease-causing. However, it was frustrating when not all sick corals had a high abundance of Vibrio in their system, or when I found a healthy coral that in fact did have Vibrio living inside of it.

Maite Ghazaleh Bucher

Other coral biologists have similar frustrations. Several bacteria or viruses have been isolated from diseased corals, and only a very small percentage have proven to directly cause a particular disease. I quickly learned that searching for one bacteria that causes a specific disease is close to impossible, especially since there are many bacteria present in both healthy and diseased corals.

So that is exactly what I set out to study for my PhD: the difference in the groups of bacteria that are present in healthy versus sick corals. The questions I try to answer are similar questions that human gut scientists answer: what microbes are present in healthy individuals, what microbes are present in diseased individuals, and what roles do these microbes play in disease development?

Gut microbiologists have discovered that some ailments, like irritable bowel syndrome (IBS), are not caused by a bacterial infection, but by a decrease in the number of good bacteria in the gut. General stress and unhealthy diets can also alter your gut microbiome and potentially cause IBS. 

Maite Ghazaleh Bucher

The bacteria in your mouth, too, maintain a healthy balance between many different types of bacteria that work together toward your oral health. Not flossing and intaking lots of sugar or fast food increases your chances of periodontal disease because you don’t remove the bad guys that thrive in anoxic pockets way down in between your teeth and gums.

There is a good possibility that corals that are getting sick are experiencing a change in their microbiome in a similar way that fast-food eaters experience a change in their gut microbiome: an outside stressor (bad lifestyle habit) shifts the microbiome to an unhealthy state. What if corals are getting sick because the healthy balance of microbes is thrown off by certain environmental stresses? Instead of looking at the presence or absence of a potentially pathogenic bacteria such as Vibrio, I started looking at the entire community of bacteria that live inside healthy and diseased corals.

By applying human microbiome research to coral disease research, I’ve found three patterns of microbiome-related disease that are similar between humans and corals:

  1. Gum disease can be studied by creating a ratio of bacteria correlated with healthy mouths to other bacteria correlated with diseased mouths. Scientists even found that an “in-between” ratio exists in healthy gum tissue of diseased mouths. This means periodontal disease is characterized by a succession in the types of bacteria. This is a promising way to study coral disease, because several papers have compared the entire microbial community between healthy, almost diseased, and diseased corals and have found that all three health statuses of coral have different microbial communities.
  2. Proteobacteria has been observed to abnormally expand in humans with metabolic disorders, inflammation, and cancer. This bloom of Proteobacteria compromises the ability to maintain a balanced gut microbial community. Attempting to describe coral bacteria in this way is also promising – my lab has observed that Vibrio bacteria bloom in Florida Keys water after Saharan dust storms. The Vibrio that rapidly increase in abundance may out-compete the beneficial bacteria from colonizing the coral, and make the coral more prone to getting sick.
  3. People with inflamed sinuses could be missing key bacteria that maintain the peace inside your nose. This causes the microbial network to become fragmented, meaning the microbes don’t function well together anymore. Some coral laboratories have observed Endozoicomonas is abundant in healthy corals but not in diseased corals that might be missing this key member of its healthy microbiome.

Fifty percent of the world’s corals have been lost in the last 30 years, and a shocking 80 to 90 percent of Florida's reefs alone are already devastated due to environmental stress such as warmer waters and nutrient pollution. To save our coral reefs from further destruction, we coral biologists are getting creative with the research connections we make. By using examples in human microbiome research, I hope that we’ll more quickly understand coral disease development and protect our global reefs from future harm.

Maite Ghazaleh Bucher studies

Environmental Health


University of Georgia


]]> Mon, 05 Feb 2018 10:22:10 EST Creationism helped push climate skepticism into classrooms Science education has become a political issue, but civic engagement can still work wonders Julia York When I moved to Texas last year, I had no idea creationism was still taught in science classrooms. I learned about its persistence when, with a group of researchers from the University of Texas, I testified for the State Board of Education. The board was "streamlining" science standards, and had incorporated language in the evolution standards directly from the creationist movement. The hearing was a firsthand glimpse at how this movement has been so successful in their efforts to make evolution controversial.

When we arrived to testify, we found others ready to speak their minds: one or two angry parents, who snapped about religion having no place in science class, and representatives of conservative thinktanks, who quietly discussed specific clauses and phrasing of the standards, never mentioning evolution or creationism explicitly. These representatives are from religiously motivated “institutes” that argue the science on evolution is not settled. In 2009, the state board agreed to their appeals to examine “all sides of scientific evidence” when teaching evolution, despite the fact that evidence does not have sides.

Growing skepticism toward science

These advocacy groups have successfully pushed this argument in several states, even while consistently losing major court cases since the founding of creation science in 1963. In fact, polls suggest many Americans still doubt natural selection. A 2015 Pew report found that, although 62 percent of Americans believe humans evolved over time, only 33 percent believe that life evolved solely through natural processes. And in 2005 only 40 percent of Americans said they accepted the idea of evolution, down from 45 percent in 1985. 

Of community college biology students in Texas, 85 percent reported having spent five hours or less learning about evolution. Sixty-four percent of biology students at the University of Minnesota reported that their high school biology course taught both creationism and evolution, likely violating court rulings that rule a "balanced treatment" unconstitutional.

The Scopes 'monkey trial' of 1925

Smithsonian Institution @ Flickr Commons

Now similar groups are trying to apply this strategy to how climate change is taught. Only 50 percent of Americans believe humans are the major cause of climate change; the lowest of all nations in a 2014 poll. According to a 2016 Science study, 71 percent of science teachers teach about recent climate change for at least one hour, and report teaching climate change for 5.5 hours on average. However, 30 percent of those teachers emphasized that climate change is due to natural causes, and 31 percent reported that they explicitly teach “both sides” of the climate change debate.

Faith, science, and politics

Since the 1920s, the creationist movement has increasingly bound its beliefs on evolution with political beliefs. Creationism is taught in American science classrooms in part because its adherents believe evolution conflicts with a literal interpretation of the Bible, and therefore conflicts with some strains of Christian ideology and belief.

Polls show climate change, similarly, has become an issue tied to ideology and partisan politics despite efforts to convince evangelical Christians climate change is a Christian issue. The best predictor of whether a teacher chose to “teach both sides” of climate change, according to the Science study, was whether they agreed with the statement “it’s not the government’s business to protect people from themselves.”

The Creationist Museum

 Jelson25 / Public domain

Students and teachers report that teachers avoid controversial topics for several reasons: they fear parent reaction; receive little or no support from administrators; and feel ignorant of the subjects and whether there is scientific consensus. For all the talk of "controversy," over 95 percent of scientists prefer to teach only evolution and over 97 percent of scientists accept human-caused climate change. Yet only 45 percent of high school science teachers believed greater than 80 percent of scientists accept human-caused climate change.

In the American education system, written standards are compiled for each subject; these standards determine what goes in textbooks and how much a student is expected to learn in each grade. Schools and teachers thus design curricula to reach that end. Education officials have different methods in different states, but in each, the statewide standards are determined by Boards of Education. In 24 states, elections decide either a proportion of or the entire board; in other states the governor generally has power to appoint members. In both cases, there are little to no qualifications required. 

In Texas, board members are some of the state's most powerful elected representatives, representing more people than state senators or congressional representatives. Their mission, according to the National Association of State Boards of Education, is to incorporate the concerns of the public, policymakers, business leaders, and civic groups into educational standards, graduate requirements, and accreditation and qualification requirements.

'Academic freedom'

Since the 2016 election, state leaders have proposed a new wave of bills and resolutions that would allow greater “academic freedom” in science classrooms. In practice, these would encourage teachers who are already inclined to teach dissenting and "diverse" views on what is otherwise basic consensus science.

In Florida, for instance, lawmakers passed a law last July that allows any resident to object to classroom materials. It was passed with support by the Florida Citizens Alliance, a conservative group, one of whose leaders told PBS they intend to show how textbooks have a “bias towards Islam and seldom mention Christianity," and that “Darwin’s theory is a theory, and the biblical view is a theory, and our kids should be taught both in a balanced way.”

The American Museum of Natural History

Dom Dada / Flickr

Idaho lawmakers took an even more direct approach. Last February, the state legislature voted to reject new science standards, the first since 2001, because Republican representatives disapproved of new terms about climate change and the role of human activity.

Meanwhile, a conservative thinktank named the Heartland Institute has cast its efforts nationwide. The organization published a report by what it calls the "Nongovernmental International Panel on Climate Change" (a riff on the Intergovernmental Panel on Climate Change, or IPCC, which publishes periodic reports on climate science, most recently in 2014). This “NIPCC” report, written by three scientists, argues that carbon dioxide cannot be driving global warming and that the IPCC reports, written by 831 scientists, are biased and not credible. The Heartland Institute has mailed its report to 300,000 public school teachers, along with a DVD and a letter encouraging the use of the materials in classrooms.

Getting involved

To counter these campaigns to remove science from public classrooms, we need people to show up and argue for the inclusion of climate change in school standards. Before I appeared before the Board of Education, testifying was intimidating. Afterward, I realized that by calmly stating my qualifications, the scientific evidence, and my opinion, I helped to push the board to remove some of the creationist language from its standards last year.

You can get involved with your state board, too – and it's their job to hear you out. From my experience, I learned several things: 

  • Be specific; often the board is only considering a specific piece of proposed language, so frame your argument around why or why not that language should be adopted. There's no need to grandstand on general principles. 
  • Stay calm; these meetings can draw out a lot of passions, but getting angry or loud only allows people to dismiss your ideas. 
  • Bring written copies of your statement, and any additional evidence or documentation for each member of the board – and for some of the office staff who supply documents and influence the board members. 
  • Pay attention to the time limit; often you are given only a few minutes to testify, and you will be cut off. 
  • Pat yourself on the back! Getting involved really pushes the boards to be better. If you are feeling hesitant and in need of support, try reaching out to a local nonprofit or community group, which might be able to help you get started.

These efforts are important: evidence suggests the best predictor of whether a high school student believes human activities cause climate change is whether their high school science teacher believes climate change exists at all – regardless of that teacher's belief in human causes. Adolescents are influenced by skepticism they perceive in their peers and parents, but with climate education, at any level, they are better than adults at evaluating evidence independent of ideology. The key, therefore, is to ensure that teachers include climate change in their lessons. 

We can't let American acceptance of climate change fall further just as the effects of climate change accelerate all around us.

Julia York studies

Polar Science


University of Texas at Austin


]]> Mon, 29 Jan 2018 18:00:59 EST Low doses of contaminants, long ignored, can have vast consequences Scientists found cocaine – and a lot of other chemicals – in Minnesota snow Anna Robuck In 2016, four billion prescriptions were filled within the US. That's about 12 prescriptions filled per US citizen over the course of a single year.

Although hugely beneficial in terms of public health and longevity, manmade pharmaceuticals and other compounds have downsides that are typically out of sight, out of mind. At the tippy top of the "con" list rests "environmental persistence" – as the enormous volume of manmade pharmaceuticals and chemicals produced and consumed each year doesn't *poof* and disappear after humans consume or use a given compound. Pharmaceuticals and other human pollutants stick around for minutes, days, weeks, years, decades, or even millennia in the environment, and have a sneaky way of showing up where they aren't welcome.

Like in snow. A recently published study by Mark Ferrey of the Minnesota Pollution Control Agency and colleagues found man-made contaminants like pharmaceuticals, surface-coating chemicals, and cocaine in snow from Minnesota. Alarming? Yes. Dangerous? Probably not, as the pollutant levels found were, thankfully, quite low.

Yet low doesn't translate to negligible. Seventeen emerging human contaminants were found in Minnesotan air, rain, and snow. Emerging contaminants (ECs) are created compounds that are relatively new on the scene and are understudied in terms of their chronic ecological and human health impacts. Compounds found in the snow included alkylphenols – used in surfactants and soaps – derivatives of benzotrioles used in anti-corrosive coatings, caffeine, several antibiotics, an x-ray contrasting agent, cocaine, and the active ingredient from household insect repellants, DEET.

The concentrations found in this study are in the parts per billion (ppb) to parts per trillion (ppt), ranging from below detection limits to approximately 228 ppt. A typical therapeutic pharmaceutical dose is somewhere in the parts per million (ppm) range, meaning exposure to the concentrations found in snow and rain as documented in Ferrey’s study are very, very unlikely to cause acute effects in humans or wildlife.

But here's the rub: pharmaceuticals and other ECs are created to be biologically active at low doses, and have been found to accumulate in the environment or living organisms more than we thought possible. Toxicity testing currently centers around lethality or observed acute effects in a lab setting and doesn't account for chronic effects from continued low-level exposures or complicating real-world conditions. Just because an organism doesn’t go belly up doesn’t mean its chemical environment isn’t impacting it, and such assessments underestimate or miss what low EC concentrations can do in living systems over extended periods of time.

Unfortunately, chronic harm from low EC concentrations isn’t just a hypothesis. Synthetic hormones have been found to cause collapse of fish populations with prolonged exposure to amounts as low as five to six ppt in surface water. Environmentally relevant concentrations of ECs have been found to change how fish eat, alter predator-prey dynamics, suppress respiration or primary productivity, or skew fish population sex ratios.

While the impacts of chronic low concentrations of ECs may be surprising, Ferrey and his team noted that finding these compounds in snow isn’t necessarily surprising. The presence of ECs in natural water bodies is well-established. A 2002 study in the US found that 80 percent of US streams contained detectable concentrations of pharmaceuticals or other personal care products. More recently, EC concentrations in the ppb – ppt range have been found within freshwater, estuarine, and coastal bodies of water across the US and globe. ECs have also been detected in air and rain, confirming these compounds are capable of jumping into the atmosphere from surface water source areas. Finding ECs in snow is just an additional line of evidence that atmospheric transport of these compounds is a viable pathway contributing to their ubiquity in the environment today.

The chemical cake

When I bring up pharmaceuticals in water or air as part of conversation, I’ve gotten asked what other conspiracy theories I believe in, heard imitations of Alex Jones and his ridiculous frog theory, or received a glazed smile and nod. To me, such responses are symptomatic of a larger lack of concern about ECs; there’s scant public outcry about understudied synthetic chemicals in air and water despite the fact that production and diversification of human-created chemicals have outpaced every other identified agent of global change, particularly in developed countries.

Decreased EC research and popular attention may relate to less-than-perfect assumptions about them, particularly pharmaceuticals. Decades of meticulous research are required to show pharmaceutical structure, function, and fate within the human body before it's approved for public use, but environmental fate is less thoroughly vetted. Instead, scientists often rely 'quantitative structure activity relationships' and lab testing to make predictions about a chemical's fate. This involves using established empirical data to estimate a compound's biological impacts and environmental fate based on its structure, and then validating these assumptions in a controlled laboratory environment. It’s cost-effective and provides good insight, yet it’s not a perfect approach: these sorts of educated deductions inform assumptions of EC environmental fate and biological impact, rather than comprehensive in situ data collection.

As a result, many ECs have been thought to degrade too readily in the environment to impart harm or be transported any significant distance in air or water. Results like Ferrey’s, and additional observational evidence suggesting we have underestimated the persistence of ECs, mean that their atmospheric and water-based transport cannot be written off as unlikely or insignificant.

The icing on the chemical cake is the phenomenon known as mixture toxicity. We are inundated with synthetic chemicals on a daily basis, and have faint idea how all these small ambient exposures add up. Research suggests that sustained, low-dose exposures to complex mixtures of pharmaceuticals, ECs, and other pollutants may impact humans or wildlife in sublethal, chronic ways we have yet to fully understand and can’t really predict from toxicity testing focusing on the limited effects of one type of chemical in one or two types of study organisms.

'Divide and conquer'

To even begin understanding the ramifications of chronic EC exposures or mixture toxicity, researchers must be able to measure pollutant concentrations. Ferrey's study used a combination of two analytical techniques, chromatography and mass spectrometry, to measure pollutant concentrations in carefully prepared water and air samples. The two techniques are a chemical equivalent of "divide and conquer," as in combination they act to separate different compounds from each other to allow identification by weight.

The methods and analysis employed in this work aren’t groundbreaking. Environmental chemists the world over use similar approaches to prepare environmental samples and screen them for various pollutants. But it's expensive and time-consuming. Coupled chromatography/mass spectrometry systems are pricey, running anywhere from around $100,000 to north of $500,000, effectively limiting use to those agencies or institutions who can afford them, or afford to pay for sample analysis elsewhere.

Lack of systemic access to appropriate measurement instrumentation means for most of the globe, ambient concentrations of pharmaceuticals and other ECs remains a big, fat question mark. This isn't cause for mass hysteria, as no one can claim they are getting viable doses of medication from a dip in their local water body. But, we do know that low concentrations of ECs have both local and far-reaching ecological consequences that are mostly under the radar, to the detriment of humans and wildlife.

Although we certainly can't do away with pharmaceuticals or other life-saving compounds, seek out personal care products with environmentally safe active chemical ingredients and refrain from flushing any prescriptions down the drain to prevent contributing to ECs in your waterways, air, and winter's swirling snowflakes.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Mon, 29 Jan 2018 09:26:05 EST To predict the future of Southern California's seas, scientists are looking to the past The west's dramatic coastlines have masked rising tides, but that doesn’t mean the future is dry Elisa Bonnin Much of the concern in the US about how much climate change will cause oceans to rise has been focused on the East Coast, neglecting Southern California, home to two of the country's five most populous cities.

The East Coast has been the focus of sea level rise studies in the past because of the gentle rise of the continental slope there. In that part of the country, a small rise in sea level can cover a much larger area, and we know just by looking at these slopes that cities on the East and Gulf Coasts of the United States – Miami, New Orleans, and New York City, for example – will be more heavily impacted by sea level rise than their western counterparts. But while the West's dramatic coastlines have masked the effects of sea level rise up to this point, that doesn’t mean that the West Coast will get off free and clear.

