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: Go to high.
CURRY: High heat, yeah. Build up of greenhouse gases was very sudden. This hot plate is enough to make water boil.
BRANCACCIO: All right. Okay, all right, we're at one degree at two minutes.
CURRY: One degree. So it hasn't changed.
BRANCACCIO: No. This experiment takes a little time so we'll check back to it in a few. Meanwhile, back on the Oceanus....
There's a high-tech effort under way to gather data on what some ocean scientists believe could be the biggest shock to the oceans in 100 million years.
They're yanking on a Moored Profiler. It's a RIG created by the Woods Hole Institute to measure the ocean currents and temperature during the past year. It's moored to the bottom of the sea and slides up and down its tether to take measurements at different depths. Sensors on the profiler measure water temperature, saltiness, speed of the current and other properties. It's not surprising that clever engineers have now come up with ways to monitor the ocean in three dimensions. What's surprising is how long it's taken. A recurring theme when talk about global warming and oceans is how little we have measured so far and how much we still don't know.
The team pulls up these things up about once a year and collects data from a memory stick inside...then puts another profiler to work. They started deploying these in 2001 and there now six of them out into the Atlantic.
Another gizmo on the Oceanus is the "c-t-d" - measuring conductivity, temperature and depth. This is one scientists keep a hold of...after lowering it into the water and monitoring the results in real time.
Ruth Curry says they are collecting data to monitor how the ocean moves warm water from the tropics north to the arctic where it cools down. The cold water then sinks and travels south back to the equator.
CURRY: It has been characterized as a conveyor belt.
BRANCACCIO: It's called the Atlantic conveyor and it has a lot to do with the climate of North America and Europe. It's not to be confused with the Gulf Stream - which is on the surface and is driven by wind. The conveyor is three dimensional.
CURRY: The ocean conveyor, it acts a lot like the—baseboard heating system, or a radiator that heats our houses. You have warm waters that are circulating from the equator, up towards the arctic. And along the way, that ocean heat is warming the overlying atmosphere, okay. So, it's releasing its heat to the atmosphere. It's keeping the air warm. This has the effect of—of—mod—modulating or—or—making warmer the climate, especially, of Europe—and Asia because they are downstream, the winds that blow over the ocean.
BRANCACCIO: But there's mounting evidence global warming could alter this vast conveyor of ocean water.
In the science fiction movie "The Day After Tomorrow", the conveyor stops and Hollywood envisioned some kind of sudden ice age.
But scientists, on the other hand, are less worried about the conveyor grinding to a halt but they are watching to see if the thing slows a bit. It's becoming a planet-wide experiment with the results not yet known.
CURRY: A warmer ocean and a fresher ocean, which are both taking place because the oceans are warming up, and the ice is melting, and flowing into the ocean. Both of these—change, or have the potential to change that—circulation.
BRANCACCIO: For the conveyor to work, you need a lot of arctic ice to chill down the incoming surface water and send it on its way back south along the ocean bottom. But remember the ice is having a hard time, both in the Arctic and in the little beaker on the hot plate in our science project.
CURRY: The volume of ice has really—decreased now
BRANCACCIO: All right, two and a half degrees.
CURRY: Okay, 2.5. All right, we're getting into—nearly ice free arctic here.
BRANCACCIO: We've been heating the ice water—simulating global warming in the arctic—for seven and a half minutes now and the water temperature has only gone up gradually. No tipping point yet.
But what about in the real world - out of the lab and into the ocean? We've been talking sea change as far away as the North Pole but there is also sea change closer to civilization. Just a short train ride east of New York City, David Conover is netting fish.
CONOVER: This is the winter flounder. This is the species that is highly susceptible to warming because—Long Island Sound is getting warmer, and this is a species that likes cold.
BRANCACCIO: And, now, of course I feel bad for all the flounders I've filleted over the years.
Conover is the Dean and director of the marine sciences research center at stony brook university. He's been studying how rising ocean temperatures are affecting marine life in Long Island Sound.
BRANCACCIO: All right, if we go way up the coast —cold water? Go south, where gonna find warmer oceans. But, here, in the Long Island Sound, you're right in the middle of that, aren't you?
CONOVER: We're right in the middle of a transition between typically warm water ocean and cold water ocean.
BRANCACCIO: Conover says the sound is an early warning system. One place to see the effects of ocean warming first. Cold water fish like the winter flounder will have trouble surviving in the sound as it warms up. Part of the reason is because of something called the temperature oxygen squeeze. When the water's warmer the fish get more active, which uses up vital oxygen. Without enough oxygen the fish can die off. And warmer waters can also bring disease. Consider not the lowly flounder but the exalted lobster.
CONOVER: This is the southernmost region where they're commercially harvested. And every summer when it gets warm, lobsters—in Long Island Sound turn up with a variety of diseases that appear to be linked to the ocean warming.
