Interview: Spencer R. Weart

If AI Gore's An Inconvenient Truth was the catalyst that turned the tide on pubic engagement with the issue of climate change, then Spencer Weart's The Discovery of Global Warming is what climate scientists pointed to when an alarmed public started looking for the backsto-ry. Weart, a physicist by training, switched gears in 1971 by enrolling in the history _I department at the University of California, ES Berkeley. His curiosity led him to start dig-y ging into the fragmented history of climate 3 science in the mid-1980s.

Completed in 2001 and named in reference to the Intergovernmental Panel on Climate Change's Third Assessment Report, which ushered scientific consensus on the existence of global warming that same year, The Discovery of Global Warming now enjoys a substantial popular and scientific status that rivals Gore's film in its ability to summarize basic science and foster awareness; it also grapples with the political and societal subtexts that permitted the science to coalesce.

Weart has made a habit of studying scientific ideas so vast, complex, and consequential that they more readily lend themselves to emotional interpretation than technical evaluation. In Nuclear Fear: A History of Images, originally published in 1989 (a revised edition is in progress), he argued that histrionic symbolism has obscured genuine scientific literacy about nuclear energy.

For more than 30 years, he has directed the Center for the History of Physics at the American Institute of Physics and has built a career and a reputation on sorting out the rational from the irrational in matters of public scientific understanding.

The Bulletin talked to Weart about political and environmental gamesmanship and post-apocalyptic fantasies, and their impacts on our prospects for a peaceful, sustainable world.

BAS: You often make the comparison between preparing to deal with climate change and insuring your house for fire damage. What do you mean by that?

WEART: The problem with climate change is that it wasn't anything, at least until very recently, that anyone could observe. Some people say, Why should we pay a lot of money to deal with that when it's just a hypothetical risk? The obvious answer is, well, you buy insurance. It's a rhetorical device to make clear why it's valuable to take action against something that is quite properly seen by scientists as only a probability, not a certainty.

BAS: Nuclear terrorism is not a certainty, not even a probability, according to some experts. So why is the public more concerned with that than with climate change?

WEART: People do not respond rationally to risk, and there are lots of studies about why they get it wrong. People are more afraid of things that they think may happen to them very soon, of course, and global warming sounds like a problem for the next generation and maybe more for polar bears and Pacific Islanders than for you and me. They are also more afraid of things they think they can't control, like “bad guys”–the language shows how childish this is–than things they think they can control, like their driving or smoking or energy use. And we are scared by the strange and unknown, so nuclear terrorism seems much more scary than terrorists with chemicals or germs, which is actually a lot more worrisome to experts.

BAS: As a physicist, how did you get interested in climate change?

WEART: I began doing research on the history of climate change simply as an intellectual problem. Geophysics was very different from physics because of the structure of the field, the wide variety of different specialties, and the difficulty of understanding it. It's an observational field rather than an experimental field, and I thought it was just interesting to study how people arrived at tentative conclusions, in this case necessarily probabilistic conclusions. It was very, very different from the kind of history of physics that I'd been doing.

I was as surprised as anyone else when it turned out to be such an important question for our civilization. I had not expected when I began the work around 1986–1987 that by the time I finished, it would be a major political issue.

BAS: What is the difference in expectations when performing observational science as opposed to experimental science?

WEART: The big problem for scientists is coming to a reliable conclusion, and not to be fooled by some plausible evidence. In the fields that historians of science have studied most, like physics and genetics, you can check by seeing if new experiments do what you'd expect, and also if the theory fits together in a nice, simple way. Climate change has none of that. And it's even more interesting because you have to fit together so many different things, from solar physics to smog chemistry to soil microbiology. So you have to figure out what to believe, or who to believe, in fields that you know nothing about. That makes for a fascinating intellectual history.

BAS: In The Discovery of Global Warming you draw out the parallel genesis of climate research and radiation research related to Cold War and military demands. How did the two start out in tandem?

WEART: It isn't just the history of climate or radiation research, it's everything. It's now well understood among historians of science that half of everything that happened in science after 1945 was related to and funded by Cold War mechanisms.

BAS: How did the atomic bombings of Hiroshima and Nagasaki affect climate research?

WEART: One of the important points I came upon while working on Nuclear Fear, which is particularly applicable to the climate, is that the advent of the atomic bomb, more than anything else, convinced people that human beings were now in a position to change the entire global environment. It was Rachel Carson who said it was fallout that taught her about the problems that humans caused to the environment. That idea opened the door for people to consider that we might be able to change the climate itself.

BAS: So without nuclear weapons we wouldn't have a general understanding of climate change?

WEART: Without nuclear weapons it would have been much more difficult for people to grasp the fact that human technology has reached a state where we are a geophysical force. Already in the 1920s there were a few people who understood that the human output of materials was on a geophysical scale–but if it hadn't been for the advent of nuclear weapons, it would have been much harder for people to grasp. There were other factors, too. For example, the ozone hole also helped to convince people that human activities had reached a scale where we were a major force in the geophysical system.

BAS: What made the critical difference between the few and the many accepting that fact?

