Week of 1.9.09
Transcript: Sea ChangeBRANCACCIO: You see President Bush is leaving us with a farewell gift to the environment... specifically the oceans. This week, he designated three spots in the Pacific as
Week of 1.9.09
Transcript: Sea ChangeBRANCACCIO: You see President Bush is leaving us with a farewell gift to the environment... specifically the oceans. This week, he designated three spots in the Pacific as national marine monuments...about 200-thousand square miles become sanctuaries. But that's a drop in the sea compared with the emerging new threat to all the world's oceans—global warming. Scientists are gathering data suggesting oceans are being set up for sudden change. And an abrupt shift to a system as vast as our oceans is a something that needs your attention. Steve McCarthy produced our report.
We landlubbers tend to think of the shoreline when a visit to the ocean is proposed. But scientists, including those at Woods Hole oceanographic institute in Massachusetts, have to go deeper and get beyond the surface of the problem.
CURRY: Well, the oceans cover 75 percent of the earth. They interact with the atmosphere and they basically set the stage for climate—and for weather. When you start to change something as big as the ocean in as big a way as we're doing it. Warming it up, acidifying it, melting all the ice, you're gonna change fundamentally how the climate system works. That is something we all should be really concerned about.
BRANCACCIO: Acidifying, warming, melting that's a lot but don't worry, ocean scientist Ruth Curry is about to teach us some fascinating lessons about how this works.
CURRY: What most people see about the ocean is what you could see from shore. Maybe what you could see from an airplane. Even what we can see from a satellite covers only the skin of the ocean.
We need to go out there and understand what the whole ocean system is doing. Both physically and chemically.
BRANCACCIO: Curry is a senior research specialist at Woods Hole, which let us aboard one of their scientific vessels—The Oceanus—as it set out for a voyage.
CURRY: In fact it's only been in the last decade or two that the idea of the deep ocean changing has even gained some—viability. In other words, people thought that the deep ocean was static for the longest time. Not that it didn't move. But, that it didn't change. And that is something that has definitely been shown to be wrong in our thinking.
BRANCACCIO: What worries scientists like Curry is the danger that global warming could set off unpredictable chain reactions in the seas....that human activity could alter entire ocean currents, alter the chemistry of the water, and wipe out a wide variety of marine life.
There's been a lot of questionable thinking, including the idea that the past is a guide to future performance. It doesn't work for investing and it's a bad way to predict the future of the earth. Take the fact that global temperatures have gone up just a degree centigrade over the last century. Some take solace in how that rise has been so gradual. But scientists say it's been gradual in large part because the oceans have been sucking up a lot of the extra heat. It's like the way a paper towel blots up water. And like a paper towel, eventually things get saturated and we could be approaching a time when the ocean hits its limit.
CURRY: We've been aware of global warming for several decades now. We haven't taken any substantive action. And we're now nearing what—many scientists would call tipping points. And the best example of that, I think, is the arctic sea ice.
BRANCACCIO: One of the reasons the ocean can store so much energy says Curry is because of the ice at both poles. And here's the thing: the presence of ice in the ocean allows the water to take up much more heat. Policymakers having trouble coming to grips with global warming, might want to try a simple experiment.
CURRY: Unlike most experiments that we film on TV, this is something you can do at home.
BRANCACCIO: Call it our little "ice bath experiment" and it will, says Curry, show how ice buffers our climate system...until it hits a tipping point.
CURRY: So I've just got a beaker here and put fresh water into it and ice cubes. And we've been taking it's temperature.
BRANCACCIO: And we're gonna pretend, in this model, the water's the ocean, the ice is ice in the ocean.
CURRY: The arctic sea ice.
BRANCACCIO: Arctic sea ice. And the heat that we're going to apply to this ice water-
CURRY: Is global warming.
BRANCACCIO: —is global warming.
CURRY: You're gonna read off temperatures every 30 seconds. I'll type the temperatures in and we'll make a plot of what goes—what happens. What you might want to do is maybe to help the stirring action.
BRANCACCIO: Stir the cocktail?
CURRY: That's right.
BRANCACCIO: Where's the vermouth?
CURRY: Okay. All right. Now, let's go ahead and turn on the heat.
BRANCACCIO: All right.
CURRY: