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Climate Change Series: Where Science And Ethics Meet

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What do we mean when we talk about the imminent threat of rapid and irreversible climate change?

And what ethical responsibilities do we — especially those of us in the societies most responsible for the emission of destabilizing greenhouse gases — have in the face of that threat?

Harvard chemist James Anderson and Northeastern philosopher Ronald Sandler examine the interplay of science and ethics as Cognoscenti and the Open Classroom kick off our series Climate Change. Challenges. Solutions.

James Anderson

James Anderson is the Philip S. Weld professor of atmospheric chemistry at Harvard University, where he directs the Anderson Research Group on the chemistry and physics of climate and earth system change.

"Global warming," which sounds gradual and reversible, does not begin to describe the challenge we face today. The obstacle ahead is unstable and irreversible – it is climate change.

"Unstable" because the warming of the earth's atmosphere can set up feedback loops that dramatically change the earth's fundamental climate patterns. "Irreversible" because once these changes take place, we know of no way to undo them and return to the climate patterns that have existed throughout human civilization.

'Global warming,' which sounds gradual and reversible, does not begin to describe the challenge we face today.

Take the Arctic ice cap for example. For over 100,000 years, the interplay of polar ice caps with tropical heat has dominated, and largely determined, the earth's climate patterns. This permanent floating ice on the Arctic Ocean has remained intact for at least the last 130,000 years — perhaps much longer. In the face of rapidly increasing CO2 concentrations for fossil fuel combustion, five years ago climate scientists believed the Arctic ice cap would survive until the end of the century. Three years ago, they believed it would survive until the middle of the century: 2050. Today, based on direct observations, they believe that the permanent ice of the Arctic Ocean will be gone by 2025, if not sooner.

The removal of that ice has a huge effect. Greenland — which has 7 meters (23-feet) of sea level rise contained in its glacial structure — was effectively sealed off for the last 2.5 million years by the Arctic ice cap. Now, with the warming of water and air in the Arctic, Greenland’s glaciers are rapidly becoming unstable. This instability, and the feedbacks associated therewith, both speed the rise in sea level and render the situation irreversible. To give just one example of what rising sea levels mean, a 3 meter rise in the North Atlantic would put the entire southern quarter of Florida (including all of the Miami metropolitan area, currently home to nearly six million people) underwater.

Now add in the projection that global power demand (which is basically determined by population consumption levels per capita) is expected to rise from the current 15 terawatts to 40 terawatts annually by 2050. These 25 terawatts of increased energy demand is equivalent to the construction of 750 large fossil fuel burning power plants per year for the next 40 years. This comes at a time when we need to drastically reduce greenhouse gas emissions.

Despite the enormous — even catastrophic — challenges we face, I'm not terribly pessimistic. We're simply going to have to start extracting carbon from the atmosphere. The current price on that is in the range of $200 per ton of carbon. It is scientifically and technologically possible; we just need to make the investment, and we need to rapidly reduce emission of CO2 from fossil fuel combustion.

The U.S. is endowed with renewable energy to a profoundly important degree (as is China, the other leading source of greenhouse gas emissions). Fifteen percent of the area of the Middle West could generate one-third of our primary energy from wind power. Approximately 10 percent of the area of Arizona would give us another one-third from solar thermal. Energy storage and energy intermittency are not the serious drawbacks they were once believed to be.

Five years of a reasonable reapportionment of how we invest our resources — an investment into building a new, renewable energy infrastructure — gets us onto an entirely new track, one in which our standard of living will be improved, while we initiate a new path for which our and our children’s future is both respected and protected.

Ronald Sandler

Ronald Sandler is associate professor of philosophy at Northeastern University and director of the university's Ethics Institute.

Fundamentally, global climate change is an ethical problem, a question of right and wrong. It's also a political, scientific, technological and economic problem. But recognizing climate change as primarily an ethical problem has implications for the urgency with which we address it and the resources we're willing to commit to dealing with it.

Human societies, as well as plant and animal species, have always had to adapt to ecological change. But as the rate of change accelerates with global climate change, adaptation becomes increasingly difficult.


According to a 2008 report by the International Union for Conservation of Nature and Natural Resources (IUCN), 35 percent of bird species, 52 percent of amphibian species and 71 percent of coral species have traits that put them at an increased  risk of extinction from global climate change. The Intergovernmental Panel on Climate Change (IPCC) concluded in 2007 that 20 to 30 percent of species are likely to be at increased risk of extinction on lower greenhouse gas emissions scenarios, with 40 to 70 percent extinctions predicted on upper-level emissions scenarios. To put that in context, the historical extinction rate is .0001 percent or, one species per million, per year.

Already it's estimated that climate change is implicated in 300,000 deaths per year due to its contribution to food insecurity and extreme weather events. Currently there are over 20 million environmental refugees — people who've had to move because the ecological conditions where they lived could no longer support them.

In thinking about the ethical implications of global climate change, we can start by recognizing the tremendous amount of human suffering associated with it — with most of that suffering borne by individuals and countries that are poor. In addition, the hardships from global climate change are largely caused by those of us in high-consumption, high-emission countries. Worse, from an ethical perspective, we now know we are causing these harms to others. So climate change is a human rights issue as well. Our actions are undermining other people’s abilities to meet the most basic security and survival needs.

There's a justice dimension too: Those most exposed to the hazards of global climate change have the least resources to adapt. But they're also the people least responsible for global climate change, because they consume less, use less energy and are responsible for low levels of greenhouse gas emissions. And, there's an inter-generational justice dimension. Current generations enjoy the benefits of a high-emission lifestyle, but the costs will be paid by future generations. There are lots of theories of justice, but here's a basic notion they all share: Those who get the benefits should shoulder the associated burdens.

It is ethically preferable to prevent human rights from being compromised and avoid unjust harms from occurring, than to make restitution after the fact. Moreover, there are at present no adequate adaptation options. We do not have institutions or strategies that can scale up to dealing effectively with, for example, hundreds of millions of climate refugees, or preventing the extinction of 10,000 species a year.

Furthermore, adaptation is typically local where mitigation has global impacts.  If New York spends huge amounts of money building seawalls to protect the city against rising sea levels, that does nothing to help Manila, or Capetown or Lima. But if we reduce emissions enough to minimize sea level rise, that benefits everyone, including the poor.

So, ethically speaking, our response to global climate change needs to involve aggressive, immediate mitigation.

Accomplishing a low-emissions trajectory undoubtedly requires enormous technological innovation and change — e.g. developing alternative energies and dramatically increasing energy efficiency. However, we'll have to make behavioral and cultural changes too — e.g., reducing fertility rates, eating less farmed meat (12 to 16 percent of greenhouse gas emissions come from animal agriculture), and reducing deforestation — in order to effectively alleviate some of the harms climate change has already begun to cause.


This program aired on January 16, 2013. The audio for this program is not available.

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