Under the Santa Monica pier

Riley Kaminer / Flickr

With both of Southern California's biggest cities built around the coast, sea level rise is still a threat, and without good predictions about just how high the sea will rise, civil engineers and city planners are working blind. Predicting sea level rise is a difficult, because we simply have never seen sea level rise at this scale before. We are changing Earth’s climate at a rate unprecedented throughout all of human history.

But not, it turns out, throughout Earth's history. Sea level has risen and fallen on the planet before, we just weren’t around to see it. So when it comes to predicting the effects of modern climate change, scientists often have to act as detectives. We weren’t there to witness these changes. All we can do is look at the evidence left behind, and use it to piece together what happened. That’s where foraminifera come in.

Enter the plankton

Foraminifera, or "forams" for short, are microscopic plankton that live in the ocean. They create their shells out of a hard mineral called calcite, and they are preserved as fossils long after the organism dies. Because these small creatures live everywhere in the ocean, from the surface of the water to the seafloor, they are some of oceanographers’ most valuable tools for understanding past climates. A group of researchers from UCLA, led by postdoc Simona Avnaim-Katav, think that one kind of forams can tell us how sea level changed in the region in the past – and, therefore, what we might expect in the future.

Needlefish and plankton

Tom Verre  / Flickr

Avnaim-Katav looks at forams that live in salt marshes, coastal areas with a pretty dramatic slope, where sea level changes with the tide. In areas like these, different species of foraminifera tend to live at different elevations. They prefer varying light levels, pressures, and salt content, all of which can change with water depth.

In order to understand sea level changes in the region, Avnaim-Katav and her team went out to two salt marshes relatively untouched by human development, one at Seal Beach, California, and the other in the Tijuana River Estuary, in San Diego County. They collected 57 surface sediment samples from different elevations along the coast and looked through each of them to determine which species were living at which elevations.

Census of the sea

From that data, they created what’s known as a species assemblage – a census, basically. They took notes of water depth, temperature, salinity and oxygen, along with a list of which species were living at which sites. Their goal was to create a transfer function, a computer algorithm that could be used to predict water depth based on the species that lived there.


Marc de Ruijter  / Flickr

It works something like this: if Species A and B like shallow water, and species B and C prefer deep water, we can predict that a sediment sample from 20,000 years ago that contains species B and C must have been in deep water, even if it’s found in shallow water now. This is a common technique for determining sea level changes, and has been used in multiple sites all around the world, but never before in Southern California. In order to create this transfer function, the biggest question that Avnaim-Katav had to answer was whether the forams there were impacted by elevation at all.

Tijuana to Seal Beach

To do this, they had to turn to statistics. They used an impressive collection of statistical tests to see if elevation was the strongest predictor of species assemblage, or whether it was something else, like salinity, pH, temperature, or oxygen concentrations.

At Tijuana, they found what they were hoping to see. Elevation explained 43.2 percent of the differences between species, with the other parameters sharing the remaining 60 percent. At Seal Beach, however, the story was a little different. Elevation in that region only explains about 16 percent of the species differences, with oxygen being the parameter that most affects where species live. However, when the results from the two beaches are combined, elevation comes out on top, allowing them to produce a transfer function that, while not quite perfect, can give us much more information than we currently have.

And as far as this research goes, this is just the beginning. Avnaim-Katav and her team haven’t figured out how sea level has changed, and they still don’t know how drastically the sea level in Southern California will change in the future. But they’ve figured out how to answer those questions. They’ve developed the pathway that will allow them or future researchers to tackle this problem, bringing us one step closer to adapting to sea level change.

Elisa Bonnin studies



University of Washington


]]> Tue, 23 Jan 2018 16:55:33 EST Scientists were long baffled by a methane surplus in our atmosphere. The culprit: trees It's not just flatulent cows Cassie Freund Tracking the movement of chemical compounds between Earth's land, water, and atmosphere is like balancing a checkbook, an action that most of us are, at least, passingly familiar with. Ideally, you should be able to account for all of your money at any given time. And if the amount you think you should have in your bank account doesn't match what the bank says you actually have, you're probably wracking your brain trying to account for the missing funds.

Similarly, scientists who study greenhouse gases have long been trying to work out the Earth's methane budget: How much is in the atmosphere? How much is being absorbed and emitted by living things each year? And, importantly, where is it all coming from?

Though ecologists have learned a lot about the contribution of plants, animals, and soils to the methane cycle in the past few decades, they've remained stumped by a persistent budget shortfall: more methane was present in the atmosphere than they could account for by their soil and water emissions estimates alone. Now, two new studies, one by a group of European and Brazilian scientists led by Sunitha Pangala from the Open University in the UK, and the other headed by my colleague Mary Jane Carmichael and her team at Wake Forest University, have reconciled the long-imbalanced methane budget. The missing link: trees.

Cracks in the earth, gassy cows, and trees

Methane stays in the atmosphere for just nine to 15 years before it is broken down by sunlight or sucked back up by plants and bacteria. But during that time, it is about 30 times more efficient at trapping heat in the atmosphere than carbon dioxide is. 

There are several natural sources of methane: some escapes from stockpiles deep in the earth's crust, which is what we humans tap for energy in the form of natural gas. Another source is livestock – essentially, burps and flatulence from ruminant animals, mainly cows. And about 30 percent of the world's methane is emitted from wetlands, critically important ecosystems that cover just 5 percent of the earth's surface.

Ruminating ruminants 

Unsplash /  Stijn te Strake

Until now, a majority of scientists thought that most methane flux in wetlands followed two pathways: through the water and through the soil. Wetlands are chock-full of slowly decomposing plant and animal matter, and methane is slowly released as microbes break down the dead stuff. Ecologists have known for many years that plants can produce and transport methane, but vegetation had not previously been incorporated as a significant source in the global methane budget. An impetus for changing scientific thinking came in 2012, when a team of scientists also led by Dr. Pangala sampled a small area of tropical peat swamp forest in southeast Asia and found that methane transmission through trees accounted for 62 to 87 percent of local methane cycling.

The physiological adaptations that enable wetland trees to survive in flooded ecosystems seem to be the very things making them such efficient methane emitters. In general, trees living in flooded habitats have enlarged pores (called lenticels) in their stems that allow them to take in extra oxygen when water levels are high. They also have hollow tissues that enable them to easily transport the oxygen within their structures. These features are two-way streets, meaning if oxygen can easily flow into the tree, methane and other gases on the inside can also escape.

Wetlands in Taiwan

@tsaiga / Unsplash

That initial small-scale study in Asia in 2012 set the stage for Pangala's latest research in the Brazilian Amazon, published in December in Nature. Brazil's vast expanses of tropical forest nestled in the winding tributaries of the Amazon River make this region exceptionally rich in forested floodplains. By measuring methane emissions from 2,357 trees at 13 separate locations, Pangala and her team calculated that floodplain trees emit 15-21 teragrams (trillion grams) of methane, an amount roughly equal to the gap in the Amazonian methane budget. They also found that, based on their revised tallies, the soil, water, and trees that make up the central Amazonian floodplains account for about 15 percent of total global methane emissions.

While Pangala was searching for rogue methane emissions in the Amazon, then-PhD student (now Dr.) Mary Jane Carmichael was exploring another take on the idea of trees as conduits for methane emissions in her study site in a restored wetland on North Carolina's Albemarle-Pamlico peninsula. Carmichael and her colleagues knew from Pangala's work that living trees transferred methane from wetlands into the atmosphere, and they wondered if dead trees might also perform the same function. The results, published in the journal Wetlands in October, affirm that dead trees do indeed merit their own line item in the global methane budget.

Measuring how much gas flows through dead standing trees in waist-high water is no easy feat. First, Carmichael and team drilled holes in the hollow tree trunks and collected gas samples from inside to determine whether more methane was accumulating inside of the trunks than was present in the air surrounding the trees. Then, using small flux chambers attached to the tree trunks, they measured how much methane was actually flowing through the trunk into the air. Both tests confirmed that Carmichael's hunch was correct: dead trees are another pathway for methane emissions from wetlands. Their hollow trunks essentially act like straws poked into the ground, releasing a slow leak of the greenhouse gas into the atmosphere.

Trees like straws

Geoff Livingston / Flickr

Although methane emissions are often reported solely in the context of climate change, it is important to note that methane is not inherently good or bad. The problem is that human activity is rapidly increasing its concentration in our atmosphere, and that will have negative consequences for all life on earth. These two studies, which identify previously unknown mechanisms for how the methane that is is already in our atmosphere got there in the first place, represent leaps forward in our understanding of global methane cycling and our ability to track methane flows through wetlands and other ecosystems.

The race is on: wetlands face a myriad of conservation threats, and although they emit some methane through natural processes, they also do us a huge service in that they store tremendous amounts of carbon dioxide. The hope is that charting the global cycling of greenhouse gases can help us pinpoint new and clever ways to mitigate climate change, just as you might be able to pinpoint ways to save some hard-earned money by monitoring what you spend your cash on each month. With global emissions jumping up 2 percent in 2017, a year deemed by NASA to be the second-warmest year in recorded history, we have no time to waste.

Cassie Freund studies



Wake Forest University


]]> Mon, 15 Jan 2018 10:28:02 EST What does California's future look like? Scientists asked trees Blue oaks have up to 500 years of climate history written in their rings Daniel Ackerman The wildfires that torched California last fall came right on the heels of another calamity, a five-year drought that was finally washed away in early 2017. Much ink has been spilled trying to pin these extreme weather patterns on human-caused climate change, but such debates raise an even more basic question: how “extreme” are these events? Was this drought really that rare in notoriously arid California?

The answer is tricky. To make a well-educated guess at how often prolonged droughts have occurred in California’s past we would need centuries, if not a millennium, of climate data. Unfortunately, humans haven’t been measuring precipitation and temperature for that long. But thankfully, someone else has.

Ask the trees

Blue Oak trees stretch out their broad limbs, as if awakening from a long nap, over the scrubby foothills that ring California’s Central Valley. These trees have lived here for thousands of years, and despite being rooted in place, they are far from asleep. In fact, Blue Oaks are keen observers of climate conditions in the region. They write that story in a series of concentric rings inscribed within their trunk, adding a new line each year to stay current.

A blue oak in California

Yath / Wikimedia commons

Daniel Griffin has built his career by reading these stories, the central activity in the field of dendrochronology (in Latin, the study of “wood-time”). Griffin, a physical geographer at the University of Minnesota, studies the size of annual rings to understand how climate drives tree growth.

“Blue oaks have an almost one-to-one relationship with precipitation,” Griffin said. He attributes the strength of this relationship to the timing of their growing season, in spring immediately after the rainy season. In years when water is plentiful, the trees soak it up and build a sturdy, fat ring.

Plus, Blue Oaks are long-lived. “Individuals routinely live to be 200 to 300 years old,” Griffin said, “and in exceptional cases at least 400 to 550.”

However, Griffin cautioned that it can be difficult to estimate a Blue Oak’s maximum age. The wood at the center of the trunk, containing the trees' oldest rings, is prone to rot. 

Still, Blue Oaks’ longevity and sensitivity to moisture popped into Griffin’s mind when he began hearing about the extraordinary severity of California’s recent drought.

A blue oak in California

Miguel Vieira / Flickr

“In early 2014 I started seeing news reports that this might be the worst drought for 500 years in California,” he said. “I was suspicious.”

Griffin has researched the arid climate of California for decades, and he knew that periodic droughts in the region were the rule, rather than the exception. “I had been involved with tree ring studies of hydroclimate in California since the early 2000s,” said Griffin. When confronted with the idea that the recent drought was off the charts, “I just didn’t believe it,” he said. So he asked the trees.

Reading in the rings

Griffin and a colleague, Kevin Anchukaitis, collected pencil-thin cores from living Blue Oaks, as well as cross sections from stumps of trees that have been dead for decades or centuries. By matching up the patterns of wide and narrow rings among their samples, living and dead, Griffin created a 1,200-year chronology of Blue Oak growth in California. In some years, large growth rings across all the samples indicated excellent moisture conditions for the trees. In other years, called “pointer years,” dry conditions caused tiny rings, sometimes only a couple cell layers thick.

Griffin has these pointer years memorized, a dendrochronologist’s party trick. “1580, 1613, 1654, 1795…” he recited, “There’s a long list of these individual years that were really hard on all the trees.”

But to determine whether any past droughts, indicated by poor tree growth, were more severe than the California drought as of 2018, Griffin had to get quantitative. Griffin carefully measured the exact width of every annual growth ring from his samples, and then correlated ring size with rainfall for each year in the past century, when precipitation has been measured directly.


Once he calibrated this relationship between tree growth and precipitation, Griffin could use the size of the Blue Oak rings to estimate precipitation for the entire 1,200-year length of his tree ring chronology.

The trees revealed that the 2012-14 drought period was not the driest in the last millennium in terms of precipitation. Two separate spans, each lasting three years, had even less rainfall: 1898-1900 and 1527-1529. 

However, precipitation doesn’t tell the whole story of a drought. High temperatures accelerate the evaporation of what little moisture might be available to plants in the soil, and California has warmed in recent decades.

"Temperature is playing an increasing role in soil moisture and water balance," Griffin said.

So he and Anchukaitis decided to re-run their analysis using another environmental variable besides precipitation. They chose the Palmer Drought Severity Index (PDSI), an estimate of soil moisture that accounts for the combined effects of precipitation and temperature. Compared to precipitation alone, PDSI paints a more realistic picture of drought as experienced by Blue Oak trees – or humans, for that matter.

In terms of PDSI, Griffin and Anchukaitis found that the 2012-2014 drought was the most severe three-year span in the last millennium in California. Soils in 2014 were drier than any single year in the 1,200-year tree growth chronology. California's recent drought was a truly extreme event, even before it stretched into 2015 and 2016. The high temperature was something different about this particular drought,” Griffin said.

Peering into the future

High temperatures will be here to stay as the global climate continues to warm. Droughts of this severity, though unprecedented so far, may become a regular feature of California’s human-altered climate. Griffin believes water resource planners and engineers should take note.

“This is the type of [drought] that we expect in the future,” Griffin said. “It would make a lot of sense to realign our expectations of ‘normal’ in California and plan for some of the worst that we’ve seen in the record, including this event.”

Half Dome by wildfire

LizzyH95  / Flickr

Blue Oaks told us that the recent California drought was truly exceptional, and they are hardly the only trees with stories to tell. Similar studies could potentially yield historical context for last fall’s wildfires, too – scars in tree trunks can help reconstruct the extent and timing of past fires.

Trees have been growing for far longer than humans have been measuring the climate. They provide valuable proxies for environmental change, helping to contextualize our own experience in a warming world. Other climate archives, like cores sampled from ocean sediments or ice sheets, can provide similar information on an even longer time scale. 

By looking to the past, and the organisms that have lived it, we can try to understand – and plan for – how anomalous our human-altered future is becoming.

Daniel Ackerman studies



University of Minnesota


]]> Wed, 10 Jan 2018 14:26:12 EST What the Ice Age tells us about how plants will manage in a hotter world New research seems to resolve a puzzle of why plants struggled in the past Baird Langenbrunner When I started writing this article, I decided to prepare by (re)watching the first animated Ice Age movie.




A sleeping giant




Doubt on dry ice


Glacier Car Park, New Zealand

Unsplash / Will Turner



Paradox lost



Torres del Paine National Park, Chile

Unsplash / Olga Staska


Carbon starvation




Baird Langenbrunner studies

Earth System Science


UC Irvine


]]> Thu, 04 Jan 2018 09:00:22 EST Is light pollution changing how plants do – and don't – grow? Plants depend on cycles of light. Now, they're always on Kylla Benes Every living thing has rhythm. It doesn’t matter if it’s a single-celled microbe or complex creatures such as ourselves – activities occur according to daily, seasonal, and even lunar cycles.

These cycles are usually synchronized by light. Therefore, a potential hazard to natural rhythms is light pollution, or as scientists call it, artificial light at night (ALAN). Although there have been efforts to reduce ALAN, light pollution has increased both in terms of brightness and land area cover, respectively up 1.8 percent and 2.2 percent per year since 2012. In humans, exposure to artificial light at night is associated with a myriad of health problems such as sleep disorders, depression, and certain types of cancer. Plants can also be affected by light pollution, and we are just beginning to understand how.

Plants depend on light for energy. They gather sunlight in microscopic, chemical solar panels called chloroplasts. The light energy moves through a series of chemical reactions that turn carbon dioxide into usable energy, like glucose, in a process called photosynthesis. With few exceptions, plants are the only type of organisms that can directly use solar energy to make their own food. Because of this, it is easy to think that light pollution should have an overall positive effect on plants. Increased light should mean more photosynthesis, giving plants more chemical energy for growth and other functions.

But more growth isn’t what scientists always find. In a study recently published in Limnology and Oceanography, Maja Grubisic of the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and colleagues found that light pollution may actually inhibit growth of aquatic microscopic plant communities called periphyton.

Over a three-week experiment, exposure to the increasingly popular LED lighting reduced periphyton by more than half compared to controls, which received no artificial nighttime lighting. This suggests light pollution reduced overall periphyton growth, a result that was actually opposite of what the researchers expected to find.

The experiment by day

Maja Grubisic, the Leibniz-Institute of Freshwater Ecology and Inland Fisheries

Grubisic noted in an interview that by using a lower intensity, her experiment mimicked real-life light pollution levels more commonly experienced by plant life. The low light intensities “may have been too low to boost photosynthetic production, but simultaneously disrupted other processes,” which may explain the unexpected lower growth found in the periphyton communities, she said.

ALAN on the grasslands

Light pollution has been shown to negatively impact much larger plants. In a four-year study of grassland plants, biogeographer Jonathan Bennie and colleagues from the University of Exeter found that, toward the end of the study, low intensities of LED lighting at night reduced the amount of one species, colonial bentgrass.

Grubisic said that light pollution may reduce some plant growth because of a “trade-off of effects" ALAN has on plants depending on its intensity. Higher levels of light pollution may indeed provide enough light to increase photosynthesis and plant growth. Whereas low levels of light may not provide enough energy to be stimulating but could disrupt other processes that depend on light as a signal, leading to negative consequences. Indeed, in the grassland study, whereas colonial bentgrass was negatively affected by low light, sweet vernal grass and Yorkshire fog grass actually increased under higher levels of light pollution.

Light pollution could be "disrupting" because light is also information for plants. If you live in a seasonal climate, you have likely witnessed this first-hand. As fall begins, the shorter days and cooler temperatures provide a signal to some trees that it is time to stop photosynthesizing and start dropping leaves to protect themselves from the impending freezing temperatures of winter. In fact, trees living near street lamps that had retained some of their leaves longer than normal was one of the earliest observations of the effects of light pollution on plants.

The experiment by night


In the case the periphyton communities, Grubisic suggested that the unnatural timing of light pollution could have disrupted the microscopic plants’ daily rhythm, depriving them of the much-needed rest and repair that occurs at night. But light in terms of energy can also be disruptive. Several types of microscopic plants found in the periphyton community can live under light intensities much lower than what was provided in the study. However, the amount of resources and energy it takes to maintain photosynthesis at night may cost more than the plant gains. In our interview, Grubisic said it is difficult to know whether one or both of these scenarios played out in her experiment, and that “exact mechanisms behind the effects we found remain to be determined.”

They did find that the results depended on how old the periphyton community was, as well as the season. The reduction of periphyton under light pollution only occurred in newly developing periphyton communities, not ones that were already established for 22 to 26 days (although a follow-up study using more sensitive technology found changes occurred in these older communities too).

A Joshua tree in California

Joshua Tree National Park

Light pollution also altered the makeup of the periphyton communities, but which species were most abundant varied by season. Further, in the spring it took three weeks for noticeable results, but only two weeks in the fall. These are important to consider in an urban an environment where physical disturbances like flooding, and chemical pollution such as agricultural run-off, could interact with light pollution to affect plants in complex ways.

Satellites have detected light pollution on every continent. Recent estimates suggest that 83 percent of the world’s population experiences some level of light pollution. This human-caused phenomenon is not isolated to urban areas, as light radiates out of cities to surrounding areas via sky glow. Despite increasing evidence that light pollution is effecting the world's vegetation, the number of direct field tests of light pollution on plants is low.

Moscow's light from space


Plants filter air and water, and they are also a source of food, medicine, and raw materials for humans and other animals. When light pollution negatively affects plants, it may impact these resources with far-reaching consequences. Still, there are ways individuals and communities can minimize light pollution impacts, Grubisic said. The use of motion-sensors, placing lights only where necessary for safety, such as busy street intersections, and utilizing designs that direct or focus light on specific locations, for example, can reduce total light pollution and minimize far-reaching glow. Less light pollution can help humans, plants, and creatures of all kinds keep a more natural rhythm.

Kylla Benes studies



]]> Fri, 29 Dec 2017 09:28:05 EST Shrews change size with the seasons. Could we do it too? The environmental case for smaller, more adaptive humans Jasmin Imran Alsous "Growing" means getting bigger, right? We start off small – as small as a single cell – and through very many cell divisions and adequate nutrition, grow bigger, until we reach adulthood. We may experience some weight gain over the holidays and some bone degeneration at old age, but the sizes of our adult bodies, much like those of most other vertebrates, remain fairly constant for the rest of our lives.

Not so in some mammals, it turns out. Specifically, not so in the common shrew (Sorex araneus), coincidentally Britain’s fourth most common mammal. These animals can "grow" smaller. Then bigger. Then perhaps smaller again. And they do it not through dieting or through water loss, but through palpable changes in the sizes of their bones, major organs, and overall body mass.

These cyclical changes in size are not random, but seasonal: shrews appear smaller in the frigid winters and plump up in the blossoming spring, a seemingly rare yet clearly effective survival strategy in the face of fluctuating environments and resources. And shrews aren't the only ones: weasels apparently do it too.


Courtesy of Javier Lazaro

More commonly known as the Dehnel phenomenon, these bewildering observations first caught the attentions of a Polish mammalogist, August (Gustaw) Dehnel, in the late 1940s. Since then, researchers have followed up on Dehnel’s work, collecting more data, searching for this phenomenon in other animals, and pursuing answers to the most elusive of questions – how?

Along the way, some have even asked if we humans could too co-opt this strategy - not to survive winters per se, but to survive future food shortages. In essence, could we, by getting smaller, reduce our carbon footprint and our pollution to save our planet? The debate has since been rife.

Despite garnering much interest, the Dehnel phenomenon has been challenging to study, methodologically speaking. In fact, up until now, these seasonally driven size changes had mostly been studied in skulls of dug-up shrews post-mortem.

The authors of a recent study however, all from the Max Planck Institute for Ornithology, set out to change that. Their goal was to witness these anatomic changes live: the ideal study would allow them to document changes in the skull size and body mass of individual shrews over time.

Shrew boxes

Courtesy of Javier Lazaro

To that end, the authors lured wild shrews in Moeggingen, Germany with mealworms, their absolute favorite. Armed with live-traps and an induction chamber commonly used for inhalation-anesthesia procedures, they managed to capture and temporarily knock out the wild animals.

While in deep sleep, the authors took measurements of the shrews' body masses as well as X-ray images of their braincases, the part of the skull that encloses and protects the brain and is the most commonly used proxy for skull size. The shrews were then marked with subcutaneous tags and released.

This methodology, repeated once a month, allowed the authors to document skull and body-size changes in wild shrews throughout the summer, winter and subsequent spring. But the real money was in the 12 shrews that fell for it each time. For each of these prized individuals, the researchers documented an entire lifetime of cyclical anatomic changes: summer peak, winter shrinkage, and spring regrowth. This data set was a definite step or two up from dead shrew remains.

Wonders of the shrew

The common shrew does not live too long by our standards: most are born in the early summer, and die after experiencing a single winter as sexually immature sub-adults, and another spring or summer as adults. Yet even in that limited lifespan, they accomplish several feats.

Behold, my first trick

Courtesy of Javier Lazaro

First, shrews exhibit the largest seasonal changes in skull size and body mass ever recorded in a mammal to date. Specifically, after months of luring, trapping, and measuring, the authors documented an average decrease of 15.3 percent in the height of the shrews’ braincases in the winter, followed by a spring recovery of 9.3 percent. The shrews’ body mass exhibited similar behavior, decreasing an average of 17.6 percent in the winter seasons followed by a whopping increase of 83.4 percent in the spring. 

Second, shrew pups move around by forming caravans: they get into in a single file by clasping on to the tail of the sibling in front of them with their mouths, with mama shrew leading the way. This doesn't have to do with their growth patterns, but it's still quite a unique achievement.

Researchers have postulated that shrews' remarkable adaptability to seasonal changes is a survival mechanism. Some animals migrate, hibernate, estivate, and some, like fat-tailed sheep, store fat in their booties. Shrews adapt the sizes of their bones and major organs.

In cold seasons, a smaller body allows these highly energetic animals to survive the relative food scarcity as their metabolic demands increase in frigid temperatures.

While, I imagine, most vertebrates stand to benefit from such a strategy, this is particularly advantageous in shrews and some mustelids, like weasels and badgers, who tend to have higher metabolisms than mammals of a similar size.

A subsequent increase in size in the warmer months corresponds with breeding season, when bigger bodies are likely to make males better competitors and females better pup-bearers.

A mysterious mechanism

While impressive, shrews are merely doing what shrews do: they are responding to predictable weather changes – ones for which they have evolved over very many years. Sudden and extreme environmental changes can thwart even the most prepared: how such animals will fare as environmental conditions take unexpected twists and turns is unclear. Even less clear is the nature of the mechanisms that allow for such variations in the sizes of bones and organs. This, to my mind, is the most interesting question about the Dehnel phenomenon.

The blue gloved shrew feeder

Courtesy of Javier Lazaro

The authors suggest that one obvious possibility is that bones are somehow broken down and resorbed into the body in the winter and restored when warm weather comes knocking. But the devil is in the details: how are these environmental changes communicated and signaled to the body at the cellular level? What makes some organs responsive to such stimuli, but not to others? How does the body generate ‘new material’ for bone recovery in warm seasons?

The role that genetics and the environment play in determining the nature of such changes is also unclear. While the seasonality of these anatomical alterations may be genetically encoded, the extent to which they occur may hinge on how extreme the weather changes are. Unraveling the intricacies of this particular example would add to the repertoire of known mechanisms that allow living things to take in external information and to respond to it adequately and in a timely manner – i.e. the mechanism that allows us to exist.

Medically and less existentially, elucidating the physiological and genetic regulation that underlies these flexible anatomical changes in juvenile or adult mammals can have profound implications for how we approach degenerative afflictions that target the skeleton and major organs. Imagine if we could regenerate bones in osteoporotic patients, or regenerate livers in cirrhotic individuals with the same reproducibility and ease.

What if, additionally, we could co-opt such ploys for our survival? In reality, it was only a matter of time before someone suggested we weasel ourselves into smaller bodies as well to solve our ballooning population problem and pending doom of food shortages.

After all, we are persistently contemplating our cities of tomorrow in all of their challenges and opportunities: the nature of our food supply networks, the expanse of our futuristically green architecture and the perhaps frightening pervasiveness of our technologies - so why not re-think the (wo)man of tomorrow?

Some definitely have, and at least two individuals think the (wo)man of tomorrow is a significantly smaller version of our current selves.

'Greener' humans

Arne Hendriks, a Dutch historian, and 6’4", appears to be at the forefront of such thought experiments and, in his project 'The Incredible Shrinking Man,' is suggesting we downsize ourselves down to a mere 50 cm, about the size of a baby. This, he calculates, would reduce our consumption of food and fuel to 2 percent of what it is now. It would significantly reduce pollution. It would also allow us all to fit into the first class cabins of trans-atlantic flights.

And he is not alone. Matthew Liao, a bioethicist from New York University, has been toying with the idea of shrinking future humans by about 15 cm: a "greener" human with a smaller carbon footprint. This may be a less humorous suggestion than Hendriks', but it is more imaginable, and while nightmarish (hundreds of genes are involved in height determination), perhaps even theoretically doable given current and advancing genetic screening technologies.

But what about our cognitive abilities? For it would be a sad irony if our intelligence masterminded our then-irreversible dumbing down.

This question has not escaped the attentions of the shrew article’s authors. In fact, in a subsequent study, they showed that while smaller brains reduce energetic requirements, they also did impinge on the animals’ cognitive abilities: in experiments that tasked the shrews with spatial learning tasks, summer juveniles and spring adults, both which have relatively larger brains than winter individuals, sampled smaller distances in their quest for food.

That doesn't necessarily mean that this would happen to us smaller humans. After all, there is an accidental precedent: The Dwarfs of Sindh, of the Sindh province of Pakistan, grow to be only about three feet tall. The cause of their short stature is a mutation that leads to severe growth hormone deficiency. In a newspaper clip from the 1990s, individuals did report being unable to till the land or partake in their ancestral occupation as a result of their diminished size, yet researchers found no intellectual deficits in this unique cluster of dwarfism.

And if that's not convincing, recent studies have also shown that our brains have indeed diminished in size over the past 20,000 to 30,000 years or so, losing the volume equivalent of a tennis ball. Yet here we are

Jasmin Imran Alsous studies

Chemical Engineering and Biological Engineering


Princeton University


]]> Wed, 20 Dec 2017 17:01:56 EST Tiny computers are transforming weather data collection Sometimes my job is to fly sensors on kites – for science Alison Nugent Imagine you're a farmer in a developing country, and not only do you have no way to measure the amount of rain you received this month or this year, but you also have zero knowledge of past trends. Outside of anecdotal knowledge, or what your neighbor or grandfather tells you, you're running a business blindly.



A remote weather station

Climate Station / Wikimedia


Handheld weather stations






More data > costly data


Sea salt at work

Rennett Stowe / Wikimedia




Flying for science


Hapuna beach

Polihale / Wikimedia





Alison Nugent studies

Atmospheric Science


University of Hawaii


]]> Mon, 18 Dec 2017 09:27:56 EST How fieldwork on a remote, tiny island taught me to navigate family dinners Doing science far away helped this ecologist talk to those close to home Jenny Howard I am headed home to Maine for the holidays, and I am beyond thrilled. I haven’t celebrated Christmas with my family since 2012, due to warm-weather fieldwork commitments on Johnston Atoll and the Galápagos Islands for my PhD research.

Even though I am excited to share in the magic of the snow, lights, and cookies, I am also a little bit nervous: I have different political views from my family, particularly my father, and in the past this has resulted in hurt, anger, and major frustration. I'm nervous that we will stumble upon a topic of conversation that is a trigger for me – if I believe something strongly enough, I take on an attitude akin to a verbal fight to the death. For me, these topics tend to be science-related – especially climate change – and that is a sensitive topic where my Dad and I disagree. It's a horrible irony to be a scientist broadly studying the effects of climate on seabirds while my dad is a climate skeptic.

For scientists and even general science supporters, the holidays can be a tricky time of year. It is that time when we are thrown head first into engaging with people that don't have the same opinions or political leanings. I get excited to talk about my research but hesitate more with my opinions where the science and policy intersect. With the current political environment, that could become a heated topic quicker than I could finish my eggnog.

There are sharp divisions between Democrats and Republicans in the US, and that divide continues to widen. It also carries over to climate change, more in focus than ever as we are the only country to reject the Paris Climate Accord. Given the alterations to websites for government agencies, like the EPA, regarding climate change, one can understand how climate change may be a sensitive topic for a Democrat to bring up in a Republican household. I also have prior experience to go on: political discussions that escalated during a Thanksgiving dinner in 2008 were less-than-positive (to say the least) for all present.

My strategy in my conversation with my Dad that year had been to try to win my argument by sharing knowledge. My dad grew up on a farm in rural Maine, attended the University of Maine, and is a very smart man. I returned home for Thanksgiving break, recently liberalized from university, thinking I was a smart woman. I was sure that when I presented him with my facts, he would think differently about climate change and come to realize that we humans have a direct role in it.

"Climate change is happening; studies have shown this," I told him heatedly, offended he thought otherwise. "CO2 has increased in the atmosphere. They expect the temperature to increase more than two degrees Celsius in the next century." Needless to say, this strategy wasn't effective. We fought, soured Thanksgiving for everyone, and politics were banned as a topic of conversation in our house.

This year, I return home equipped with some new skills. Through my experiences living and working with diverse groups of researchers on remote islands, I have learned that reiterating my opinions or knowledge about a subject will not help me win a persuasive argument. You can't get in an argument in that situation and then leave afterwards. If you fight with someone, you still see them for breakfast, lunch, and dinner. You hang out in free time and work time. You are each other’s friends, family, and colleagues. Living and working in these unique field environments required a better way to handle minor disagreements. And I would like to credit all the wonderful human beings I worked with on islands for helping show me what worked – or didn’t work – in difficult or sensitive conversations.

Here are some strategies – hard-earned life wisdom – that, when somebody asks a tough question or isn’t on the same page, you can have at the ready:

  • Know – really understand – your target audience. Facts and evidence do not seem to always convince people, so we need to understand our audience to try to reframe science in a new, digestible package. This requires you to be an active listener.
  • Know your own opinions and be confident in them. (Yes, I believe human-caused climate change is happening). But don't let your own opinions make you deaf to another opinion.
  • When confronted with someone opposing your view, take a deep breath before responding. Don't start with negating that person's view point or feeling (even though it may be tempting). Take another deep breath. Or use the opportunity to take a sip of water and nibble a holiday cookie.
  • Try using wording that really shows you want to converse with the individual, not lecture them. Try saying, "That is interesting. Why do you feel that way?" "Have you considered that...?" Or, "I hadn’t heard that information before; where did you learn that?”
  • Do be conscious of your tone and body posture. Using the same wording in two different ways can have completely different outcomes. Keep your tone light, make eye contact, and have a smile to show someone that you are open to conversation and listening. Crossing your arms, I have learned, makes you seem defensive and might inspire the same feelings in that person that you actually, really want to engage in conversation.
  • Be respectful.
  • Be ready to accept “rejection.” I try – and it is a process of trying – to remember to engage the curiosity inside another person. Even if I don’t persuade someone to think differently, maybe I still gave them a new nugget to ponder.

I present these ideas with the hope that it gives us all things to consider, and not as a cure-all for differences in opinions between people. For example, my dad will never be the environmentalist that I think he has the potential to become. It drives me nuts that he doesn't believe in climate change and recycles only because they have to pay per trash bag. And that he keeps buying small, disposable water bottles – the kind that holds maybe half-a-cup of water. But I think that over time, and with the right attitude, we can both learn something from one another.

Jenny Howard studies



Wake Forest University


]]> Fri, 15 Dec 2017 09:29:23 EST It's time to stop excluding people with disabilities from science You can be a great scientist without being able to carry a 50-pound backpack out of a cave Gabriela Serrato Marks As a kid, I loved to spend all day playing in dirt, digging holes at the beach, and adding pebbles to my rock collection. I turned that curiosity into a career in geoscience; now, I'm a full-time nerd, working on a PhD in marine geology. My field work involves hiking into caves, finding large stalagmites, and carrying them back out. Back in the lab, I saw them open and drill out powders to analyze their chemical ratios. I have really taken my childhood rock collection to the next level.



