PART 1: Severe storms in the Netherlands and a prolonged drought in Europe leading to unprecedented human migration — these are some of the scenarios laid out in “Imagining the Unthinkable,” a report recently issued to the U.S. Department of Defense on the possible worst-case effects of abrupt climate change. Host Steve Curwood talks with Peter Schwartz, one of the co-authors of the report, about the human consequences of such a scenario.
PART 2: Living on Earth continues the conversation on abrupt climate change, as host Steve Curwood talks with Leon Fuerth, former national security advisor to Vice President Al Gore, about the military and economic implications in the event of a rapid shift in global climate.
PART 3: National security and politics aside, the paleo-record of climate change shows strong evidence that an abrupt shift in climate could be headed our way. Host Steve Curwood talks with Daniel Schrag, professor of earth and planetary sciences at Harvard University, about the science behind abrupt climate change.
CURWOOD: From the Jennifer and Ted Stanley studios in Somerville, Massachusetts, welcome to Living on Earth. I’m Steve Curwood.
[MOVIE TRAILER MUSIC]
CURWOOD: For moviegoers across the country, Memorial Day marks the release of a film based on a concept of abrupt climate change. It’s Mother Nature gone wild, in the much-anticipated disaster flick, “The Day After Tomorrow.”
[SHRIEKS OF PANICKING PEOPLE]
MALE 1: [LIVE NEWSCAST] Lower Manhattan is literally inaccessible.
[ROAR OF TERRIFIED CROWD]
MALE 2: [LIVE NEWSCAST] There’s a wall of water coming towards New York City…
CURWOOD: Tornadoes dismantle Los Angeles, hail the size of grapefruit pummel Tokyo, and Manhattan freezes over in a single day as abrupt climate change makes its debut on the big screen.
MALE: Save as many as you can.
New York City gets hit hard in a global ecological catastrophe in the movie “The Day After Tomorrow.” (© and ™ 2003 Twentieth Century Fox)
CURWOOD: This Hollywood scenario may seem far-fetched, and the science of the flick is a bit wobbly. But a recent report to the Pentagon, based on an assessment from the National Academy of Sciences, points out abrupt climate change may be a very real threat to national and international security. “Imagining the Unthinkable,” as it’s called, outlines a worst-case-scenario in the event of a massive and abrupt shift in global climate – shifts that have happened in the relatively recent past.
One of the authors of the Pentagon report is Peter Schwartz, a future scenario planner. He frequently consults for the Defense Department. Peter Schwartz, welcome to Living on Earth.
SCHWARTZ: Thank you. Glad to be here.
CURWOOD: Now, your work makes you no stranger to the Defense Department, but – I have to ask you – you’ve been a consultant for Hollywood, right?
CURWOOD: What are some of the movie projects you’ve worked on?
SCHWARTZ: Well, the first one was a film called “War Games” back in 1981, then another one called “Sneakers,” both computer hacker movies. Then another one called “Deep Impact,” also a kind of worst case scenario, if you will, given what we’re going to talk about, of a comet coming toward the earth and how you might respond to it. I worked with a good friend Walter Parks on all three of those, and then with Steven Spielberg on “Minority Report.”
CURWOOD: And I can’t help but ask you then, what’s your take on this upcoming movie “The Day After Tomorrow”? And were you involved in its production in any way?
SCHWARTZ: I wasn’t, but I was asked to be. I chose not to be, mainly because this is pure entertainment. They weren’t really interested in making a realistic view. I think they were enamored of a number of the images that turn up in the movie. And that’s okay, this is pure entertainment.
CURWOOD: Now, you and some of your partners at your office recently drafted a report for the Pentagon entitled “Imagining the Unthinkable,” which is a worst case scenario for abrupt climate change. Why paint such a scenario in the first place? Why is climate change a military concern?
SCHWARTZ: Well, this begins, first of all, with the National Research Council report called “Abrupt Climate Change,” which looked at the possibilities for a scenario of abrupt climate change. The Pentagon, not surprisingly, read that report, the senior staff there, and said ‘we should consider whether this might have some national security implications.’ That’s what triggered our study.