BRANCACCIO: Yeah. When you start talking lobster, you get people's attention. What do you mean? Somethin'hurtin' our lobsters?
CONOVER: When we had a massive die-off of lobsters in Long Island Sound, it got attention all over the country—because it was a very sudden outbreak of diseases that was linked to an unusually warm summer.
BRANCACCIO: And there are others who are—drawing a line from global temperatures that are warming and the temperatures of the ocean here?
CONOVER: Yes. There are—a variety of studies showing that things like diseases—that influence oysters have been migrating up the coast. There's a disease called Durmo that prior to—the 1980s was found only south of Chesapeake Bay. But during the 1990s, this disease has moved northward. Now, it extends all the way into Maine. And it influences—oysters, primarily.
BRANCACCIO: Oxygen depravation. Disease. And there's the acid. Did we mention the acid? A profound change in ocean chemistry is being caused by the biggest culprit in global warming - the carbon dioxide we create by burning fossil fuel.
CONOVER: That carbon dioxide dissolves in the ocean. And affects a chemical reaction—that increases the level of an acid called carbonic acid.
BRANCACCIO: In the ocean, carbonic acid eats through some marine life like vinegar through an eggshell. Coral get destroyed by this acidic water and coral are a big deal - whether or not you skin dive.
CONOVER: Coral are the—they are what we call—habitat engineers, ecological engineers. The structure that they're building provides habitat for many other organisms. The fish—sponges—lots of invertebrates, shrimps and crabs that all live in these coral reef systems. And without those systems, we're really changing the way the oceans function as an ecosystem.
BRANCACCIO: Scientists say by mid-century—with a no change, business as usual approach—there'll be no place on earth that can sustain coral. The situation evokes the battle against acid rain from a few decades ago. Pollution, especially from cars and power plants, made lakes in North American more acidic and a lot of fish died. It's worth noting that anti pollution policy improved those lakes markedly and mitigating acid rain is considered one of the great environmental success stories. But lakes weren't all that big in comparison.
CONOVER: Now, no one dreamed then that we would ever be thinking about acidity in a system as vast as the ocean. And the ocean is normally well-buffered. But CO2 is such a all-encompassing problem. It influences the oceans everywhere on the globe.
BRANCACCIO: So, the stakes are high, really? We may not know exactly the outcome. But the stakes are high when you talk about changing systems that large?
CONOVER: That's right. And it could be difficult to reverse. So, we're always a wary of experiments that are—for which the outcome is irreversible.
BRANCACCIO: You'd think with the stakes this high, we would've been studying this for years. But I'm hearin' from you the sense of urgency here has come relatively recently?
CONOVER: The urgency has come from the stronger and stronger scientific consensus that has emerged that in fact the warming that we are experiencing is due to human influences, and is occurring at rates—unlike what we've seen before. And certainly, the issue about CO2 and ocean acidification is—a very new urgency that we're dealing with.
BRANCACCIO: It's urgent because of the scale: some scientists worry a third to half of ocean species could be gone by the end of the century - we're talking mass extinction.
It's hard for people to fathom often. They look out at something as vast the Atlantic Ocean, and they say, there's something that we as puny humans could've done that would fundamentally change something that's so much bigger than us? But you're saying, as a scientist—no, no, no, we have.
CURRY: I am amazed. And the thing that brought this home to me was a trip I made to the arctic just a—a couple of months ago. I was—on a Norwegian icebreaker with some colleagues of mine. We went into the East Greenland Current. That's the very rapid current that transport ice and—and fresh water from the arctic, southward into the Atlantic along the east coast of Greenland.
There were people doing—measurements of the sea ice thickness all around us. There were people doing biology experiments. And we had a helicopter. And we went up in the helicopter—to—to go further inland to make measurements through the—through this sea ice. And from that perspective, from the perspective of being up in this helicopter and seeing just how enormous this river of—of ice and fresh water coming out of the arctic was, made me realize, this system is in—incredibly vast. And we humans have changed it in just really, you know, a century, or so. That's—that is incredible to me as a scientist.
BRANCACCIO: The changes include the fact that water expands when heated by global warming, a major reason for rising sea levels even now. Another change involves the actual color of the Polar Regions. Glaring white ice reflects a lot of the suns rays back out into space. When it's replaced with melted dark-blue Ocean, more heat is absorbed into the sea. Are we upsetting the planet's balance that much?
CURRY: The earth's climate system is huge. It's a huge beast and it's immovable. Or, seemingly immovable. It takes a lot to move it. It's like an enormous boulder that you try to push on. It takes a lot to push on it. But we've done it. We've actually pushed that boulder. And the thing is that, the climate system doesn't just bounce back anymore.
We've pushed it past a point where it can simply rebound.
BRANCACCIO: Right now some there is a tug of war going in Washington that will have a major effect on all of this. While the United States is just one country, it is an enormously influential country when it comes to both the production of greenhouse gases and efforts to cut them back. The incoming Obama administration has pledged to act vigorously to fight climate change.