The young geochemist

Gabriela Serrato Marks




m01229 / Flickr




Gabriela Serrato Marks



Gabriela Serrato Marks



Gabriela Serrato Marks studies

Marine Geology


Massachusetts Institute of Technology


]]> Mon, 11 Dec 2017 17:05:39 EST Pollution and climate change hurt children most of all An ER doctor explains how these shifts compound childhood illness Renee Salas The environmental damage we cause by continuing to burn fossil fuels affects children most, including yours. While the studies on climate change are still emerging, there has been enough research to result in a broad scientific agreement that climate change is negatively affecting children’s health. In fact, one study estimated that about 88 percent of the disease from climate change afflicts children.

As an emergency medicine physician in Boston seeing these consequences, I have had a growing realization that my responsibility to protect my patients, especially vulnerable groups such as children, has to also include speaking up about the forces that impact them outside of the hospital.

Frederica P. Perera, a professor of environmental health sciences and director of the Columbia Center for Children’s Environmental Health, recently released a review article showing yet again how air pollution and climate change interact to multiply the negative health effects children face.

The truth is gravely startling. Ever since the industrial revolution, we've been dependent on fossil fuels to make energy. In 2011, 82 percent of our energy came from fossil fuels. Fossil fuels are largely coal and natural gas but also include diesel fuel, gasoline, and oil. A broad range of air pollutants are created when these are burned to produce electricity or heat or used in transportation and industry.

These pollutants include a laundry list reminiscent of chemistry class, including fine particulate matter, black carbon, polycyclic aromatic hydrocarbons, mercury, nitrogen dioxide, sulfur dioxide, carbon monoxide, sulfate, nitrates, and ozone. Combustion of fossil fuels also produces carbon dioxide, or CO2, which is the biggest driver of climate change.

A multiplier effect

The combination of air pollutants and warmer temperatures creates a perfect storm where they interact to multiply the effects that each would have alone. For example, Perera writes, the warmer environmental temperatures created by climate change causes the chemical reaction that forms ozone, an air pollutant with many negative health effects, to happen faster and more frequently. This increases ozone, which increases the negative health effects. Another example is that the concentration of small particles of pollutants increases as climate change alters temperature and precipitation cycles (i.e. floods and droughts) and creates stagnant air.

Part of the cycle

SMU Central University Libraries

People of all ages are exposed to this myriad of air pollutants in the changing climate, but children are more at risk of a wide spectrum of negative health effects because their developing bodies can suffer permanent damage from interference with their growth.

When children begin growing in the womb, they are especially susceptible to any factors that may alter the formation of their body. For example, a fetus develops nearly all of its 86 billion brain cells there. And cell development is very sensitive to exposures that may damage genes.

Once a child is born, the brain, lungs, and immune system aren’t fully formed until the age of six. Even their air and food exposure in proportion to their size is much higher than adults – the amount they eat in relation to their body weight is three to four times greater than that of adults. Young children also have no control over what they get exposed to – they must rely on their adult caretakers to keep them safe.

We all instinctually seem to recognize this vulnerability; there is a nearly universal core response to protect children from suffering. This is often the starting foundation that allows me to immediately bond with parents while on a shift in the emergency department. Any shift could provide examples, but there are always some encounters which remain with you.

One memorable couple was Megan and Rashad*. After entering the exam room, I found Megan resting her hand softly on her growing belly as her other hand tightly gripped that of her husband. Before she discussed the urination issue the triage note described, she sheepishly confessed that this was her first pregnancy and apologized if she was being overly cautious. After I provided reassurance, Rashad began to tell me how worried he was about her going out in these hot summer days.

“I know that we can’t protect our son from everything in this world, but we want to try to make it as perfect as possible while he is still in there,” he said as he gestured to his wife’s belly. He gave Megan’s hand a squeeze as they looked tenderly at one another.

He's not wrong to worry. When a fetus is exposed to air pollution, they are at increased risk of having a low and unhealthy birth weight, being smaller in size, or dying. Certain air pollutants have been found to affect the development of the brain and nervous system. Children also have an increased risk for being developmentally delayed, having lower intelligence scores, and less of a certain part of the brain called white matter, the stuff that helps you walk and talk. Their mental health is also at risk as children exposed to air pollution have higher rates of anxiety, depression, and difficulty paying attention.

Another unforgettable encounter was with Devon, a four-year-old boy with asthma who came to the ER with difficulty breathing. Devon’s mother was perched nervously at the end of her seat next to the oversized stretcher that seemed to dwarf her little boy. I made a funny face at him, and he smiled playfully despite having such labored breathing. The oxygen and medication in his face mask filled the room with a hissing noise as they tried to re-open his air tracts. I handed his mother a tissue as tears began to form in the corner of her eyes.

“He has so many of these breathing attacks now," she whispered. "This is his third this week. Something is changing. I am afraid to even let him go outside anymore."

Salt Lake City in smog

Eltiempo10 / Wikimedia

Young lungs are also at risk for wheezing as the increased CO2 in the air causes plants to produce more pollen. Air pollution can also cause serious issues; it has been found to reduce lung function even in children without a diagnosed lung disease like asthma. Researchers have found that children exposed to higher levels of air pollution earlier in life have reduced function at the age of 18, when the lungs are nearly mature, without an ability to recover; these children have reduced lung function for the rest of their life. Some research suggests that exposure to air pollution in the womb or early in life can actually cause asthma.

Climate change can also cause children to suffer from malnutrition and from infections. A 2014 study by environmental health scientist Samuel Myers at Harvard found that increased CO2 in the air causes crops to have less nutrition. This can have serious implications if food is already scarce. And children are more at risk for infectious disease due to factors such as immature immune systems. Since climate change is worsening malaria and diarrheal illnesses, children's' risk of contracting them keep growing.

As though these examples of the biological repercussions of air pollution and warming weren't enough, they are also causing more extreme weather, which can lead to children dying from physical trauma, like drowning. Globally each year between the years of 1990 and 2000, 66.5 million children were affected by extreme weather, and 600,000 died.

Society's toxic environment

It's impossible to research these effects using the standard experiment setup that includes groups experiencing different conditions, because that would require an unethical design, such as exposing one group of children to a known air pollutant and not another group and then measuring the incidence of the health outcome. Thus, in public health these association studies are enough for action, especially when one considers the precautionary principle. This states that when harm to other humans is plausible, actions should be taken to reduce it.

An example of one of these research studies cited in Perera’s paper was completed by C. Arden Pope III, an economist at Brigham Young University, in the late 1980s. Data on the health of the residents of the Utah Valley was collected from the time period before, during, and after a nearly three-year closure of a local steel mill. Since the steel mill was the primary source of pollution in that region, the amount of air pollution the citizens were exposed to was much lower during its closure. The findings showed very clear associations: more people suffered from the effects of air pollution when it was open.

Wildfire smoke over California in 2015


Meanwhile, back on shift, I check in on Devon to see if his breathing is improving with treatment. His mother smiles warmly as I enter, prying her eyes away from the TV screen. “Have you seen the news about these forest fires out west? I have never seen fires so bad,” she exclaims. Their frequency and intensity are worsening with the warmer temperatures of climate change and droughts that decrease soil moisture. The air pollution caused by these fires can travel far distances and affects everyone’s lungs. I shake my head as I imagine the havoc the fire pollution would cause on Devon’s lungs, which are still filled with high-pitched wheezes.

As I say goodbye to Rashad and Megan, Megan informs me that she had given up smoking a year ago in preparation for her pregnancy. I excitedly reinforce her decision as she reaches her right hand above her head to give me a high five. As I watch them walk towards the double doors, I sigh as I think of the all of the fossil fuel pollutants in the air that may in fact be worse than the cigarette smoke she so excitedly discarded for the sake of her unborn child. While they rightly want to do everything they can to create a perfect environment for their child, we as a society are creating a toxic one.

At the end of my shift, I myself pass through those double doors and into the muggy city air. I know that as long as the burning of fossil fuels spews forth more air pollution and climate change, I will continue to see exponentially more children suffering lung problems as parents' goal of creating a perfect environment for their child to develop in becomes more impossible to achieve. Instead, I will see more and more child illnesses from fossil fuel. It is the children in my life, as well as my patients, that spur me to action. Unless we make drastic changes now, this harm is unavoidable.

*Identifying details have been changed to protect patient privacy.

Renee Salas studies

Emergency Medicine


Massachusetts General Hospital and Harvard University


]]> Mon, 11 Dec 2017 09:24:40 EST Alaska's oilfield has been subtly changing the state's environment for decades. Will Congress notice? A new study reveals decades of cumulative change at an oilfield where caribou raise their young Julia York When I was a kid, I trapped ground squirrels using strips of carrot as bait. The squirrels lived in sandy burrows overlooking the Atigun River as it flowed out of northern Alaska toward the Arctic Ocean, and my dad studied how they overwintered there. We trapped the same squirrels over and over again – they love carrots. That allowed us to study them several summers in a row, and try to understand how an animal can spend eight months of the year underground, unconscious, their bodies approximately the temperature of ice water.


Caribou on the Colville River

Paxson Woelber / Flickr



The Alaskan North Slope oilfield 

Julia York




The tundra and Brooks Range mountains, Alaska

Julia York









Collapse and flooding alongside the road used for hauling

Julia York






Julia York



Julia York studies

Polar Science


University of Texas at Austin


]]> Thu, 07 Dec 2017 16:50:04 EST How Saharan dust can influence health all the way in Florida Bacterial blooms could cause disease in humans and coral Maite Ghazaleh Bucher Every so often in the Florida Keys, where coral reefs teem with marine life, an orange haze coats the sunset in the horizon – a fog of Saharan dust that wafts directly from Africa. 

The desert dust settles on the ocean and provides nutrients to tiny bacteria. Perhaps unfortunately, some bacteria use those nutrients to multiply exponentially, and in turn a subset of those bacteria might increase disease risk for beach-goers, divers, and fishermen alike.

Vibrio is a genus of bacteria that is ubiquitous in coastal environments where rivers meet the sea. Some species are pathogenic and, when ingested, can cause watery diarrhea, fever, and abdominal pain, also known as vibriosis. A different freshwater Vibrio, V. cholerae, is responsible for the ongoing cholera outbreak in Yemen - the epidemic is expected to affect one million people by the end of 2017. 


Bobtail squid

Wikimedia / Nick Hobgood


The atmospheric dust, traveling from the Saharan desert and pulsing into the Caribbean, serves as extra fuel for Vibrio. The dust contains nutrients – such as iron, nitrogen, and phosphorous – that bacteria use to multiply. A study, published last May in the Proceedings of the National Academy of Sciences, found that when these dust storms reach the Florida Keys, Vibrio bacteria exponentially increase in abundance within 24 hours. This may be due to Vibrio’s unique ability to rapidly respond to nutrient pulses more effectively than most other bacteria.

Miami bound



Westrich at work

Maite Ghazaleh Bucher

Then, Westrich and his colleagues set out clean collection bottles, petri plates with Vibrio-selective media, and filled the boat with gas – and they held their breath. As soon as the model signaled an incoming dust pulse, the team took off toward the haze to collect samples from Florida reef waters. With a lot of preparation and some luck, they collected data on three different occasions, July 2013, July 2014, and August 2014. On these occasions, they saw a surprising 30-fold increase in the number of Vibrio bacteria in the water column within 24 hours after the arrival of Saharan dust.


Bacterial blooms

Jason Westrich



Scientists at the University of Georgia, such as Erin Lipp and myself, are also investigating the relationship between these dust storms and diseases for nonhumans, especially corals. The complex structure of coral reefs are created by animals called corals, which form large calcium-carbonate skeletons. Reefs form natural fisheries that create jobs for fishermen and the tourist industry. Reefs also shield shorelines from storms and changing seas, by serving as natural breakers that slow waves and prevent erosion. 

Vibrio in miniature

Randy Ramsey



You can support a healthier planet by eating more plant-based meals, walking to work, speaking up during local elections and buying local foods. With these simple tasks – a lot of preparation and maybe some luck – we can, perhaps, collectively tame the dust storms that cause Vibrio blooms.

Maite Ghazaleh Bucher studies

Environmental Health


University of Georgia


]]> Wed, 06 Dec 2017 17:09:44 EST The most cost-effective ways to fight climate change are literally under our feet A new study says forests, swamps, and soil are the cheapest ways to help save the planet Jane Zelikova In 2015, most of the world came together in a rare act of collaboration and set an ambitious goal to limit global temperatures from rising no more than 2°C. Each country, from China to Belgium to Peru, outlined a path to best reduce emissions, according to their people, geography, and economy. The US has declared its intent to exit the agreement, but so far hesitated, and many states plan to find their own solutions independently. Their options include low cost, natural mitigation plans that do not any require major technological breakthroughs. 

These plans have become all the more appealing in the wake of a recent paper that breaks down the latest and most successful natural climate solutions, from growing trees to harnessing the power of soils. If implemented between today and 2030, the methods could remove more than a third of the atmospheric carbon we need to reach our climate goals in a cost-effective way.

To state the conclusion upfront: nature can help us limit global warming to 2°C, through conservation, better land management, and restoration of ecosystems. And we can do it at a lower cost than most other solutions. 

The researchers, led by Bronson Griscom and his colleagues at The Nature Conservancy, found that nations can get the most bang for their buck by concentrating on reforestation and limiting deforestation, in the US and across the world. Additionally, nations, states, and cities have many opportunities to store carbon in agricultural soils.

To assess these natural solutions and their potential effectiveness, Griscom and colleagues carried out an analysis of most of the world's current, land-based climate mitigation solutions. The project, the most comprehensive of its kind to date, is truly an effort built on the shoulders of giants, bringing together data from the latest scientific studies and climate models. 

The Nature Conservancy

Rather than testing specific hypotheses or asking research questions, Griscom and colleagues assessed 20 discrete climate mitigation options within the land sector, strategies like conserving forests, restoring wetlands, and planting cover crops. Their assessment fills in previous knowledge gaps, taking into account the need to safeguard food, continue fiber production, and protect biological diversity.

Nor did they ignore economic realities. To appropriately constrain their model by real-world demands, the authors estimated the potential mitigation plans using two cost estimates for removing carbon from the atmosphere, using dollars and megagrams, or the equivalent of just over a ton. The high estimate is $100 per about a ton of CO2 equivalent, and the low $10 per ton of CO2 equivalent. 

Accounting for these costs, the authors then created global maps of where to implement the 10 most promising solutions. Most notably, the authors provide a global dataset of reforestation opportunities, and how they are constrained by food security and biodiversity safeguards. This dataset can help countries target their efforts to where they will have the most positive impact.

Forests, soil, grasslands, and swamps 

We can start with what we know: Trees remove a lot of carbon from the atmosphere through the process of photosynthesis, nature’s way of turning waste into value. When trees grow, they use carbon from the atmosphere to build tree trunks, branches, and roots, locking away carbon molecules in solid form. The more trees we grow, the more carbon we remove from the atmosphere, so it should come as no surprise that the cheapest, most effective natural climate solution is reforestation.

Not to scale

Madhurjya Borah / Wikimedia

In fact, natural climate solutions that include reforestation, managing forests better, and soil conservation practices, can provide up to 37 percent of the needed carbon removal between now and 2030, an absolute must to reach ambitious climate goals. And natural climate solutions can deliver these climate benefits at a low cost: a third of them cost at or below $10 per ton CO2. 

That’s substantially lower than the estimated social cost of carbon, essentially the potential cost of dealing with carbon emission impacts, from health to environmental and economic (approximately $30 per ton of CO2 emitted). And most natural climate solutions deliver other benefits, including flood mitigation, water filtration, enhancing soil health and productivity, fostering biodiversity, and enhancing the resilience of natural systems. Not bad for $10 per ton CO2.

Other low-cost options for climate mitigation include restoring grasslands, reducing fertilizer usage on farms, and planting legumes that can make their own fertilizer (called nitrogen fixers). Another option is to plant trees into places with little agriculture, which has the added benefit of improving air and water quality and providing habitat for birds. 

With farming, it all comes down to soil: any practices that improve soil health rebound to the climate, because soils store a lot of carbon. Adding materials like biochar to soil could create a lot of mitigation potential, though that has yet to be well-demonstrated beyond research settings. We could also improve livestock practices; shifting grazing, feed supplies, and when herds move across the landscape could increase soil carbon and reduce methane emissions.

'Let's trap carbon!'

Public domain

Wetlands are not nearly as extensive as forests and grasslands, but they hold a lot of carbon, and they filter and clean water, helping build more climate resilience. Preserving wetlands is less expensive than restoring them, but both their conservation and restoration offer excellent and relatively low-cost opportunities for climate mitigation.

The authors also included new research results that report the potential to store carbon in soils, through agriculture practices that do not till the soils and methods of livestock grazing that promote healthy soils. These two practices have traditionally been excluded from global analyses of this scale but are important in agriculture. The authors also applied what's called "the Delphi method" of expert counsel, asking 20 experts to give their opinions – essentially “phoning a friend” or crowdsourcing to ensure their methods made sense in the real world, and not just in a mathematical model.

This new paper stands apart from others in that its authors combined several factors in their analysis, including cost and real-world feasibility, meaning their results highlight cost-effective solutions. It also takes into account food production and gauges solutions to minimize negative consequences. 

Nor is the paper only about mitigating climate change. The team, although searching for solutions, do not minimize the enormity of our challenge; the authors treat readers as adults who can face climate change honestly and move forward with concrete solutions.

Understandably, Griscom and colleagues were not able to account for potential breakthroughs in technology or industry, like the widespread adoption of perennial crops, like Kernza, instead of farming annual crops. The options examined by Griscom's team are by no means the only ones we have to choose from, but the authors have laid out a robust menu of options for how nations, states, and cities can enlist ecosystems as solutions to climate change. 

The largest question that the researchers did not address, even with a clear set of low-cost, currently available solutions, is how we might enact these projects. That "how" is critical, especially since there are often many different paths to the same outcome. The new paper gives us targets, but does not provide a guide to action. Ultimately, the onus falls on us to choose our paths of addressing climate change. Land stewardship is not a bad place to start.