And so it was an exercise in thinking the unthinkable. And from their point of view, the unthinkable means ‘could this happen soon, and could it be much more severe than most climatologists would say?’ So, if you think back to just only a few years ago, you might have wished that somebody had thought about what might happen if terrorists would send airplanes into tall buildings and buildings in Washington. It’s in that spirit. It isn’t trying to predict the future, it was trying to say ‘what if?’
CURWOOD: Now, there’s a lot of information in the 22 pages you put together here, Peter Schwartz. Can you give us the bullet points of what you found?
SCHWARTZ: Well, most significantly, it is this: what we’re saying is that, while it is unlikely, the most extreme case would be a scenario of fairly rapid warming in the near future – the next, say, decade or so – that would in turn trigger rapid cooling. What would happen is that the ice in the poles would begin to melt, as we’re already seeing some of. Glaciers would begin to retreat. Both of these would release fresh water into the North Atlantic. Increased precipitation associated with all of that might also lead to rivers producing more fresh water to the North Atlantic. That freshening of the North Atlantic, which we have been seeing, would then trigger a collapse of the Gulf Stream. It would move several thousand miles south. It would no longer bring warm water to the North Atlantic, warming, particularly, Europe, parts of the northeastern United States and Canada.
And that would be part of a larger shift of a similar nature in a number of parts of the world in the kind of heat balance mechanisms, particularly of the ocean currents. So that’s the kind of mechanism that triggers first warming and then cooling. The cooling would be something on the order of, over the northern hemisphere, of about five degrees or so over a decade or so. In fact, what we are describing is a picture of a world very similar to what happened 8,200 years ago, when the world’s temperature, particularly in the northern hemisphere, dropped a similar five degrees in roughly a decade, stayed down for a century, and came back up for a decade.
CURWOOD: Let me just ask you one more thing on the science. People talk in terms of global warming. How do you explain to them that you see a cooling here?
SCHWARTZ: Well, global warming is another possible scenario. We have a fair amount of uncertainty about what’s likely to happen. In fact what we could see – and as we emphasized, this is the worst case scenario – more likely is that you might see 50, 75 more years of warming that then could trigger a cooling. Or the cooling might never happen. I am personally of the mind that the more likely scenario that history tells us, is that we will get some sustained warming, and then we will experience abrupt cooling. The history of climate change is more often abrupt change, and it has frequently been large scale over very long periods of history.
CURWOOD: For the moment, let’s assume that the worst case scenario that you were asked to conjure up is happening. Could you lay out a timeline for us, what would be happening in the United States over the next few decades?
SCHWARTZ: Sure. The immediate effects would be you’d start to see more variability in the weather. You’d see more severe storms, you would see more torrential rainfall, you might see very short winters, very little snow, more rain. One of the impacts that is plausible, but hard to predict, would be a shift in the location of tornadoes. There is believed to be a belt of tornadoes off-shore in the south. You might see more coming on-shore. So those would be some of the kinds of symptoms of a kind of disruptive change under a way in the warming phase.
In the cooling phase what you would see is more severe winters, the kind of thing that you’re experiencing right now. But the more important thing you would see is a gradual diminishment of rainfall and then a movement into what we’re calling mega-droughts, i.e. they would probably be regional, in what we’ve thought, more likely, would be the southeast. But it could also be the Midwest or the far West as well. You know, again, think the 1930s here. This is similar to that. It’s not much worse, except for one important detail, which I’ll come back to in a moment. But – extended droughts over years, five, six, ten years even. And leading therefore to significant fall in reservoirs, in rivers, and so on.
And the thing that is importantly different in terms of its consequences this time, as compared to the 1930s, was that in the 1930s we still had substantial reserves of groundwater we could tap. And while the effects were severe, they were ameliorated in part by the groundwater. We no longer have those reserves. That water is all committed, or used up in some cases. That is, the big aquifers of America are now fully committed. So we don’t have spare capacity to deal with the rapid drop in rainfall. So that’s the kind of trajectory we’re talking about.
CURWOOD: In terms of conflict in the United States, what could happen with our neighbors? Like, what happens with Canada, for example?