OBAMA: The science is beyond dispute and the facts are clear. Sea levels are rising. Coastlines are shrinking. We've seen record drought, spreading famine and storms that are growing stronger with each passing hurricane season.
BRANCACCIO: The incoming administration has appointed a first-ever New Energy Czar. Carol Browner, who ran the Environmental Protection Agency under President Clinton, has said
BROWNER: This is a pivotal moment in our nation's history. The American people believe we can do better, and they are right. We can create jobs, curb greenhouse gas emissions, reduce our dependence on foreign oil, and help restore America's leadership around the world by shaping an environmentally sustainable world economy.
BRANCACCIO: Encouraging investments in clean energy is a key way forward. Browner—along with Obama himself—are boosters of what's called cap-and-trade, which let's cleaner factories and power plants sell the right to pollute to dirtier ones. The idea is to use the market to cut global warming gases. But critics point to Europe, where a cap-and-trade system has had disappointing results so far. There's a raging debate whether cap-and-trade is the right tool to keep us from hitting a tipping point.
The kind of tipping point that has just hit our experiment on the hot plate at Wood's Hole. The beaker is now completely ice free.
I'd say nine degrees.
CURRY: Nine degrees at eight minutes. Yeah, now it's starting to behave exactly the way we thought it would.
BRANCACCIO: There's no more ice to absorb the heat that we were applying to the system. 16 1/2.
CURRY: 16 1/2, wow, temperature's rising much more quickly, now.
BRANCACCIO: Which is about 65 Fahrenheit.
CURRY: Let's just wait a minute or two more. I think that the point will be very well established.
BRANCACCIO: Yes. It's 21 1/2. 24.
CURRY: We started off with a planet system with ice in it. Okay, and we just kept taking temperature and it stayed very steady. And then, what, at two 1/2 minutes, we turned on the heat. Okay, and it's began to rise a little—little bit.
BRANCACCIO: Little slow.
CURRY: But still very, very slowly. And then we said at seven minutes that the ice was completely disappeared. And after that, the temperature just kept going up and up and up at a pretty steady rate.
BRANCACCIO: With no more ice to buffer the heat the temperature of the water shoots up quickly. Ruth Curry is worried she witnessed that very same process during her trip to Greenland - disappearing ice causing the sea to heat up faster and faster...
Well, you start to add 'em up, all the different effects of global warming on the ocean, and they reinforce each other. I mean, you—you may have alterations in currents. You have melting of ice, changing the salinity of the oceans. You have—darker oceans absorbing more heat, as opposed to, lighter ice. I mean, the list starts to get long.
CURRY: The—pieces of the puzzle have been—begun to fit into place very well. Ten years ago, yes, there was a great deal of uncertainty. We weren't sure, but there was a tremendous focus on making the measurements that we needed to understand what was happening. And at the same time, we've also begun to cross these thresholds. So that the changes become more evident.
You have to make these measurements and continue to make—make these measurements, in order to discern changes that are going on. Because the climate system has a lot of natural variability in it. If you're going to get beyond that and see the big picture, see the forest through the trees, so to speak, you have to have a sustained measurement program.
BRANCACCIO: Measurement is one thing, but the real investment of resources will be finding ways to stop so much carbon dioxide and other greenhouse gases from getting into the air and into the ocean.
CURRY: We have to get our carbon dioxide emissions under control. Not only that, but we have to reduce the level of greenhouse gasses that are presently in the atmosphere.
So, that means not only moving to a—reduced carbon energy system, but that also means we need to find a way to mitigate what we've already done. In other words, remove carbon dioxide from the atmosphere.
BRANCACCIO: Yeah, I've been working on it in my basement. I haven't come up with it yet. But maybe somebody will.
CURRY: Yeah, well—I think that we're a long ways away from being there. We've already bought into several more decades of warming, just by what we've already done. But right now there's no—there's no plan in sight to curb emissions. So, in the same way that I described the climate system as a huge boulder, you know, this—this—this very—this system that's very difficult to move; so is the political/economic system of our planet.
BRANCACCIO: Will the new administration taking power in the coming days move to squarely take this on at a time of severe economic hardship and conflicts in the Middle East? Some have compared climate change to health care reform in the early nineties...that is clear and present threats that Washington policy makers never manage to crack.
CURRY: The problem is that we've already moved the climate system. And now the political system and the economic system, we have to move that in order to catch up with what we've done to the climate system.
BRANCACCIO: You can take a voyage into the future, to see what our world might look like in 50 years if action is not taken to stop a catastrophe in the high seas. A prominent ocean researcher will be your guide—buckle up, because it will be a wild ride. Check it out, only on our website.
And that's it for NOW. From where the Hudson River meets the Atlantic, I'm David Brancaccio. We'll see you next week.
Our Oceans: What Could Happen
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