Jane Zelikova studies



University of Wyoming


]]> Tue, 05 Dec 2017 17:30:31 EST What ancient corn farmers can teach us about engineering crops for climate change In the era of GMO crops, farmers can learn old lessons of diversity Gabriela Serrato Marks There are more than 50 strains of maize, called landraces, grown in Mexico. A landrace is similar to a dog breed: Corgis and Huskies are both dogs, but they were bred to have different traits. Maize domestication worked the same way.


If you think this sounds like an early version of genetic engineering, you'd be correct. But nowadays, modern agriculture is moving away from locally adapted strains and traditional farming techniques and toward active gene manipulation. The goal of both traditional landrace development and modern genetic modification has been to create productive, valuable crops, so these two techniques are not necessarily at odds.

Corn cob DNA

Jason Wallace / Wikimedia


From weed to tortilla




Domesticating maize

John Doebley, University of Wisconsin Madison




Young Maya Corn God

The Met



Crucial diversity


Flickr/Jay Galvin




Gabriela Serrato Marks studies

Marine Geology


Massachusetts Institute of Technology


]]> Mon, 04 Dec 2017 17:35:44 EST Can Hawaii's waterfall-climbing fish survive when mountain rains change? O'opu make extreme treks to breed that depend on stable climate conditions A bunch of goofy looking fish are trying to climb a waterfall using mountain climbing gear. Alison Nugent Here in Hawaii, not only are there rainbow sightings daily and dramatic mountain vistas obscured by clouds: we even have fish that can climb waterfalls. All these natural wonders are related to the way mountains influence rain patterns, and they could all be at risk thanks to human-induced climate changes.

The waterfall-climbing fish in Hawaii are called Oʻopu. Five species of Oʻopu live in Hawaii, but one, Oʻopu alamoʻo, are the best climbers. They're just a few inches long, hatch in high-altitude freshwater streams, and are washed downstream to the ocean. After three to six months, they swim back to the streams to breed, much like salmon. While both Oʻopu and salmon trek upstream, Oʻopu have a bigger challenge: the streams in Hawaii often have vertical rock faces. Luckily Oʻopu have grown pelvic fins that suction onto wet rock faces behind waterfalls, and they climb vertically upward, inch by inch. Oʻopu alamoʻo have been found as much as 422 feet up waterfalls.

Oʻopu are important to Hawaiian history and culture. The species has been both a source of food for and part of religious ceremonies by the native Hawaiians. Four of the five species of Oʻopu are found nowhere else in the world. They are also the only species of freshwater fish native to Hawaii.

Chasing waterfalls

But increasing human populations in Hawaii are threatening the Oʻopu stream habitat – and they need to be managed and studied to protect their livelihood.

Streams are sometimes rerouted or channeled to protect human property against flooding or for crop irrigation, both of which reduce streamflow.

Furthermore, Hawaii has seen an overall decline in rainfall over the last 30 years, and future projections show a continued decrease. The rock face needs to be wet for Oʻopu to climb, so the characteristics of the stream are important. The ideal stream conditions include steady flowing water over long time scales. Previous observation has suggested that the flash floods induced by heavy precipitation in Hawaiian streams could serve as a vital signal for larvae and juvenile Oʻopu in the coastal ocean to migrate back upstream. Flash floods may be OK for Oʻopu, but as you can imagine, droughts and dry rocks are not.

The fact that Oʻopu evolved to climb waterfalls tells us that the Hawaiian islands must have had steady precipitation patterns for hundreds of thousands, if not millions, of years. That type of skill doesn't appear overnight.

Most of the rain on the Hawaiian islands comes from a process called orographic precipitation. Orographic means "relating to mountains," so orographic precipitation is rain that is induced, or modified in some way, by the presence of a mountain. In the case of Hawaii, most of the orographic precipitation on the island comes from the incoming wind being lifted by the mountainous islands. This makes the mountains extremely important to the water cycle. To put this into context, the ocean area around the islands get an average of 25 inches of rain per year, while the mountains on the islands get up to 16 times that amount.

Of course, none of this would happen without clouds. They're composed of an uncountable number of tiny water droplets – so tiny that it takes about a million cloud droplets to make up a single raindrop.

Sticking to falls

Flickr/Austin McGee

Clouds form when air becomes saturated and can't hold any more water vapor. Reaching saturation usually involves a two-step process: first, air is lifted to a higher elevation where the air pressure is lower. Then, as the air pressure decreases, volume increases, so the air temperature drops. Just as dew forms on the outside of your cold lemonade on a hot summer day, cloud water condenses in the atmosphere as the air cools.

The mountainous terrain of the Hawaiian islands lifts air to saturation and forms clouds. The cloud droplets then collide together and collect each other to form rain drops, which fall onto the mountain tops, providing the water for the streams and waterfalls that Oʻopu climb. The process of orographic precipitation on the islands is reliable and continuous, day and night, summer and winter, and year after year.


Still, orographic precipitation cannot be taken for granted. My research has shown that the complex cloud processes responsible for orographic precipitation over islands in the tropics are sensitive to the wind speed. This is important for Hawaiian rainfall, because the decrease in precipitation over the last 30 years has been tied to a decrease in the trade-wind strength. Furthermore, tiny particulates in the atmosphere called aerosols can also affect orographic precipitation. Aerosols are ubiquitous in the atmosphere, from both natural and human sources, and the impact of aerosols on clouds in the atmosphere is the cause of one of the largest uncertainties in future climate projections.

All of Earth's processes are related. Changes to Earth's climate affect the atmosphere, including processes which drive rainfall, which affect streamflow, which affects stream species and their habitats. All of these shifts demand our attention in order to ensure that O'opu will continue to thrive far into the future.

Alison Nugent studies

Atmospheric Science


University of Hawaii


]]> Mon, 04 Dec 2017 10:15:12 EST Can termites teach us to build environmentally friendly communities? Meet the researchers searching for more climate-friendly architecture Salmaan Craig They each stood four Burj Khalifas tall, contained a population the size of San Francisco, and plugged into a network of tunnels sweeping the face of the planet. Any bug-boffin would recognize these giant towers, which formed the backdrop to Robert Silverman's dystopian novel The World Inside, as termite mounds scaled up to human dimensions.




Where's the cyclist?

Hunter King




Instinctual construction



A termite minion

Hunter King



Demystifying termite HVAC



A termite castle

Hunter King




Probes and rampaging termites










Conundrum solved




A school bus waiting for termite children

Hunter King





A model with potential






Salmaan Craig studies

Architecture and Thermal Engineering


Harvard University and McGill University


]]> Thu, 30 Nov 2017 19:39:49 EST Boobies of the Galápagos are replacing their disappearing food source with junk fish Decades of research show how the sardine's decline threatens an entire ecosystem Jenny Howard No hot shower? Sleeping in a tent on the ground? No fresh veggies, alcohol, or even – gasp – ice cream, for three months straight? For some, this might sound miserable. But in 2011, I eagerly jumped at the opportunity to live with four other biologists on an uninhabited island in the Galápagos Archipelago off Ecuador, all for the sake of studying boobies. Nazca boobies, that is: a brilliant white seabird with black wing tips and a salmon-colored bill that forages for fish hundreds of kilometers over the Pacific Ocean.

Like many species in the Galápagos Islands, Nazca boobies have a certain naiveté, or “tameness,” to humans – they don't leave the nest or respond to disturbance as many other bird species might. This has allowed researchers at Wake Forest University to track the same individuals over many years, some across their entire lifespan, without having negative effects on the individual or the population. Requiring incredible dedication and planning, the long-term project studying Nazca boobies on Isla Española, Galápagos, just entered its 35th year. Only through this long-term approach were scientists able to detect that climate change could cause a stable seabird population to decline.

Booby are what booby eat

A study published in August 2017 was the culmination of over 30 years of data from many field assistants, graduate students, and project leader, behavioral ecologist David J. Anderson (I'm now a PhD candidate in his lab). Dave has collected diet samples from Nazca boobies at Punta Cevallos, Isla Española since he started his PhD research there in 1983. A diet sample from a booby consists of dead fish that have yet to be digested, allowing us to weigh the sample, count the number of fish, and identify the species. Bonus: the bird that donates a diet sample will happily eat its fish back.

Before 1997, birds would return with large loads of one specific prey item, Pacific sardines, and regurgitate as soon as "you would pick them [the birds] up," because they were so full of food, Dave reports. But after the 1997 breeding season, he noticed that the birds returned with emptier stomachs, regurgitated less readily, and no longer returned with sardines. Sardines were replaced with flying fish that are less nutritious (like us substituting a bag of chips for a salad). What effect was this huge shift having on their survival and breeding? By studying the same individuals within the same population over time, he could observe it all happening.

Now sold in salt and vinegar

Public domain

One of the biggest challenges to answering a question on survival and breeding is time. When the diet first shifted from sardines to flying fish, and the relative number of birds returning with full stomachs decreased, the researchers didn't have enough data yet to answer whether the change had a significant effect on an individual's survival or breeding success. So they collected more data and waited for more years to pass.

In the meantime, data collection occurred primarily in the field, including daily monitoring of Nazca booby nests where sleeping in a tent, bathing in the ocean, and getting pooped on daily by birds was the norm. The colony, where the Nazca boobies nest on the ground, was just a three-minute walk from our campsite near the beach. Each day on the island, I headed into the colony at the crack of dawn, armed with a field notebook, pencils, and my most important tool: a soft plastic "booby stick," kind of like a chew-toy for birds.

Whatever, human

Jenny Howard

A booby stick distracts a curious, nibbling bird while I read the unique five-digit number engraved into a metal band on the bird's leg, or gently lift a bird to see how many eggs it may be incubating. Trust me, it is best to avoid that bill chomping down on hands or fingers. Boobies bite. Hard.

In my notebook, I recorded the band number, the number of eggs in the nest, and the sex of the bird (males whistle, whereas a female will honk). Finished, I walk to the next nest and began the same process. Over the course of a season (one breeding year), we monitor daily more than 2,000 nests to collect information on the parents, egg lay date, hatch date, and if the chick survives. These data feed into a large long-term database on breeding behavior by Nazca boobies, providing details on which years an individual bird breeds and, if it does breed, whether or not it raises a chick successfully.

Floundering off flying fish

Emily M. Tompkins, PhD candidate, first author on the paper, and my lab colleague, emphasized that these long-term studies are incredibly "valuable because they give us time to understand how animals respond to environmental variation.” She used statistical models to calculate the effect of diet on Nazca booby reproductive success and survival. Her analyses incorporated thousands of uniquely banded birds, 1,345 systematic diet samples, and nearly 34,000 breeding records across multiple decades, an amazingly impressive data set in a natural population.

Kingdom of the boobies

Jenny Howard

The main finding: breeding success under the flying fish diet halved. After 1997, sardines weren’t present in the archipelago, and Nazca boobies were forced to forage primarily on flying fish. As a result, fewer chicks survived, meaning that fewer adults will be at the colony to breed in the future.

Nazca boobies are currently considered a "least concern" species with a stable population in the Galápagos Archipelago and on Malpelo Island, Colombia. But with climate change warming the oceans – the waters where Nazca boobies breed are predicted to warm about 8°F in the next 100 years – and sardines unable to live and breed in warmer waters, Nazcas will continue to rely on flying fish as their main food source and the population at our Punta Cevallos colony on Isla Española could decline in the future.

Further studies on the large Nazca booby population at Isla Malpelo could help us predict whether the species can survive sardines' absence at that oceanic island, where the waters are also predicted to warm and be unsuitable for sardines. Regardless of what may happen at Isla Malpelo, reducing the Nazca booby population to one oceanic island would be a significant change in conservation status for this species.


Biodiversity Heritage Library

This research has further ramifications for other Galápagos species that are dependent on the same food source as the Nazca boobies. The blue-footed booby, a sister species of the Nazca booby, is an iconic species for the Galápagos, attracting world-wide attention and support. An earlier study published by the same group in 2014 demonstrated that the blue-footed booby population in the Galápagos had declined by greater than 50 percent since the 1960s. This decline seemed connected to poor breeding that began in 1998 as a result of their primary prey, also sardines, disappearing throughout most of the Galápagos Archipelago.

As the recent Nazca booby paper points out, if sardines are not able to inhabit the Galápagos Archipelago with future warming oceans, the already declining blue-footed booby population may be in trouble in the long-term.

Ripples through the system

Galápagos sea lions, the playful animals that fascinate tourists to the Galápagos are adept hunters that eat a diversity of food items, but they prefer to eat sardines. Like the blue-footed and Nazca boobies, the sea lions, too, could be threatened with a declining population in the future because sardines may no longer be able to survive in the warming ocean off the Galápagos Archipelago. Galápagos sea lions are endemic to the archipelago; if their population blinks out, that predator will be gone because no oceanic island is close enough (and further north) for relocation to cooler waters.

Island boss

Brian Gratwicke

While we are familiar with polar bears disappearing with melting sea ice, the Nazca booby is a critical reminder that tropical marine species may also be negatively affected by climate change. The loss of sardines from the diet of Nazca boobies, blue-footed boobies, and Galápagos sea lions could have large implications for other species farther down the food chain. Additionally, Galapagos tourism is driven by the desire and ability to see these beautiful species; climate change reducing their populations could have downstream effects on the tourism industry so vital to the country of Ecuador. As in long-term research, only time will tell.

Jenny Howard studies



Wake Forest University


]]> Thu, 16 Nov 2017 17:00:05 EST Life is evolving through a hurricane of human pollution Animals are adapting to pollutants in surprising and often costly ways Brittney Borowiec No other species pollutes the way humans do. Many pollutants, like dioxins, phenyls, hydrocarbons, and some pesticides, are so slow to degrade that they can persist for generations in an environment. Others, like the caffeine and birth control hormones we flush down the toilet daily, are released so constantly that they are replaced as rapidly as they are broken down.

Animals are doing their best to weather this hurricane that humanity is wreaking on the natural world. Some, like pigeons and rats, seem to thrive in new urban environments. Others, like coral reefs and giant pandas, seem to be dangerously close to extinction.

Animals that are best able to cope with human-caused climate shifts tend to be the ones to pass on their genes to the next generation. In this way, these selective pressures are the rules by which the “winners” and “losers” are decided, and influence the building blocks (genes) of evolution in a species. We don't know for certain how this will play out in animal populations around the world, but one place scientists are looking for clues is within lineages that have survived for a long time already in difficult environments, both natural and human-induced.

They have found that animals can adapt to polluted environments, and persist even in environments that are inhospitable to most living things, but that those changes cause evolutionary trade-offs. The ideal solution for one problem (like pollution) can lead to terrible consequences in another process (like reproductive success). This means that even if animals are able to initially survive in pollute environments, they'll still have to contend with long-term consequences that are difficult to predict, and could ultimately lead to their decline. And species that are able to escape extinction, and even thrive, like urban rats, are going to be drastically different from ancestors that evolved without human influence.

Adapting at a cost

Last month, researchers from Kansas State University and Juárez Autonomous University of Tabasco, in Mexico, reinforced this finding by examining how life in a toxic spring shaped the multiple independent evolutionary lineages at the site.

The Poecilia mexicana species complex is composed of multiple independent lineages of fish that have colonized toxic, hydrogen sulfide-rich springs occurring naturally in river drainages in southern Mexico. Fish from sulfuric springs show a suite of behavioral, physiological, and anatomical differences from populations in nearby, non-sulfuric springs. While the hydrogen sulfide in these springs is the product of a nearby volcano, it can also make its way into the aquatic environment from petroleum refineries, paper mills, and sewage.

Because the populations in sulfuric and non-sulfuric springs are isolated from each other and have continued on their evolutionary trajectories independently for some time, they form a fascinating natural laboratory that scientists can use to ask questions about how animals adapt to extreme environments.

Hydrogen sulfide is a respiratory toxicant – it shorts out mitochondria (“the powerhouse of the cell”) and makes energy production slow and inefficient. This is exacerbated by the fact that it takes a lot of energy – dedicated proteins and metabolic processes – to detoxify hydrogen sulfide to reasonable levels. Contributing to this chronic energy shortage is that few lifeforms can survive in the extreme conditions of the springs, meaning that food for predators like fish is limited.

Given this energy shortage at multiple levels of biology, the researchers hypothesized that perhaps populations from hydrogen sulfide-contaminated springs adapted to have lower energetic demands than fish from uncontaminated waters. By saving energy on routine maintenance, they reasoned, the fish would be able to allocate more of their limited energy stores to non-survival functions like reproduction.

Sultan of sulfur

University of Washington/Public domain

The team surveyed the body size and routine metabolic rate, two indicators of whole-animal energy demands, of Poecilia fishes from 11 field sites (five sulfuric and six non-sulfuric). They also reared fish from a subset of sites in the lab and conducted the same analyses. This extra step allowed them to track down whether any differences observed between the populations had a genetic basis (since they would remain even after the fish were raised in the same environment).

In support of their hypothesis, fish from sulfurous springs showed evidence of adaptation for lower energetic demands - they were smaller, and had lower oxygen consumption rates than fish from uncontaminated sites, even when reared in the lab. Though some river drainages showed more pronounced differences between sulfuric and non-sulfuric populations, there appeared to be convergent evolution for lower energetic demands in the Poecilia fishes, as multiple, distantly related, independent lineages appeared to find the same solution to the problem of life in a toxic spring.

Life in toxic soup

Like the fish confined to hydrogen sulfide-rich springs, killifish from a number of polluted sites have made similar adjustments in their physiology to adapt to their extreme environment. The species, which holds a special place in my heart, are renowned for their remarkable tolerance of a wide swath of environmental challenges including low oxygen, high salinity, large swings in temperature, and even the microgravity of space. They also have a reputation for being one of the few species that will doggedly persist in sites besieged by contamination, and have been the subject of intensive toxicological research.