SCHWARTZ: That’s a very good question. I can imagine a scenario where things got so bad in Canada that some people might want to head south, but frankly I don’t think the issues will be to the north. More likely they’ll be to the south. And we have two key bodies of water, namely the Colorado and the Rio Grande that, in effect, we share with Mexico. And we already have issues about managing both of those. And in this scenario that could be very severe and produce pressure for migration northward, on the one hand, and disruptions to the management of the water and conflicts over water that we share with Mexico.
But another one that we’ve already begun to experience some issues over is fishing rights in the Atlantic. We’ve already seen struggles between Spain, Portugal, and France over fishing rights there, ourselves with respect to the Europeans and the Canadians in the Grand Banks. This could be a really significant issue, because, of course, the fish move with changing temperature of the seas as well. When the ecosystems of the seas change, the locations of the fish change. And we have now become dependent on various fish populations in both sides of the Atlantic. And you can imagine conflicts over access to fishing.
CURWOOD: Now, what are some of the geopolitical things that you forecast here in your scenario? What happens to people and politics under the scenario that you paint?
SCHWARTZ: Well, we see, for example – right now, an example of something that is the kind of consequence we might have to deal with and the kid of political issues – the unraveling of Haiti, and should we intervene or not. One of the possible disruptions is to water supplies in the Caribbean and Central America. The United States has already several times been hit by waves of refugees from that part of the world. And it is not at all implausible that we could be doing better, and others worse, and we could be hit – immediately in our environs, from the Caribbean, Central America, maybe even Mexico, but especially Central America and the Caribbean – with very large numbers of people headed our way. How do we cope with it? Should we intervene in advance? Should we send them water supplies rather than let them come here? There’s all kinds of important political questions, technical questions and so on that would have to be resolved. And we’re suggesting thinking about those kinds of things in advance, rather than having to improvise in the moment.
CURWOOD: Now, you write also that a possible reaction here in this country to abrupt climate change might be to turn inward, committing our resources to feeding our own population, shoring up our borders and managing increasing global tension. But how does the United States manage this global tension if at the same time it’s closing itself off to the rest of the world? I mean, wouldn’t this create even more tension?
SCHWARTZ: You’re exactly right. I mean, that is the heart of the issue. That’s part of why we’re warning of this. We have an instinct to kind of stay at home, as it were. And under these circumstances you can imagine much of the population, particularly if there are significant disruptions and high costs domestically, saying, you know, let’s take care of our own. Meanwhile you can imagine a political leadership looking around the world and saying, God, there are really terrible things, we’ve got to be helpful. And if we don’t, that will still some home to us eventually one way or the other, and we better deal with it over there than over here. Now caught between a populace reluctant to intervene and the necessity of intervention. And we’ve been there before. And that kind of situation, I think, is not at all implausible in this circumstance.
CURWOOD: What happens to your report now that you’ve handed your findings over to the Pentagon?
SCHWARTZ: Well, unfortunately this has gotten a lot of negative publicity, in the sense that particularly The London Observer both implied that the Pentagon tried to suppress the report on the one hand, and secondly that they exaggerated our conclusions, made it a prediction rather than a worst case scenario. And then turned it around and said, well, see, this proves that the Bush administration is wrong. So, in fact, the likelihood is that very little will happen as a result of it. Had it been able to proceed in a more appropriate fashion, it would have been considered along with many other possible scenarios regularly considered by the office of net assessments and the Secretary of Defense’s office – that they consider as the routine part of their thinking in the long run.
CURWOOD: So, let me see if I understand this right. Because the public and the press has kicked this around in perhaps, from your perspective, an overly dramatic fashion, it means that the Pentagon can’t think about this at all?
SCHWARTZ: It means that this kind of thing gets suppressed for a while. It will come back up again. But it means that this is a taboo topic because you have a meeting about it, and it leaks out to the press again, and it just keeps the storm going, if you know what I mean.
CURWOOD: Peter Schwartz is a future scenario planner and chairman of the consulting firm Global Business Network, part of the Monitor Group. Peter, thanks for speaking with me today.
SCHWARTZ: My pleasure.
CURWOOD: Coming up, we’ll continue the climate change conversation with two perspectives on the science and security implications of global warming. We’ll be back in a minute, stay tuned. I’m Steve Curwood, and you’re listening to NPR’s Living on Earth.