WEART: That's a difficult question. There were those involved in climate modeling, who as early as the 1970s began to say that sometime around the year 2000, the climate signal is going to emerge from the north. They were a generation ahead of their time, simply because they were running their own computer models.

Now, people who were not computer modelers, and who weren't running the models themselves, they had a hard time trusting this; it wasn't their own work. This is a big problem with climate change in general. Greenhouse warming is not scientifically obvious. There are certain natural phenomena, such as the trade winds and the existence of red giant stars, that a person cannot simply prove to exist by waving his hands. You can't derive the trade winds from complex sets of equations. You can't derive the existence of red giant suns just by sitting down with a few pages of the analysis. Global warming, as it happens, is one of those things.

BAS: So technology is the intermediary?

WEART: Well, computers in this case. If we didn't have computers we would have evidence from ice cores and so on that carbon dioxide correlates with temperature, but we would be very hard put to say exactly what will happen.

BAS: While researching and writing The Discovery of Global Warming, what did you learn about the early climate science community?

WEART: Intellectually, the thing that surprised me the most was to find out how cut off these scientists were from each other. I would be reading an article, and I'd think, doesn't this person realize that this was discovered 10 years ago? No, this person doesn't realize it, because he was working in a somewhat different field!

There were cases of someone understanding something very important about global warming in the 1930s, and other people didn't catch onto it until the 1960s. The field was so broken up into different specialties. Now, that has been solved by the Intergovernmental Panel on Climate Change, but it was quite amazing to me to find out how poor the communications were among scientists of different specialties up until the 1980s and 1990s.

BAS: Was there an off-line dialogue among any of the scientists at that time in the same way that it existed for scientists who worked on nuclear weapons in the early days?

WEART: This developed over time. In the very early days, so few people worked on global warming that they hardly knew of each other's existence. As time went on, the communities got larger, the communications got tighter, and if you talk about, for example, the current climate modeling community, most of what goes on between these people is very intense exchanges, not only of ideas and thoughts and arguments, but vast flows of data–terabytes of data flow back and forth between these people and hardly show up in the scientific literature.

BAS: Do computer models play too large a role in climate change research?

WEART: People tend to have a limited trust of computer models, and quite rightly so. The computer models are not completely trustworthy, as the modelers themselves are aware. Unfortunately, we have no other choice. It would be difficult to make predictions, almost impossible, without computer models, so we simply have to take the real scientific risk that the models are far from perfect.

For example, the models are deliberately designed to be stable. You can't do anything with an unstable model, and therefore by design they're incapable of showing any horrible, abrupt, very unlikely, but totally catastrophic thing that might happen. They're just not able to show those things.

Then there's the public relations risk. People would like to have it all written down, and if you're an engineer, you'd like to have the basic equations that prove that it's going to get three degrees warmer. Models just can't provide that, so people are suspicious.

BAS: Let's switch gears for a second and talk about Nuclear Fear and public perception of nuclear war. Do you think the U.S. public has been made to believe that nuclear war is winnable?

WEART: Oh, no, nobody believes nuclear war is winnable. The generals don't believe it, there's nobody who believes that nuclear war is winnable. The insane logic of nuclear deterrence is that you have to act as if you're willing to do it–as if you think that you're going to win–in order to have a proper deterrent effect. Yet, presidents Richard Nixon and Ronald Reagan, the big warmongers, were completely terrified of nuclear war.

BAS: But there's been a resurgence in the idea that there's a utility to certain nuclear weapons.

WEART: Well, the main change that took place with the end of the Cold War was the shift from the idea of large-scale nuclear war as the Armageddon, the apocalypse, to the targeted nuclear bomb, the missile launched by Iraq, or Iran, or North Korea, or the single explosive device carried by a terrorist. So we're now talking about something very different from the end of the world. We're now talking about an attack on a single city.

It was Rachel Carson who said it was fallout that taught her about the problems that humans caused to the environment. That idea opened the door for people to consider that we might be able to change the climate itself.

BAS: Does the public make that wide distinction?

WEART: Sure, the public is no longer very interested in or concerned with large-scale nuclear war. About the only condition that nuclear war has, at least for the younger generation, is it would set the stage for some kind of post-apocalyptic, Mad Max computer game with the hero fighting against the mutant monsters or the banded motorcycle gangs, or whatever. Fighting a nuclear war is no longer something for which we have popular books and movies and so on. The large-scale apocalypse is just a kind of set piece that allows you then to have these post-apocalyptic fantasies.

BAS: You talk a lot about the cultural, artistic interpretations of nuclear weapons, but how do the actions and policies of governments play into the public's nuclear fear?

WEART: Well, government policy is itself built around imagery. Nuclear weapons, at least since the advent of the hydrogen bomb, are not meant to be used, they are meant to serve as a deterrent–that is to say as an image, as something that exerts psychological effect. In fact, the Hiroshima bomb itself was meant, although it had physical effects, as a psychological weapon.

This has become ever more true in the context of North Korea. Pyongyang makes this device, and the device sort of goes poof! And we see that it's not the real bomb. What's frightening is the idea of North Korea having a bomb; the idea of terrorists getting the bomb.