Not so natural habitat


This all makes them a model ripe for examining how animals are rapidly adapting to our increasingly polluted world, and intensive study of the genetics and physiology of killifish populations residing in densely populated, urban estuaries on the Atlantic coast has taught us a lot about the population-level effects of pollution.

Compared to animals from clean sites, killifish from polluted areas are far more tolerant of a large class of persistent, toxic compounds like polyaromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCBs), and dioxins. And in spite of huge site-to-site variation in the exact nature of the toxic soup, the fish all seem to have the same basic adaption: desensitization of the aryl-hydrocarbon receptor pathway, an important detoxifying pathway that allows proteins to break down the toxic compounds that would otherwise harm them.

But why shut down a cellular response that helps to break down pollutants? The working theory is that desensitizing that pathway avoids its over-activation in contaminated sites, which can disrupt normal cell processes and lead to cell death. More focused work on specific populations has shown that these changes evolved quickly, repeatedly, and independently.

Conceptually, the sulfur-rich springs of southern Mexico are not all that different from a polluted killifish environment or a highly contaminated superfund site, where animals are persistently exposed to a cocktail of nasty urban and industrial chemical by-products. As animals come to grips with the new reality of life on Earth with humans, evolution marches on, as has been the case for thousands and thousands of lineages over millions of years. Only now, it's a race to adapt to what we're doing to the planet.

Humans are the world's greatest evolutionary force. How will animals cope with the new reality of polluted habitats? We can look at lineages that have survived for a long time in difficult environments (both natural and human-induced) for clues.

Brittney Borowiec studies

Comparative Physiology


McMaster University


]]> Mon, 06 Nov 2017 09:28:57 EST Only eight hurricanes hit New England in 100 years. Soon more will head for Boston Climate change is shifting storm paths, and new targets are underprepared Michael Graw Scientists have been sounding the alarm for over a decade that climate change is bad news for anyone who lives in the path of hurricanes. With the destruction wrought by Hurricanes Harvey, Irma, and Maria just this past summer, the connection between climate change and hurricanes has become hard for anyone to ignore.

Hurricanes are becoming more frequent, and the season is lasting longer each year. With an increasingly warm ocean, hurricanes can spin with more devastating energy and carry more moisture to flood coastal cities.

Amid all this, a new study, led by climate scientists Andra Garner from Rutgers University and David Pollard from Pennsylvania State, found that climate change might be having an additional, unexpected effect on hurricanes: they're moving north, bound increasingly often for northern New England rather than the mid-Atlantic states. Hurricanes are on the move, and they’re headed for Boston.

Garner and Pollards’ team set out with the intention of finding out just how frequently New York City will flood in the future. In the five years since Superstorm Sandy devastated the area, several studies have looked at how intensifying hurricanes and rising sea levels may effect the US’s most populous city. One such study found that, by 2100, formerly 100-year floods may occur as often as every three years. But that finding comes with a major assumption: that hurricanes in the future will hit New York City at the same frequency that they currently do.

New Jersey after Sandy

Flickr/US Air Force/National Guard

Rather than make any similar assumptions, Garner and Pollard created their model from the ground up. Using a combination of global climate change projections, hurricane tracking forecasts, and sea level rise models, they simulated nearly 300 years’ worth of Atlantic hurricanes through a warming climate and rising seas. New York, they found, would experience a 500-year flood every five years by 2300. But it wouldn't be because of hurricanes; those were missing New York, passing by to the east on their way to New England.

The modeled hurricane tracks, skirting New York and the rest of the mid-Atlantic states before making landfall in Connecticut, Massachusetts, and Maine, were puzzling. Hurricanes that turn north of the Caribbean should eventually be forced to make landfall in the mid-Atlantic by an area of high pressure that sits just offshore. Only eight hurricanes in the last century have made landfall on the New England coast.

But thanks to climate change, that high-pressure zone may be weakening. A research team led by the National Oceanic and Atmospheric Administration looked at tropical storm tracks around the globe for the past 30 years, finding that tropical storms have slowly been shifting poleward in their respective hemispheres. This suggests that climate change is disrupting the balance of atmospheric pressure between land and ocean. This side effect of climate change was first pointed out in 2003, but the mechanism behind it continues to baffle scientists – and as a result, it mostly isn’t accounted for in hurricane models.

Garner and Pollard’s ground-up approach appears to have captured this global shift, however. And with the high pressure ridge off the US’s east coast expected to continue diminishing over the coming centuries, there’s no atmospheric nudge pushing hurricanes onshore before they intersect the New England coastline as it juts out into the Atlantic.

That’s bad news for New England – but it’s hard to say exactly how bad. That coastal communities in Connecticut, Rhode Island, Massachusetts, New Hampshire, and Maine are at risk of inundation from sea level rise comes as no surprise, but no one has looked at how hurricanes might amplify flooding in Boston in the same way that Garner and Pollock sought to do for New York.

In fact, one study that attempted to map the combined effects of sea level rise and hurricanes for the entire US East and Gulf coasts actually set the northern limit of their analysis at Connecticut. So where New York City planners are now equipped with estimates for maximum storm-induced flood heights, their counterparts in Boston – which now appears to be at an increased risk for hurricanes – are relying on underestimates based on sea level rise alone.

The historical rarity of hurricane landfalls has also left the region relatively unprepared for a major storm. For example, Massachusetts’ building standards only require homes within one mile of the coast to withstand 110 mph winds (the upper limit of a Category 2 hurricane) compared to 185 mph in parts of Florida. Moreover, that Massachusetts law exempts all homes constructed prior to 2009 – in a region famous for its historic coastal communities. In addition, huge swaths of Boston and eastern New England are low-lying coastal plain similar to Houston - by 2100, as much as $85 billion in property is anticipated to lie in Boston's 100-year floodplain.

The consequences of unpreparedness are hinted at by the beating New England took from storms earlier this decade. Irene, no longer a hurricane when it passed through the region in 2011, caused more than $700 million in damage in Vermont alone as normally placid creeks swelled to overtake entire towns. Six years later, residents there are still working to rebuild. The following year, Sandy infamously ravaged the Connecticut coastline and caused $360 million in damages. With the effects of potential future storms amplified by sea level rise and even higher wind speeds, that destruction could increase sharply from the next major storm.

The upside is that Garner and Pollards’ study, combined with the spotlight on hurricane preparedness shone by the historically bad 2017 hurricane season, may be the warning New England communities need to prepare and adapt. The same modeling approaches applied to New York to determine flood heights and frequencies can be used to update Boston’s inundation maps, and Houston’s tragedy may serve as a lesson other to cities about the unexpected risks they face from storms.

Climate change is changing everything about hurricanes, including their trajectories – and New England needs to prepare for a wet future.

Michael Graw studies



Oregon State University


]]> Thu, 12 Oct 2017 09:35:26 EST Biodiversity doesn't just arise out of healthy ecosystems. It helps create them Why researchers are starting to think differently about biodiversity Cassie Freund The human race is currently conducting the largest-scale biodiversity removal experiment to date. By stripping tropical and temperate forests of trees, fishing out the tastiest animals from our oceans and rivers, and pumping carbon dioxide into the atmosphere at unprecedented rates, we are driving species – both popular, charismatic animals like the polar bear, as well as less beloved but potentially crucial plants, insects, and microorganisms – toward extinction at a rapid clip.



Tail wagging the dog?








Real-world evidence



The Manaus rainforest in Brazil

Phillip P. Haris




Cassie Freund studies



Wake Forest University


]]> Tue, 10 Oct 2017 07:33:06 EST We know how to fight wildfires effectively. Why don't we do it? Prescribed burns lessen the damage, but the risk repels lawmakers Michael Graw The West is burning. A spate of wildfires in California killed 10 people on Monday, in addition to the 8.5 million acres of the western United States that had already been set ablaze by late September. It's the third-worst season on record. 

Thousands of people have lost their homes to the flames, and cities across Montana and Idaho were so blanketed in smoke at times that residents were warned the air was unbreathable. In all, more than 30,000 firefighters have been dispatched to the front lines to stem the blazes.

The price tag for all this? More than $2 billion. And that’s just to contain the fires. Accounting for infrastructure damage and insurance payouts, this fire season will leave taxpayers with a bill likely to top $30 billion.

Meanwhile, wildfires are only getting worse across the West. It's a foreboding trend: 2015 and 2012 were the only seasons with more acreage burned. Since the 1970’s, the number of large fires greater than 10,000 acres in size has increased seven-fold, and the official fire season has jumped from four to seven months long. In the Pacific Northwest alone, the area burned by uncontrolled wildfires each summer has grown by 5,000 percent over the last 40 years.

The situation becomes even more untenable when the looming threat of climate change is taken into account. As the West has warmed, the transition from spring snow to summer melt has come on earlier each year, summers are hotter than they once were, and droughts are more frequent. These climatological shifts combined to turn forests into tinderboxes this summer, as a series of heatwaves and droughts in early summer dried out trees just months after one of the wettest winters on record. In fact, one research group estimates that half of the forest area burned in the past 30 years can be attributed to climate change.

But a spark by itself is not enough to burn millions of acres – a wildfire needs fuel. And that is precisely what the US’s ineffective approach to forest management has provided.

Preparing to fail

The US Forest Service approaches fire prevention with a tactic known as “fuels reduction” – essentially, thinning out forests so that any wildfires that do start are not able to spread or intensify beyond firefighters' ability to control it. This involves clearing dry brush that allow sparks to jump, cutting small trees that burn readily, and pruning low-hanging branches that enable fire to expand upwards into forest canopies.

But while fuels reduction works in theory, its effectiveness is negated in practice by the sheer size of the West. The US Forest Service is responsible for more than 190 million acres of land, and fuels reduction efforts are targeted, tree-specific, and almost entirely manual. They are performed on an acre-by-acre basis, and they must be repeated every 10 years to deal with new forest growth. The result is that only a tiny fraction of forests categorized as "high-risk" - with little documentation of the logic behind that designation - sees fuels reduction. Additionally, it is impossible to predict whether these patches will coincide with the location of next summer’s heat waves, the primary driver of annual wildfire geography.

It turns out that only 1 percent of wildfires each year actually burn forest lands directly adjacent to areas where fuels reduction was carried out. That means that the more than $350 million spent annually on fuels reduction results in virtually no difference in the destructive capacity of wildfires.

At the same time, the outlook for the efficacy of fuels reduction is worsening thanks to the paradoxical way that the US government funds fire prevention. In contrast to other federal agencies like FEMA, which has money set aside for disasters like hurricanes, the Forest Service does not have a dedicated wildfire response budget. As wildfires have grown and become more expensive to fight over the last several decades, the agency has resorted to a practice known as “fire borrowing”: spending money originally earmarked for fire prevention to corral large fires and protect communities. The result is a vicious cycle wherein a particularly bad fire season in one region impacts the ability of the Forest Service to practice fuels reduction in another region – leaving that area more likely to burn out of control the following season. And as climate change increases the likelihood of large fires each summer, the cycle of bankrupting fire prevention is only going get worse.

Fighting fire with fire

What if, instead of throwing enormous resources at preventing and – when that inevitably fails – fighting fires, we simply embraced wildfires? Wildfires are a natural part of the lifecycle of arid forests: while today’s fires may be larger and more intense than in the past, the total area burning each year is still less than that burned naturally and by Native Americans prior to European settlement across North America.

Given the expansion of communities, recreation, and forestry in wildfire-prone regions, returning to historical levels of burning is not a feasible solution. But adding more fire may be exactly what we need to create less destructive burns.

Prescribed burning, in which wildfires are deliberately set to targeted areas, has proven an effective and safe technique for reducing the intensity and spread of natural wildfires since the Forest Service began the practice in 1995. Yet it makes up less than 10 percent of the acreage that sees fuels reduction efforts annually.

These intentional fires are set during the wettest part of the year, when only the wood that is most liable to burn – the same wood that would enable a natural wildfire to intensify out of control during the summer – will ignite. In this way, prescribed burns achieve the same end goal as fuels reduction, but without the manual effort of combing through the entire West. And in contrast to natural summer wildfires, prescribed burns are highly controlled with firefighters on standby to ensure that the flames stay within a predesignated perimeter.

Part of the reason this hasn't caught on is the combination of the human tendency to focus on short-term planning with the entrenched attitude within the US that all wildfires are bad. The risk of prescribed burns, a certain fire, is perceived to be much higher than a that of an uncertain natural wildfire - even though 99 percent of all prescribed burns remain within their predefined bounds while natural wildfires frequently consume entire communities. The immediate negative effects of smoke-filled air, charred forest, and short-term ecosystem damage are also prioritized over the potentially far worse effects of inaction. In addition, the Forest Service has faced an uphill battle communicating the benefits of prescribed burns thanks to the fact that Americans have been taught from an early age that wildfires are bad for communities and the environment - it's become known as the "Smokey Bear effect."

The same short-term focus, encoded in federal law, has also made conducting prescribed burns in certain high-risk regions legally challenging. For example, the Clean Air Act can in some cases prohibit prescribed burns due to the smoke they release, despite the likelihood that an uncontrolled natural wildfire will release far more smoke later in the summer. The Endangered Species Act can similarly impede burning: immediate, relatively mild damage by prescribed burns to forest ecosystems occupied by endangered species is barred, even if an intense natural wildfire may cause irreversible damage to the same ecosystem and its endangered species in the near future.

With climate change certain to make the annual wildfire season even more dire, the current situation is untenable. Where manual fuels reduction has failed, further crippled by fire borrowing with each new wave of devastating wildfires, prescribed burning offers a solution to the ever-growing stock of ready fuel distributed throughout our forests. Limiting the scale, rather than the number, of wildfires must be the new benchmark, and public opinion and environmental law must adapt to prioritize long-term ecosystem health over short-term discomfort. After all, with the West growing drier every year, the time has come to embrace wildfire – or else the fires may embrace us.

Michael Graw studies



Oregon State University


]]> Wed, 04 Oct 2017 10:00:19 EST We know terrifyingly little about how our bodies respond to pollutants, but that's changing Fish DNA can change in response to pollution. What about the rest of us? Anna Robuck Bad news: unless you live in a bubble, you are full of contaminants. Somewhat more reassuring news: every other living creature on Earth seems to share this condition with you.

Both terrifying and unifying, widespread contamination in humans and wildlife arises due to the slow and constant accumulation of chemicals in living creatures from their surrounding environment and diet, in a pathway known as bioaccumulation. Virtually everything you or any other living creature do contributes to this buildup: consumer products, food, textiles, building materials, household dust, drinking water, surface water, deep water, soil, and even air have all been found to contain multitudes of human-created chemicals. A recent study has even found microplastic fibers in municipal drinking water supplies across the country and globe.

Despite our chemical-laden lifestyles, we have almost no comprehensive idea how the accumulation of these compounds impacts living creatures, particularly wildlife, beyond acute effects. Yes, some chemicals have been shown to cause cancer or seriously mess up hormone production in humans or wildlife. But most chemicals in the environment primarily act by changing or weakening organisms' overall health in ways that don’t outright kill them.

This poor understanding stems from the fact that it is difficult to pin down definitive or causal relationships between pollution and its consequences when so many other factors could be at play in complex living systems. When a human gets cancer or a bird is having trouble laying eggs, it is nearly impossible to parse out how contaminants contributed in conjunction with variables like age, genetic inclination, nutritional state, and other environmental stressors.

Yet the challenging nature of the problem hasn’t dissuaded researchers from broaching it, and we are slowly starting to better understand how contaminants impact living beings. One recent study in particular helps highlight just how far we’ve come in understanding the sub-lethal metabolic effects contaminants have on wildlife.

Adapting to pollution, but at what cost?

The international team, led by Nishad Jayasundara of the University of Maine at Orono, focused on the mummichog, a common and well-studied fish that primarily lives in estuaries, marshes, and coastal environments. Mummichogs have long demonstrated a unique ability to adapt to polluted environments, with various lab and field research documenting genetic and physical adaptions to a variety of contaminants like heavy metals, pesticides, and other organic chemicals.

Apparently, this is a mummichog.

Brain Graitwicke

The team built upon this prior research by taking advantage of a natural experiment ongoing in the Elizabeth River along the coast of Virginia. Mummichog populations in the Elizabeth inhabit differently contaminated sub-environments within the larger river system. The team collected live fish from sites known to contain high, medium, and low levels of polyaromatic hydrocarbons (PAHs), a toxic and carcinogenic pollutant. The fish were then allowed to acclimate to environmental conditions in captivity before undergoing comprehensive evaluation.

After the acclimation period, the researchers first focused on genetics, and used previously existing work to identify genes that are different in contaminated and uncontaminated fish. They specifically looked at genes related to metabolism. From there, it was time for fish “Olympics.” The researchers made the fish swim until tired while measuring their oxygen consumption, metabolic rate, swimming ability, and tolerance to increased temperatures. The results of these measurements were fed into a statistical model to extrapolate how differential fish physical fitness impacts how the fish moves and responds within its environment.

So, this is a fish treadmill.

Using this multi-tiered strategy, the researchers described how pollution had cumulative effects at the levels of DNA, animal, and ecosystem. They found something surprising. Mummichogs deal with PAH exposure by changing their gene makeup.

Let that sink in a minute: fish DNA actually changes to cope with polluted environments. This alters metabolism and energy allocation, thereby compromising the fish’s ability to deal with other stressors in their environment. In this study, fish from polluted environments were less able to cope with increased temperatures; this has huge implications in a warming world where climate change is at work to increase water temperatures around the globe.

This is also troubling because mummichogs are considered extremely habitat-flexible, dealing with wide ranges in temperature and salinity. If any creature should be able to cope with thermal stress, it's these guys. Additionally, the modeling work suggested the compounded effects of altered genes, metabolism, and coping ability translates to fish being less capable of finding and traveling to an optimum environment, meaning contaminant exposure has the potential to alter the very way fish interact with the surrounding environment.

How does pollution effect the rest of us?