[MUSIC: Pan American "Starts Friday" PAN AMERICAN (Kranky - 1998)]
CURWOOD: Welcome back to Living on Earth, I’m Steve Curwood. We’ve been talking about abrupt climate change, and “Imagining the Unthinkable,” as a recent report to the Pentagon is titled. This document outlines a worst-case scenario of abrupt climate change that would cause massive disruptions in agriculture, the economy, and international diplomacy.
So far, the Pentagon has had no public comment on the report of its consultants. But soon climate change may be a hot topic on the national security agenda. With me to talk about the security implications of abrupt climate change is Leon Fuerth, Professor of International Affairs at George Washington University, and the former national security advisor for Vice President Al Gore. Leon Fuerth, welcome.
FUERTH: Thank you.
CURWOOD: Well, we’ve heard from a consultant to the Pentagon that an abrupt shift in climate could turn out to be a critical issue of national security if it should occur. I’m wondering if you could tell me from your own experience, working as a national security advisor here in the United States, Leon Fuerth, what do you think would happen strategically around the world? What changes, what imbalances in strategic alliances would happen, do you think?
FUERTH: I think what would happen is that the world as you knew it, organization as you knew it, relationships among states as you understood them, the rules of economics as you had understood them would all be shifting. I mean, our territory would remain inviolable, but our business may go to hell. At the level of strategic alignments, one of the continents that would experience the greatest dislocation would be western Europe, where the place would become much, much colder, possibly with the effect of severely damaging the economy of the northern tier of countries and causing a lot of people to try to move south, and creating tremendous internal migration problems for the European Union at the time.
CURWOOD: If there is a country in the world that the United States has a lot of business to do with in the diplomatic sense, in the world power sense, it has to be China. The scenario says that China’s going to have pretty serious water problems, and that means food problems. It’s a quarter of the world’s people, and today they’re rich and technologically savvy. What might happen between the United States and China in such a world?
FUERTH: Interesting question. One of the determinants is do we continue to need to borrow half a trillion dollars a year to finance the debt of the federal government of the United States, most of which has been coming from China. And it works out in a giddy sort of way. They lend to us so that we can buy their products.
Now if, let’s say, two administrations from now, all of a sudden the climate patterns in China begin to shift drastically, it’s natural to believe that trade, economy, and other issues are going to also be disturbed.
So, one of the things I think the United States should do in its own interest is to make itself less dependent on the scale of borrowing than we have been. Because if any of our creditors, for any reason, finds themselves unwilling or unable to continue to lend to us at this rate, then that house of cards can come down.
CURWOOD: So, Leon Fuerth, if you were the national security advisor today, what steps would you advise that the United States take to deal with the possibility of such a climate scenario?
FUERTH: First of all, I think we need a major effort to acquire better modeling in order to be able to calculate as accurately as possible, and in real time, what some of the effects might be. I would begin having people work out planning scenarios, including some of the social, economic, and political consequences in parts of the world where, let’s say, the agricultural cycle is disturbed. Better to have people playing these mind games over what might occur while we still have time to think about action than to wait until the evidence is on hand that we’re in the middle of it.
CURWOOD: What do you suppose is going on in the Pentagon now and in the Bush administration in the aftermath of this report?
FUERTH: Not much. I mean, what’s interesting about this is that this is not like Orson Wells “War of the Worlds,” where what you had was a fantasy that was put out there, which inadvertently frightened the public. What you have here is a response to a request from the Department of Defense for a scenario – imagine something. But what they did was imagine a thing on the basis of an event they considered quite possible. And so what it carries is a message, which is: it’s time to get real about this while we still have the luxury of time and resources and allies to work the problem.
CURWOOD: Leon Fuerth is professor of International Affairs at George Washington University, and the former national security advisor for Vice President Al Gore. Thanks for taking this time with me today.
FUERTH: Thank you.
CURWOOD: We’ve been talking about the economic and political consequences of abrupt climate change, in light of a recent report to the Pentagon called “Imagining the Unthinkable.” The authors stress that the scenario they paint “pushes the boundaries of current research on climate change.” With me to talk about what we do know within the boundaries of climate science today is Daniel Schrag, professor of earth and planetary sciences at Harvard University. Hello, sir.