The imagery of nuclear explosions is a cultural obsession unlike any other, because it ties in with so many deep images, mutant monsters, suicidal madmen, the apocalypse, etc. So it distorts our thinking. Let me tell you a story. On 9/11,1 was backpacking in Colorado, and I didn't hear about the fall of the Twin Towers until four days later. As somebody who had spent those days looking at mountains and not television, I thought everyone had gone mad with fear. What was so ultimate about this particular event?

Eventually, I realized that the attacks had demonstrated that terrorists might be both able and willing to do what people were really afraid of, a nuclear attack, and we have seen plenty of television dramas and so forth since to confirm this is a big fear. An example of the effect of nuclear fear on policy is the billions of dollars wasted on systems to shoot down missiles, systems that don't work, built to counter missiles that don't even exist.

BAS: Do you think that's how the Bush administration sees missile defense? Or the way Reagan saw SDI?

WEART: These people aren't stupid. They might hope that missile defense could have an actual physical effect, but they never expected the Russians to launch 10,000 missiles at us. The whole idea behind missile defense was to insert a psychological effect to prevent the Russians from doing it, or even to force them to back off from the Cold War. It was known that SDI wouldn't work, and it didn't work, but nevertheless people spent many billions of dollars on it. It was the expenditure of billions of dollars that had the most important effect, rather than any actual devices that were produced.

BAS: Why do you think fear has so much currency that an initiative like missile defense can have such a huge political impact despite its technical impotence?

WEART: People will always be afraid of something. And we need enemies. Anthropologists tell us we need an “out-group” to consolidate our “ingroup.” Psychologists tell me I need “bad guys” to contrast with my own goodness. After the fall of Communism, we thrashed around attacking cocaine users, child molesters, and whatnot, but found foreigners work a lot better. And in Iran and North Korea, there are foreign-looking and strangely behaving tyrants who threaten to build monstrous weapons. That's nice for politicians who would like to point to enemies that they can defend us against, if we'll give them more power, which is what politicians want. These are all very strong forces.

BAS: Is there any other way that nations can have that same psychological effect, without having nuclear weapons?

WEART: At present, nuclear weapons have a unique status. I was surprised by the enormous resonances and imagery that revolve around them. And I was surprised when I looked at climate change. I was expecting to find profound interest in public imagery, and it wasn't there. Climate change imagery is more typical: polar bears, or Alaskan natives, or floods and other prosaic images that have very little psychological resonance.

BAS: Have you thought about how nuclear fear will play into addressing climate change, particularly regarding nuclear energy?

WEART: Yes, everyone understands that nuclear fear has held back the deployment of nuclear reactors. One of the main reasons that nuclear reactors have been uneconomical is because they have been so heavily regulated. Fears among investors and so forth of future regulation and losses because of accidents will continue to play a role in retarding their deployment. We now recognize that some of these fears have been irrational, or let us say they have been irrational in comparison with the other risks that we face. Although many people will be reluctant to admit it, it's been a tragic mistake to build so many coal-fired power plants where nuclear reactors could have been built instead. As was earlier suspected, small particulates from coal cause very high levels of mortality and morbidity, which we are not likely to get from nuclear reactors. And this is entirely aside from greenhouse gas emissions.

BAS: How do you convince people who still have a very large fear of nuclear energy to appreciate the adverse effects of the energy path we've chosen thus far?

WEART: Ask them to enumerate the risks of nuclear reactors and set them alongside the risks of coal-fired plants. One thing that they will come up with quite properly is that reactors raise the risk of proliferation, which is connected with our fears of terrorism. So that gets to the larger issue of whether to deal with terrorism as an overwhelming fear that all of us must concentrate our attention on, or whether terrorism is not something on which all of our political energy should be concentrated.

BAS: What image would communicate the real risks of nuclear war?

WEART: Well, that's not hard. We have photographs of it.

BAS: Sure, but historical images don't necessarily resonate with people today. They see them as relics.

WEART: True, true. Perhaps just as well. I don't think you need to convince people that having a nuclear bomb go up is a bad idea. You say “nuclear bomb” and everybody immediately thinks of the end of the world.

BAS: So you think the public is aware of the horror?

WEART: Most people are bombarded with so many images that none of them can have a very strong effect. Most of them are now perceived ironically or through referencing.

You don't need to convince people that exploding nuclear bombs is a bad thing. That's taken for granted. The problem is to convince them that the way to avoid this is by having fewer nuclear weapons around. That seems to be a harder thing to convince people of.

BAS: How does understanding nuclear imagery help us move forward toward a world free of nuclear weapons?

WEART: Civilization advances as people come to terms with the unconscious; Freud was right about that. As we understand which part of our worries is irrational, and which is nothing but infantile imagery and emotional connections, we can do a better job of allocating our resources to deal rationally with the various problems we face. When the day comes that we can laugh at the very idea of a national leader shooting off a nuclear bomb, we will start to be free.

Supplementary Material

Climate Change 2001: Synthesis Report: Summary for Policy Makers