But what about all the wildlife that’s bigger than the size of a finger? How do contaminants sublethally impact cats, pigs, sharks, weasels, deer, or seabirds? Unfortunately, when larger creatures are factored into the conversation, we are reminded that we understand close to zilch when it comes to sublethal impacts of contaminants in wildlife.

A recent study focusing on Arctic seabirds embodies such existing gaps and highlights how tough it is to figure out how contaminants are undermining wildlife processes and function. Few studies have tackled contaminant impacts on metabolism in birds, thanks to how hard it is to compare features of very different species, as well as the fact that studying live creatures in the wild is much harder than analyzing samples. Those that have forged ahead looking at bird hormone production and metabolism have seen conflicting results.

So there is scant consensus regarding how birds metabolically respond to contaminant burdens. An international team led by biologist Pierre Blévin, of the Centre d'Etudes Biologiques de Chizé in France, recognized this uncertainty and implemented a study in an effort to better understand how contaminants are related to energy use in live birds. The team captured black-legged kittiwakes, a type of Arctic seabird, during their chick rearing season on Svalbard in Norway and took blood samples from captured birds for contaminant and hormone analysis. The birds were then rushed back to the lab via boat to take respirometry measurements. Respirometry essentially measures carbon dioxide respiration and oxygen consumption over time, allowing calculation of metabolic rate.

Hey look, it's a black-legged kittiwacke


Unfortunately, no clear picture emerged. The researchers found that different groups of contaminants were associated with variable metabolic rate and hormone levels. Increased concentrations of banned chlorine-based compounds, like pesticides or PCBs, were associated with decreased metabolic rate and hormone levels, while currently used perfluorinated chemicals, used as water repellants, were associated with an increased metabolic rate only in females.

These inconsistent results provide more questions than answers in terms of parsing out the greater impact of contaminants on birds. If organochlorine and perfluorinated compounds have opposite effects on metabolism, does this mean they cancel each other out? What is the net effect on bird energy use and what does this mean for bird migration? These birds migrate thousands of miles; do contaminant metabolic artifacts impact these feats?

It's hard to say: wild animals that live longer lives come with a history full on unknown events that may easily confound snapshots of metabolic rate or contaminant signature obtained within a study. In terms of methodology, transporting large wild animals alive for metabolism measurements is extremely time-consuming, expensive, and location-dependent, not to mention a permitting nightmare depending on the study location. This contrasts starkly with research solely measuring contaminant body burdens, which just uses tissue from dead animals. This is exponentially more straightforward, and cheaper, hence the abundance of reports describing contaminant levels in animals with little indication of how found chemicals are impacting the animal or its day to day function.

Still, these sorts of studies should not be avoided, but rather viewed as a challenge. The need to comprehend contaminant impacts in humans and wildlife only continues to grow, as thousands of chemicals are introduced each year to replace banned compounds or for novel applications, adding to the inundating chemical soup surrounding us.

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Tue, 12 Sep 2017 08:38:00 EST What modern conservationists can learn from humanity's long history with rainforests There's a growing body of evidence that humans have been modifying tropical forests for over 40,000 years Cassie Freund Pristine. Virgin. Natural. These are a few of the words that conservationists and ecologists like to use to describe tropical forests, as they conjure images of remote jungles hidden away in exotic countries.


Tropical rainforest in Papua New Guinea





A significant shift occurred around 10,000 years ago, though: humans transformed from foragers to farmers, and agriculture was born. Again, the earliest evidence comes from New Guinea, where our ancestors domesticated the banana and other tropical plants over 8,000 years ago.

These crops were planted in the rainforest alongside wild species, a technique which we now call agroforestry. Elsewhere, domesticated plants and animals, such as avocados and cassava in the Caribbean and Polynesia, are believed to have contributed to the extinction of some tropical trees, which were outcompeted by the newly arrived domesticated species. And, nowhere is the legacy of early human farmers more visible today than in the Amazon, where the distributions of existing Brazil nut trees line up almost perfectly with maps of 3,000-year-old human settlements.

A wild banana tree

Shashidhara halady


Our understanding of these cities has been greatly expanded by recent advances in remote sensing technologies. For example, LiDAR (light detection and ranging), a mapping technique using lasers, has revealed the extensive hydrological infrastructure built around 800 - 1,200-year-old Cambodia cities that enabled this early city to function in this tropical environment. This is where archaeology has great potential to inform forest ecology and conservation: we still have much to learn about architectural and agricultural techniques that allow humans to live and even prosper in tropical landscapes without completely obliterating them.




How can we move forward, now that the myth of the pristine rainforest has been busted? Roberts and his colleagues have a few ideas:


A Korowai man from the Indonesian province Papua

Wikimedia Commons



Cassie Freund studies



Wake Forest University


]]> Wed, 30 Aug 2017 08:57:45 EST Feeding the world as the climate changes will depend on genetic engineering CRISPR and other tech could help us produce more food, but only if we drop the GMO stigma Jackie Grimm Even small changes in temperature can have massive impacts on crop productivity. In the United States, a single degree of warming is expected to decrease corn yield by 10 percent. Worldwide, one degree of warming is expected to decrease crop productivity by 3-7 percent. Making matters worse, at the same time as crop yields are expected to decrease, the global population will continue to rise. If we do nothing to slow the effects of climate change, we risk a global food shortage that will affect us all.

Deep cuts to greenhouse gas emissions could do a lot to stave off disaster. But many researchers predict that even if we stopped all emissions tomorrow, we'd still experience some degree of future warming due to past emissions. So, even if we prevent additional damage, we'll still have to adapt to the changes in climate that are already underway.

Harvesting corn in Iowa.

Bill Whittaker

If we want to feed our growing population, we’ll have to tackle the problem of adapting agriculture to climate change head-on. Right now, one of our best hopes for adapting to a warming climate is a controversial one: genetically engineering our crops to survive better in higher temperatures.

Genetic engineering, the process of directly modifying an organism's DNA, strikes many people as an arrogant, unsafe intrusion on the natural world. The debate over GMOs (genetically modified organisms) has raged for decades, with opponents arguing that our capacity to tinker with nature has outpaced our understanding of the risks.

Concerns about the safety and ethics of genetic engineering are absolutely valid, but we should also realize that, in some cases, our ethical intuition may lead us astray. If you have ever grown a tomato plant, and you live somewhere other than the Andean region of South America, you have selected a plant with mutations that allow it grow somewhere it wouldn’t naturally do so. When we domesticated the tomato plant, we picked out mutant plants that were able to thrive in different areas of the globe. The difference between that process and genetic engineering is that scientists don't have to search for a rare mutant; they can create it themselves.

Speedier adaptation

CRISPR/Cas9 genome editing tools have made modifying DNA much easier. Using CRISPR/Cas9, scientists can create a DNA break in a specific place in the genome. They provide a strand of DNA that has a new sequence and the cell copies from that strand when it repairs the break, creating a genetic change.

Crops made using this technique are not, strictly speaking, GMOs, because they contain no foreign DNA. A wild tomato plant that was modified using CRISPR/Cas9 to be able to grow further north would be indistinguishable from the mutant plants that arose naturally, right down to the molecular level. And yet if engineers use genome editing to make that same change, it strikes many people as dangerous, even though the plants are completely identical.

Our food sources have already benefited from past forays into genetic engineering. Researchers' past efforts were focused on creating crops that are resistant to pests and disease. This is an important part of feeding the world – we could feed 8.5 percent of all the people on Earth with the crops lost to fungal pathogens alone. Climate change is making this problem worse: as warmer temperatures have spread toward the poles, so has disease.

But disease isn’t the sole consequence of climate change: the overall yield of food will likely drop because the areas where crops grow will no longer have the right weather for them to thrive.

Expanding crop-growing regions

One solution to this problem is to move heat-sensitive crops closer to the poles. But it’s not that simple: the seasonal cue that tells many plants when to flower is day length, and day length depends on latitude. That means you can’t take a plant that requires short days, move it further north, and expect it to produce fruit, even if it’s at the right temperature.

We've already modified tomatoes to grow in different regions and even make them easier to harvest.

U.S. Food and Drug Administration

Recently, researchers discovered the gene that represses flowering in tomato plants in response to long days. It's thanks to the variation in this gene that we're able to grow tomatoes further from the equator. These researchers used CRISPR to show that disrupting this gene results in plants that flower rapidly, regardless of day length. That means that if we want crops to grow at different latitudes, we won't have to find a rare mutant. By zeroing in on the genes that control day-length-sensitive flowering, we can create those crops within months.

Increasing yields

And when it comes to boosting crop productivity, one option is to create plants that convert sunlight into food more efficiently. That’s the goal of the RIPE (Realizing Increased Photosynthetic Efficiency) project, an international group working to increase crop yield by improving photosynthesis through genetic engineering.

Surprisingly, photosynthesis isn’t as efficient as it could be. Plants don’t adapt as quickly as they could to transitions between sunlight and shade. When there’s too much sunlight, plants protect themselves by releasing excess light as heat. But if a cloud passes in front of the sun, the protective mechanism lingers, which means less photosynthesis and lower yield. By speeding up the process of adaptation, RIPE scientists have shown that they can increase crop yield by 15 percent.

Although producing enough food to feed the world is crucial, genetic engineering isn't a cure-all. As long as we fail to confront the problems of war and unequal distribution of wealth, people will starve no matter how much food we produce. But adapting agriculture to climate change is unquestionably part of the equation, and genetic modification allows us to produce those changes quickly, easily, and safely.

Critiques of genetic engineering often focus on the most ethically questionable and unsettling research, but many scientists are doing work that could save the lives of millions. Keeping a closed mind risks demonizing a technology that may help us to survive.

Jackie Grimm studies

Molecular Biology


Princeton University


]]> Thu, 24 Aug 2017 09:16:10 EST Some good news: peatlands might help store more carbon as temperatures rise Don't drain these swamps Becky Parker Wetlands are, quite literally, land that is wet. Be it a marsh, bog, or a swamp, a wetland is defined by the presence of a high-water table (at or above the ground surface) at either certain times of the year or full time. They're also widely considered to be some of the most valuable ecosystems on Earth for their unparalleled ability to clean water, stabilize shorelines, and provide food and habitat for a huge variety of wildlife species. And they store vast amounts of carbon, helping to control global climate.

A new study from Tobi Oke and Heather Hager at the University of Guelph suggests that some wetlands might expand under current climate projections, which would mean that on top of providing all those other environmental services, they could hold onto more carbon as global emissions rise. That is, if they have room to expand. Parts of North America have already lost up to 70 percent of the wetlands present before European settlement due to historical urbanization and the gradual conversion of wild spaces to farmland.

A mossy peatland in Allt Lagan a' Bhainne, Scotland.

Sarah McGuire

The best carbon sequestering wetlands out there are peatlands. These are the bogs, fens, and swamps of the northern latitudes. You might have heard about peat in history class – it's the stuff Scottish and Irish peoples used to use (and still do in some areas) to heat their homes with in the absence of wood. It's also used in the production of fine scotches. Peat (or sphagnum) is a fast-growing and little moss that blankets the floors of most northern freshwater wetlands. In peatlands, growth is high and decomposition is especially low, so carbon is trapped for especially long times. Globally, peatlands make up less than 5 percent of the planet's vegetative cover, but they are thought to store about a third of all soil carbon. These are the carbon sinks we need to save room for.

It's uncertain how wetlands, including peatlands, will respond to ongoing global warming. Plants take in carbon dioxide as part of their normal life cycle, converting it to food for themselves and the organisms that consume them. Eventually, once the plants have died and decomposed, they release the carbon back to the atmosphere. Wetlands contain plant species that tend to grow fast and decompose very slowly, which means that wetlands store more carbon than they release. Some scientists have suggested that increasing temperatures will make wetland plants decay faster, releasing carbon from years of stored plant material and contributing to further atmospheric warming. Others suggest that warming could enhance productivity, so that any increase in decomposition might be offset by an equal increase in plant growth (potentially good news for mitigating the effects of climate change). For peatlands, Oke and Hager suggest it might be the latter.

Peatland distribution predictions from the study.

Tobi A. Oke and Heather A. Hager

Previous studies on peatlands used mathematical models to predict distribution from estimates of future annual temperature and precipitation averages. Peatlands like it cool and wet, so this seems sensible. But it's difficult to draw meaningful conclusions from averages. What if the average annual temperature stays the same under climate change, but summer temperatures increase? What if average annual rainfall increases, but so does temperature? How will the peatlands be affected?

To address this, the researchers looked at the seasonal climate differences in peatland areas for research published in PloS ONE earlier this year. They used four different 2050 climate models, produced by the Hadley Centre, NASA Goddard Institute for Space Studies, and Beijing Climate Center, and one they developed themselves for seasonal changes. They then predicted what conditions peat will develop in and modeled future distributions accordingly.

As it turns out, peatlands seem to be limited more by soil moisture than by temperature. Soil moisture acts as a buffer against increasing temperatures, keeping the wetland cool and preventing it from drying out during the warm months. Generally, the hotter it is, the more water plants will lose. Peatlands seem likely to persist in warming areas where precipitation is also increasing, or where they have some protection from the increasing temperatures. In North America, where it's dry and peatlands are maintained only by consistently low temperatures, there may be declines into the future as dry season temperatures increase.

This is important, because previous research suggested that warming would move peatlands northward into new territory, but Oke and Hager’s results suggest these regions will be too dry. Instead, their study suggests that peatlands will expand in areas where they're already common: the coastal regions where people want to build summer homes.

In total, Oke and Hager estimate peatland increasing by 15-38 percent into 2050, most of this gain occurring along the coast. Coastal areas of Canada and the United States are increasingly developed, with wild spaces giving way to urban areas where they used to be converted to farmland. We must save these spaces for nature, and the services nature provides for us. We cannot drain these swamps.

Becky Parker studies

Environmental Science


Nova Scotia Nature Trust


]]> Tue, 08 Aug 2017 14:56:11 EST Want to know where hard-to-find squid live? Ask their predators Look, sometimes you need to "offload water" from a giant albatross...for science Rebecca Flynn Curiosity and the search for answers are what drive scientists, sometimes to extreme lengths. A great example of just how far scientists will go is the research team that went to the Antarctic and set out to find where squid live by attaching GPSs to the large seabirds that eat them.

There are about 300 different squid species in the world, but scientists have yet to determine where all of them can be found. This gap in knowledge is unfortunate, because that information would allow researchers to start discovering the role they play in various food chains as well as to follow environmental and marine shifts through movement of these cephalopod populations.

Squid in the Southern Ocean, which surrounds Antarctica, are especially elusive. They are fast swimmers, and they live in a vast and remote open ocean habitat, including at its depths (up to 7,236 meters, or 23,740 feet). These squid are rarely caught in scientific nets. But one group of animals is good at tracking them down: the ones who eat them. Jorge Pereira, Vitor Paiva, and Jose Xavier, all at Universidade de Coimbra in Portugal, used wandering albatrosses in their study "Using seabirds to map the distribution of elusive pelagic cephalopod species" published in March.

An enormous wandering albatross


Using predators to track prey isn't a novel idea, but it is a brilliant one. It has been used by scientists in the Southern Ocean since at least the early 1990s. Many predators are, by nature, trackers. What better way for scientists to find prey species of interest than to let a predator lead the way to them?

There are some unique biases to consider when using a method like this. For example, the predator may prefer a specific size of prey and therefore only lead you to juveniles or adults. In addition, predators may only forage in certain areas that overlap with the prey species range, thereby revealing only part of the area they live in. However, it's a reliable method, and as one of the best options for these situations, scientists adopt a "beggars can't be choosers" mentality.

A team of scientists took advantage of the wandering albatrosses who rear their chicks on Bird Island, in southern Georgia. Wandering albatrosses are incredibly charismatic birds. They are some of the largest birds in the world and hold the record for largest wingspan (up to 11.5 feet). These albatrosses forage over great areas, including the cold waters of the Antarctic, but also the sub-Antarctic and subtropical regions. They can soar for several hours without flapping their wings and they spend most of their life in the air, only landing to breed and eat. They mostly feed on fish and cephalopods, but also on crustaceans, and catch their food during dives or when their prey is near the surface. They are listed as vulnerable by the International Union for Conservation of Nature (IUCN), so if climate change affected their food sources, the entire species could be endangered.

The scientists outfitted 17 of them with a GPS logger, activity recorder, and stomach temperature probe for a single foraging journey. The combination of information they gleaned allowed them to piece together a story of the journey.

As the albatrosses journeyed, searching for food to bring back to their chicks, the GPS tracked their locations. When a bird would dive into the water to capture prey, the activity logger would record it. When an albatross ingested prey, that prey item was colder than the normal body temperature of the bird, causing the temperature logged by the stomach temperature probe to drop.

When the bird returned, the researchers used a method called water off-loading to collect the contents of their stomachs. They inserted a tube through the bird's bill until it reaches the stomach, pour warm water in until the stomach is full, then remove the tube and massage the bird's stomach until it vomits into a bucket (this process is repeated twice to ensure all contents were flushed from the stomach). The scientists then went through that vomit to identify what the albatross had eaten. Sometimes science isn't pretty, and it often smells bad.

The researchers found 22 squid specimens representing 11 species. Then, working backwards from the sizes and masses of the squid bits, researchers mapped the distribution of various species in the Southern Ocean.

The surprising Galitheuthis glacialis

Carl Chun

Some of their findings surprised them. One species, Galiteuthis glacialis, was found across an oceanic front, the boundary between distinct water masses that move in different directions and often have different temperatures, salinities, and densities. Scientists previously thought that cephalopods did not cross oceanic fronts. If a species can cross them, it means they can survive in more diverse areas than previously thought and that these squid are not held back by these physical barriers.