SCHRAG: Good day.
CURWOOD: What should you as a scientist – let’s say the Defense Department calls you up and says, Professor Schrag, as part of our national security assessment, we are on the lookout for signs of abrupt climate change. What do you look for?
SCHRAG: There are a few possible modes of abrupt climate change that we’ve seen in the past, in the geologic past, that we could look for in the future. The most obvious one would be an instability in the large ice sheets on Greenland or Antarctica. So, if the West Antarctic ice sheet or if the Greenland ice sheet started to exhibit some very unusual behavior, and we thought that a large amount of ice might slide off the continent and into the ocean, this could cause a very abrupt rise in sea level. And would damage coastal cities around the world, devastating world economies.
CURWOOD: Hm, hmm. Now, Professor Schrag, the Defense Department is worried about this. They tend to have a short-term view of things. The effects that you’ve been talking about so far seem to be decades away. I’m confused – why is the Defense Department so concerned, apparently over the short-term here?
SCHRAG: Well, what I’m talking about may take years to decades to actually happen, and no one knows exactly when these sorts of things can occur, but one shouldn’t think that these effects are just decades away. The truth is no one knows. We are already experiencing a world that is substantially warming because of human activities. We know this from the melting of ice in the tropics up at high altitudes, Kilimanjaro and in the Andes, and a lot of other pieces of evidence that tell us global warming is happening now.
CURWOOD: Now why does melting of ice in the tropics indicate global warming?
SCHRAG: Well, this is a really powerful piece of evidence that climate change is happening now. The middle of the troposphere, the middle of the atmosphere near the equator, is a very stable region of the atmosphere. There’s very little weather there, there’s very little variability. And so, as a result, if one starts to see warming there you know that it’s a global signal, because there’s very little variability normally.
In the case of these tropical glaciers, Lonny Thompson, from Ohio State University, has shown that these glaciers are melting for the first time in thousands of years. So that proves that it’s not a 100-year cycle, or a 500-year cycle. This is truly an extraordinary event coincident with the enormous rise in carbon dioxide from burning fossil fuels. And to me, that’s the most compelling evidence that climate change is happening now.
Now, when we cross certain thresholds that lead to abrupt change, no one has any idea. We don’t think that Greenland or West Antarctica are going to melt and drop into the sea in the next 10 years. On the other hand, if they suddenly crossed an instability and started to collapse over a period of a few years, it would be too late to do anything about it. And no one knows exactly when that happens. So to me it makes sense that the Pentagon is planning for all sorts of possibilities, just like an insurance company.
CURWOOD: What kind of shape is the West Antarctic ice sheet in right now?
SCHRAG: Well, it’s hotly debated. Some scientists think that the West Antarctic ice sheet is so large and massive that it’s insulated from all changes, and that it takes thousands of years for the ice sheet to adjust to the warming that we’re experiencing now. Other scientists think that there are mechanisms that we don’t understand very well, whereby the ice sheet can actually move and adjust very rapidly. And if that’s correct then we are in danger of that amount of ice falling into the ocean. And that amount of ice represents a substantial amount of sea level change.
CURWOOD: On the order of?
SCHRAG: On the order of six meters or so.
CURWOOD: 18 feet of more water.
SCHRAG: And that would pretty much wipe out every coastal city in the U.S.
CURWOOD: And how soon could that happen?
SCHRAG: Well, if it went in over a period of even a hundred years it would mean devastation. You can’t even begin to calculate the amount of damage that that would do to the U.S. economy. And to the global economy. And if it went faster than that, which is possible, we’d really be in trouble. I think that really gets to one of the points about climate change. We’re doing an experiment on the earth that hasn’t been done in millions of years, and no one knows what’s going to happen. And if we suddenly decide that a disaster’s going to befall us, we may not be able to turn back the clock. Because the system has so much momentum, and is so powerful, we can’t just assume that we can fix it.
CURWOOD: You folks who look at the changing climate often use computers to model. In fact that seems to be the basis of a lot of the predictions of the warming that’s coming. How well do these models work when you look back at these other changes thousands and millions of years ago? How well do these computers predict something we already know the answer to?