In the future, the authors wrote that they would like to take the study even further, adding another item to the technological outfit of the albatrosses: small cameras. Of course, that means that, in addition to wading through vomit, they'll be able to watch the albatrosses catch prey. It will make identifying what they ate much easier and address some questions that they can't with the current system. For example, some fishermen in this area use one species of squid as bait, so it's possible the albatross pick them up from behind fishing boats and the squid don't actually live in that area.

Conducting scientific research can be dirty, smelly, and uncomfortable at times, but making new discoveries about how the world works makes these extreme measures well worth it.

Rebecca Flynn studies

Environmental Science


University of Rhode Island


]]> Thu, 01 Jun 2017 11:11:38 EST We've poured thousands of manmade chemicals into the ocean. Now they're mixing in unpredictable ways. We're just starting to learn about the effects of POP soup and what we can do about it. Anna Robuck In many ways, the story of modern human history is the story of chemicals. Humans have created over 86,000 compounds, and today’s consumer, medical and industrial products use over 30,000 of them. As much as our prodigious production has made our lives easier, there’s a significant dark side to our chemical habit. A subset of these compounds have negative impacts on humans and wildlife due to their persistence and tendency to accumulate over time in organisms and sediment. Scientists call these compounds persistent organic pollutants, or POPs.

A model of a DDT molecule


Concern about the effects of POPs began following the publication of Rachel Carson’s 1967 book Silent Spring. Carson noticed that DDT and other pesticides were wreaking havoc on bird reproduction, and argued that we start regulating chemicals to manage their effects on wildlife. Since Carson’s call to arms, POPs have received plentiful research attention and subsequent regulation managing their use. Yet biological risk from POPs is far from resolved.

Killer combos

Thousands of new chemicals are introduced every year to replace banned compounds or use in new applications. The ongoing introduction of POPs into the environment has created a unique phenomenon called mixture toxicity. The idea is that once compounds end up in the environment, they freely mix together in air or water and form complex amalgamations that impact surrounding plant and wildlife in unpredictable ways. In some cases, the combination of multiple compounds is more potent than the sum of the individual parts, meaning a POP mixture may impact organisms in ways that are hard to measure. 

Most traditional POP research doesn’t look at mixture toxicity. Instead, it generally focuses on identifying one or two types of POPs in a given environment or assessing a creature’s response to one type of chemical. That made a recent study of phytoplankton – the tiny ocean plants that provide food for many different ocean ecosystems – by Pedro Echeveste and a team of international researchers unique. For the first time, they looked at how ambient POP mixtures impact phytoplankton in the real world.

Shipboard science

Echeveste and his research team believed that phytoplankton aren’t just subject to one or two types of POPs in natural settings. Instead, they swim in a veritable POP soup consisting of hundreds of thousands of different contaminants. Earlier unrelated work from the South Atlantic Ocean suggests that 90% of the contaminants prone to build up in living tissue within this POP soup are not monitored or are unknowns, meaning marine creatures are constantly swimming in POP mixtures we know essentially nothing about. 

To learn more about the POP soup, Echeveste and his colleagues employed a multi-year, global strategy to address their research question. They collected water from the Northeast Atlantic, the coastal Mediterranean Sea, and two locations in the Southern Ocean. They then extracted POPs from collected water using a special type of absorbent called XAD-2, a powdery substance that essentially “grabs” POP molecules out of water. 

Unsurprisingly, they found that water from the Atlantic and Mediterranean locations – closest to large population centers – contained higher measured POP concentrations. They then took phytoplankton samples from the same locations, placed them in sample bottles, and added variable amounts of POP mixtures isolated from each respective region.

These experiments took place aboard a ship located within each respective water/phytoplankton collection region. Although conducting research on boats is more expensive than lab settings, the researchers wanted to ensure that treatment bottles were kept at native light levels and water temperatures. They accomplished this by placing sealed sample bottles into a large tank on the deck of the boats and pumping ambient seawater into the tank to keep the phytoplankton surrounded by the right water temperature. The tanks were also covered with netting to simulate light conditions at a depth of 5 meters. 

Researchers set up tanks similar to the pictured setup to carry out the incubation experiments aboard a research vessel in each region where phytoplankton and water were originally collected.

Anna R. Robuck

Small creatures take the biggest hit

With these experiments, Echeveste and his group found that most of the phytoplankton from all four locations experienced either a population decline or decreased growth rates when subjected to contaminant mixtures five to ten times natural concentrations. They also noticed that smaller phytoplankton, or, picophytoplankton, were particularly sensitive to the pollutant mixtures. The disproportionate effects of POPs on the tiniest phytoplankton doesn’t bode well for marine ecosystem health. Smaller sized phytoplankton groups are generally better at handling nutrient-poor or stressful conditions than their larger counterparts. Scientists expect that marine food webs will become increasingly depending on these smaller plankton, which should become more dominant as climate change makes it harder for larger plankton to thrive. This means that the ocean is becoming increasingly reliant on organisms that are more likely to be impacted by complex POP mixtures.

Picophytoplankton are very tiny members of the phytoplankton community, ranging from 0.2 to 2 µm in size.

Daniel Voulet, CNRS

Contaminants and climate change: a one-two punch?

The authors of the study pointed out that POP mixtures aren’t the only stressor impacting phytoplankton communities. UV radiation and temperature can both exacerbate the effects of POPs on phytoplankton communities, and these stressors are likely intensifying in some regions as climate change manifests itself dynamically across the globe. The experiments in this study didn’t take into account these other factors. Acting in concert, stressors such as light, temperature, and exposure to complex POP mixtures are likely to further degrade global phytoplankton communities.

Phytoplankton form the basis of marine food webs and actively participate in the carbon cycles that impact our climate. This study provides evidence that POP exposure, even at low concentrations, influences all of those important processes across the vast expanses of the global ocean. Given that over half of the global human population lives near coastal areas or relies on the ocean for food or a livelihood, the fact that POP mixtures are impacting the base of this important food web across the globe should be cause for alarm.

We need more research to better understand phytoplankton responses to realistic, complex POP mixtures in combination with other natural stressors, as well as to figure out how POP impacts trickle up into the rest of marine food web. But the potential consequences are already severe enough to merit increased public awareness about the use and fate of POPs. We should be taking steps to prevent introducing POPs into marine ecosystems through education, civic involvement, making legislative demands, and making smart consumer choices. 

Anna Robuck studies

Marine Science


University of Rhode Island


]]> Mon, 22 May 2017 09:23:21 EST Seagrass meadows protect fish, coral and humans from disease – and we’re losing them This seemingly mundane plant might be more important than we realize. Megan Chen If you’ve seen seagrass meadows on the ocean floor while snorkeling and not given them a second thought, you’re not alone. Seagrass may seem mundane, but the plants have a huge impact on the livelihood and well being millions of people around the world. 

Lush underwater seagrass meadows help protect ecosystems we rely on for food, against erosion and extreme weather – reason enough to be alarmed that we are losing them at relatively high rates. We’re now learning that they’re important for another reason too: like their land-based counterparts, seagrass may help reduce the risk of disease outbreaks in fish, invertebrates, coral reefs and even humans.

We’ve long known that terrestrial plants combat bacteria and other pathogens by producing natural pesticides, competing for nutrients, and altering the chemistry of the soil and water. The marine plants that make up the most common coastal ecosystem on earth appear to have similar capabilities.  Previous lab studies have even shown that extracted chemicals from seagrasses kill pathogens. Now, for the first time, scientists have found evidence that seagrasses do this in the wild as well.  

Birds-eye-view of site locations in Sulawesi, Indonesia

To study the pathogen-killing ability of seagrasses, an international team of scientists lead by Joleah Lamb of Cornell University collected water samples from multiple sites at different depths from four islands along the western coast of Sulawesi, Indonesia. They chose these locations because the islands shared important characteristics: sediment type, human population density, the absence of basic sewage treatment, and thin soils that do not hold wastewater and are susceptible to pollution.  While sampling sites in different locations can never be identical to each other, choosing sites with similar characteristics controls as many variables as possible and allows analysis to focus on the relationship between the presence of seagrasses and pathogen levels in the water.  

Benchmark Bacteria

In order to assess how seagrasses might affect human health, the researchers tested 400 water samples for Enterococcus, a lactic acid bacteria that can cause urinary tract infections, meningitis, and other health problems. The U.S. Environmental Protection Agency uses the bacteria as an indicator of human health because it’s often found alongside other disease-causing pathogens in wastewater pollution.

The team analyzed water samples for Enterococcus levels, and found that samples from locations closest to the shore contained 10 times the EPA’s recommended levels for recreational water. In other words, you wouldn’t want to swim there. However, samples taken from sites with seagrasses nearby had 3 times lower pathogen levels compared to sites without seagrasses nearby. Their findings weren’t limited to Enterococcus. The team also found lower levels of pathogens that cause everything from disease in fish to food poisoning in humans in locations with seagrass nearby. 

Coral Care

The researchers also visually examined more than 8,000 corals for signs of damage associated with coral bleaching, coral disease, and physical damage from moving debris. Unsurprisingly, they found that corals at sites with seagrasses nearby had half the amount of diseases than corals without seagrasses nearby.

Ria Tan via flickr, CC-BY-NC-ND. Coral reef photo credit – Tony Hudson via Wikipedia Commons CC BY-SA. High five – Larske via Wikipedia Commons CC BY-SA

Coral reefs, one of the most important ocean ecosystems on earth, face increasing threats from climate change, ocean acidification, and development. That makes understanding seagrass, which contribute to their health, even more important. Unfortunately, seagrasses are facing their own set of threats. Even though they’re a fairly common ocean ecosystem, nearly 20% of seagrass species we’ve studied are endangered, mostly due to the compounding effects of destructive human activity like dredging, agricultural and construction runoff and even boat anchors and propellers.

The good news is that there are ways to prevent seagrass decline. Creating international legislation to protect seagrass meadows would be a strong start. These agreements should call for people working near seagrass meadows to create strong management plants that prevent or minimize excess fertilizer runoff and construction dumping, prohibit boat anchoring and dredging, and manage fisheries so top predators aren’t eliminated from ecosystems. We can also restore seagrass by planting or seeding, which is how communities in Florida and the Chesapeake Bay were able to successfully restore seagrass.

We all stand to lose from seagrass depletion. 275 million people live in coastal communities that depend on coral reefs for their lives and livelihoods. Even if you don’t live near the ocean, you probably interact with it. Not getting a disease or infection when you eat seafood or go swimming at the beach? That’s worth paying attention to seagrass, even if it’s unremarkable at first glance.

Featured Article

  • Lamb, JB, van de Water, JAJM, Bourne, DG, Altier, C, Hein, MY, Fiorenza, EA, Abu, N, Jompa, J, Harvell, CD (2017).  Seagrass ecosystems reduce exposure to bacterial pathogens of humans, fishes and invertebrates.  Science 355(6326): 731-733. doi: 10.1126/science.aal1956

Megan Chen studies

Marine Biology


Smithsonian National Museum of Natural History


]]> Mon, 03 Apr 2017 13:25:46 EST Conservationists can't tackle all of the ocean's problems at once, so scientists are helping them triage The ocean contains many vulnerable ecosystems that need protecting. So where should we start? Abrahim El Gamal The word triage, derived from the French trier, "to separate out," entered the English lexicon during World War I, when the Brittish found themselves fighting alongside the French. The four-year struggle ravaged Europe, leaving over 20 million soldiers injured and at least 8 million dead. Ironically, the French may have first used the term in the 1800s during the Napoleonic Wars, when they fought against the United Kingdom. In everyday civilian life, medical triage is still used in hospital emergency rooms and acute emergencies where medical professionals with limited resources need to rapidly assess the needs of many patients. Despite its flaws, the triage system strives for the best overall healthcare outcome by prioritizing treatment of the most vulnerable.

Ecosystems as Casualties

In a sense, human-driven global warming has declared war on the world’s ecosystems, and the casualty of this war is biological diversity. On land, the increasing occurrence of wildfires is interrupting natural cycles of habitat recovery, making forests and grasslands less hospitable to life. At the poles, ice melt is driving animals that live on ice shelves to extinction, while the accompanying sea level rise is reshaping the world’s coastlines. In the ocean, increasing seawater temperatures are killing off coral reefs that support the most species-rich ecosystems on the planet.

Bleached coral on the Great Barrier Reef in Australia.

"Bleached coral (24577819729)" by Oregon State University

At the same time, humans are fishing, hunting, mining, drilling, and otherwise exploiting these very same ecosystems. Like the doctor on the battlefield or the nurse in the emergency room, conservationists face the dilemma of triaging efforts to ameliorate the environmental one-two punch posed to ecosystems by climate change and direct human exploitation.

In one of the first studies of its kind, a multinational team of scientists hailing from institutions in Spain, New Zealand, and Australia looked at the dual impacts of climate change and overfishing. Their findings provide a framework for prioritizing marine conservation efforts. 

Mapping Diversity and Impact

Coral reefs, which cover less than one-tenth of the ocean floor, but are estimated to harbor upwards of a quarter of marine species, are among the most biologically diverse habitats on earth. They are rivaled only by terrestrial rainforests. Reefs support ‘ecosystem services,’ a term used to describe the resources they provide to humans. Some ecosystem services provided by coral reefs include fish populations, erosion control, and disinfection. Fish are part of a larger picture of biological diversity, but as predators their abundance can be used as a proxy for diversity in reefs. As a result, scientists can use fish populations to understand the health of complex coral reef ecosystems found in the tropics.  

But global fish populations don't just fluctuate based on reef health. They're also facing unprecedented pressures from hyper-efficient modern commercial fishing operations. It's impossible to stall the the multi-billion dollar commercial fishing industry, so lead scientist Francisco Ramírez and his colleagues focused their efforts on hotspots of biological diversity particularly susceptible to commercial fishing. They hoped to identify the marine habitats most affected by both global warming and commercial fisheries, helping conservationists prioritize interventions in these most vulnerable locations.  

To find these locations, Ramirez an his team had to collect and combine multiple types of data: the biodiversity of ocean habitats, historical ocean warming records, and historical fishing records.

To determine the areas with the highest occurrence of the largest number of species—the greatest biodiversity—Ramírez and co-workers mapped the global distributions of over two-thousand marine species, including mammals, birds, and fish. They then used this data to create a convenient index that could be used to compare the biodiversity of the world’s oceans.

The team next sought to assess how particular ecosystems might have been affected by the dual impacts of climate change and commercial fishing. To look at climate change, Ramirez and his colleagues curated three decades of satellite images, constructing a kind of stop motion animation documenting changes in ocean currents, sea water temperatures, and levels of photosynthesis by tiny plankton that form the foundation of the marine food chain.

NASA Earth Observing System Data and Information System (EOSDIS) data on NASA Worldview provides the capability to interactively browse and layer satellite imagery and data. You can observe the entire Earth as it looks during specific times and dates. Similar data was used to create animated timelines of ocean currents in this research.  

Static image from interactive NASA Worldview

Then, the team focused on fishing, overlaying satellite observations with fishing records collected since by commercial fishermen, which provide a rough picture of changes in ecosystem composition over time.

As with biodiversity, the researchers combined all of this data into a convenient index that combined seawater temperature, plankton photosynthesis, and changes in ocean circulation to compare the cumulative environmental impacts in specific locations.

Hotspots of Climate Change Impact

Ramírez and colleagues noticed a few interesting things. They saw a general warming trend in the world's oceans and a corresponding deceleration of the huge current (a.k.a. the “thermohaline current”) that connects the world’s oceans, resulting in changes in transport of cooler waters and nutrients around the world’s oceans. 

But they found that the effects of these wider trends weren't evenly distributed. Some ecosystems were deeply impacted, while others seemed to be going about their business as usual. Unfortunately,  many of the areas most affected by warming coincided with hotspots of marine biodiversity. Worse still, by examining over half a century of fisheries data, the team found that the areas most vulnerable to climate change were also some of the most overfished waters.

These findings lead Ramírez and his team to identify what they believe to be the six most vulnerable marine ecosystems – the places where the highest biodiversity coincides with largest environmental and fishing impacts. These hot spots include some of the most productive waters on Earth, falling mostly in the warmer waters of the southern hemisphere and including areas in the Atlantic, Pacific, and Indian Oceans. 

1. The westernmost vulnerable area includes the central-western Pacific waters of Peru and the Galápagos Archipelago.

“Galapagos sea lion, underwater, up close”

Photo by Derek Keats via Flickr


"Sea lions on the rocks at Cabo Polonio, Uruguay, 2005"

Photo by Kenspuss via Wikimedia Commons


This is the shell of the sea snail 'Turbo imperialis' collected near Toliara (Tulear), Madagascar.

Photo by JialiangGao via Wikimedia Commons


"School of Pterocaesio chrysozona in Papua New Guinea"

Photo by Brocken Inaglory via Wikimedia Commons

5. Waters surrounding New Zealand and Eastern and Southern Australia were considered the fifth hot spot at the southwestern Pacific.

"Sea at West Coast, New Zealand"

Photo by Ulrich Lange via Wikimedia Commons

6. The sixth hot spot included marine areas in Oceania and the central Pacific Ocean. 

Thousands of species of jellyfish like this species of box jelly can be found amongst the diversity of flora and fauna in this hotspot. 

Photo by Jan Bielecki et. al via Wikimedia Commons

While the researchers were able to identify the areas conservationists should focus on first, it won't be easy. Many of the most vulnerable ecosystems exist in sovereign waters governed by a particular country. Multi-national conservation efforts will be necessary to reverse the trend of ecosystem destruction due exploitation of habitats already impacted by climate change. Saving these particularly delicate regions will require collaborative, sustained efforts. Studies like this one that help conservationists triage and focus their efforts are a good place to begin.

Featured Paper

  • Ramírez, F., Afán, I., Davis, L. S., & Chiaradia, A. (2017). Climate impacts on global hot spots of marine biodiversity. Science Advances, 3(2), e1601198.

Abrahim El Gamal studies

Marine Chemical Biology


Scripps Institution of Oceanography