SCHRAG: That’s a very good question. It turns out that the answer is that sometimes they work very well, and sometimes they don’t work very well. And of course a model is most interesting when it doesn’t work well, because it tells us that something’s missing. Remember that the models are only as good as the physics that we put into the model. And therefore the models reflect our understanding of the climate system based on modern observations, primarily over the last 50 years or so. Now, we’re entering into a mode of climate with high atmospheric carbon dioxide that we haven’t been in for tens of millions of years. So nobody has the right set of observations to completely describe the climate system in this mode.
What’s interesting is about 50 million years ago, the earth was very warm. We think that carbon dioxide was high. We don’t know exactly how high, we think maybe 1,000 to 3,000 parts per million, which is not that far off from where we’re going to be 100 to 200 years from now. Now, at that time there were crocodiles living up in Greenland, there were palm trees in Wyoming. Palm trees can never have cold winters, and there were palm trees thriving in Wyoming, where today it gets very cold. Antarctica was a pine forest. Sea level was about 150 meters high than today. It was a completely different world. And the question is, can these models produce it? And when you try to put high carbon dioxide in the models and let them try to simulate the climate, it turns out they don’t do a very good job. They actually don’t get the world warm enough. There’s something missing in the models that is a positive feedback that amplifies the effect of the carbon dioxide. But if that effect kicks in, the warming could be much more severe than the models are predicting.
CURWOOD: Yeah, I was going to say, you’re starting to scare me here.
SCHRAG: Well, we should be scared.
CURWOOD: You’re saying the models that are predicting this rather large shift don’t predict these biggest shifts from the past. Therefore, we’re missing something here.
SCHRAG: You know, we’ve been hearing in the debate about climate change in the public a lot of rhetoric that says because the climate scientists aren’t certain, we should wait and not do anything about it. For me it’s exactly the opposite. It’s our lack of certainty, which is why we should do something now. Because the answer could be much worse than we expect. Climate change could be much more severe than anyone thinks.
CURWOOD: This summer there’s going to be a movie out of Hollywood. I think it’s called “The Day After Tomorrow.” It paints an apocalyptic scene of, actually, the northeastern United States pretty much freezing over.
SCHRAG: I know. I get a lot of pleasure from looking at the preview. I show it in some of my talks. Unfortunately, I think that’s probably a very unlikely scenario. I think the idea comes from the idea that the Gulf Stream will somehow collapse when the thermohaline circulation of the Atlantic stops. And therefore this will lead to an ice age and everything will freeze. The truth of the matter is that if the thermohaline circulation stops, it will affect a region around Britain and Scotland, but will probably not affect New York much at all. The movie was by the maker of “Independence Day,” and I think after destroying Washington, D.C., he wanted to destroy New York City, and he found a way to do it.
CURWOOD: Why now all this attention to the question of abrupt climate change? The Greenland ice core samples that you told us about have been around for a long time, demonstrating that it didn’t take more than a few decades to change a lot of temperature. And yet today, folks like the Defense Department, folks in Hollywood, are suddenly paying attention to the question of abrupt climate change. Why is that happening?
SCHRAG: I think there are powerful forces in our society that have a lot of economic stake in our current energy technology, and are resistant to change. And therefore have promoted the idea that this was just a theory, that climate change was just an idea that scientists had that they weren’t sure about, and discouraged action on this front.
And I think a variety of different sectors of our society are beginning to wake up to the fact that we can’t just put our head in the sand and hope that it goes away. We know that climate change is a serious risk. The probability of it being dramatic is very high, probably greater than 50 percent. And yet we’re willing to spend almost nothing to protect ourselves. We need to buy at least some insurance. And to me, the minimum insurance policy is that we actually should have the technological capacity to do something about it. At the very least, we should be able to change our behavior if we want to. Right now we can’t even do that.
CURWOOD: Daniel Schrag is a professor of Earth and Planetary Sciences at Harvard. Thanks for taking this time with me today.
SCHRAG: Thank you.
[MUSIC: Yulara "Horizon" COSMIC TREE (Higher Octave Music - 1998)]
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