These are just some of the reasons why David King wrote in Science in 2004, "Climate change is the most severe problem that we are facing today—more serious even than the threat of terrorism." King's comment raised hackles in Washington and led a top press aide to Tony Blair to try to muzzle him. But the science adviser tells me he "absolutely" stands by his statement. By no means does King underestimate terrorism; advising the British government on that threat, he says, "is a very important part of my job." But the hazards presented by climate change are so severe and far-reaching that, in his view, they overshadow not only every other environmental threat but every other threat, period.
"Take India," King says. "Their monsoon is a fact of life that they have developed their agricultural economy around. If the monsoon is down by 10 percent one year, they have massive losses of crops. If it's 10 percent over, they have massive flood problems. [If climate change ends up] switching off the monsoon in India, or even changing it outside those limits, it would lead to massive global economic de-stabilization. The kind of situation we need to avoid creating is one where populations are so de-stabilized—Bangladesh being flooded, India no food—that they're all seeking alternative habitats. These, in our globalized economy, would be very difficult for all of us to manage."
The worst scenarios of global warming might still be avoided, scientists say, if humanity reduces its greenhouse-gas emissions dramatically, and very soon. The I.P.C.C. has estimated that emissions must fall to 60 percent below 1990 levels before 2050, over a period when global population is expected to increase by 37 percent and per-capita energy consumption will surely rise as billions of people in Asia, Africa, and South America strive to ascend from poverty.
Yet even if such a reduction were achieved, a significant rise in sea levels may be unavoidable. "It's getting harder and harder to say we'll avoid a three-foot sea-level rise, though it won't necessarily happen in this century," says Michael Oppenheimer, a professor of geosciences and international affairs at Princeton. Oppenheimer's pessimism is rooted in the lag effects of the climate system: oceans store heat for a century or longer before releasing it; carbon dioxide remains in the atmosphere for decades or longer before dissipating.
According to King, even if humanity were to stop emitting carbon dioxide today, "temperatures will keep rising and all the impacts will keep changing for about 25 years."
The upshot is that it has become too late to prevent climate change; we can only adapt to it. This unhappy fact is not well understood by the general public; advocates downplay it, perhaps for fear of fostering a paralyzing despair. But there is no getting around it: because humanity waited so long to take decisive action, we are now stuck with a certain amount of global warming and the climate changes it will bring—rising seas, fiercer heat, deeper droughts, stronger storms. The World Health Organization estimates that climate change is already helping to kill 150,000 people a year, mainly in Africa and Asia. That number is bound to rise as global warming intensifies in the years ahead.
The inevitability of global warming does not mean we should not act, King emphasizes: "The first message to our political leaders is, action is required. Whether or not we get global agreement to reduce emissions, we all need to adapt to the impacts that are in the pipeline." That means doing all the things that were not done in New Orleans: building sound levees and seawalls, restoring coastal wetlands (which act like speed bumps to weaken hurricanes' storm surges), strengthening emergency-preparedness networks and health-care systems, and much more.
Beyond this crucial first step—which most governments worldwide have yet to consider—humanity can cushion the severity of future global warming by limiting greenhouse-gas emissions. Hansen says we must stabilize emissions—which currently are rising 2 percent a year—by 2015, and then reduce them. Avoiding Dangerous Climate Change, a book based on a scientific conference convened by Tony Blair before the G-8 summit, estimates that we may have until 2025 to peak and reduce.
The goal is to stop global warming before it crosses tipping points and attains unstoppable momentum from "positive feedbacks." For example, should the Greenland ice sheet melt, white ice—which reflects sunlight back into space—would be replaced by dark water, which absorbs sunlight and drives further warming.
Positive feedbacks can trigger the kind of abrupt, irreversible climate changes that scientists call "nonlinear." Once again, Hurricane Katrina provides a sobering preview of what that means. "Hurricanes are the mother of all nonlinear events, because small changes in initial conditions can lead to enormous changes in outcomes," says Hans Joachim Schellnhuber, the director of the Potsdam Institute for Climate Impact Research and the former chief environmental adviser to the German government. "A few percent increase in a hurricane's wind speed can double its destructiveness under certain circumstances."
Although scientists apply the neutral term "climate change" to all of these phenomena, "climate chaos" better conveys the abrupt, interconnected, wide-ranging consequences that lie in store. "It's a very appropriate term for the layperson," says Schellnhuber, a physicist who specializes in chaos theory. "I keep telling politicians that I'm not so concerned about a gradual climate change that may force farmers in Great Britain to plant different crops. I'm worried about triggering positive feedbacks that, in the worst case, could kick off some type of runaway greenhouse dynamics."
Among the reasons climate change is a bigger problem than terrorism, David King tells me, is that the problem is rooted in humanity's burning of oil, coal, and natural gas, "and people don't want to let that go." Which is understandable. These carbon-based fuels have powered civilization since the dawn of the industrial era, delivering enormous wealth, convenience, and well-being even as they overheated the atmosphere. Luckily, the idea that reducing greenhouse-gas emissions will wreck our economy, as President Bush said in 2005 when defending his opposition to the Kyoto Protocol, is disproved by experience. "In Britain," King told the environmental Web site Grist, "our economy since 1990 has grown by about 40 percent, and our emissions have decreased by 14 percent."
Ultimately, society must shift onto a new energy foundation based on alternative fuels, not only because of global warming but also because oil "will get harder and costlier to find" in the years ahead, says Ronald Oxburgh, the former chairman of the British arm of Royal Dutch Shell oil. "The group around President Bush have been saying that, even if climate change is real, it would be terribly costly to shift away from carbon-based fuels," Oxburgh continues. "Of course it would, if you try to make the change overnight. But that's not how you do it. If governments make the decision to shift our society to a new energy foundation, and they make it clear to everyone this is what we're doing by laying out clear requirements and incentives, corporations will respond and get the job done."
The opening move in this transition is to invest massively in energy efficiency. Amory Lovins, co-founder of the Rocky Mountain Institute, a think tank that consults for corporations and governments around the world, has demonstrated that measures such as insulating buildings and driving more fuel-efficient vehicles could reduce humanity's consumption of energy and natural resources by a factor of four. And efficiency investments have a demonstrated record of creating jobs and boosting profits, suggesting that emissions can be reduced without crippling economies.
One of the first moves Angela Merkel announced as the new chancellor of Germany last fall was the extension of a Green Party initiative to upgrade energy efficiency in the nation's pre-1978 housing stock. Most of that housing is in the former East Germany, where unemployment approaches 20 percent. Replacing old furnaces and installing efficient windows and lights will produce thousands of well-paying laborers' jobs that by their nature cannot be outsourced.
Corporations, too, have discovered that energy efficiency can be profitable. Over a three-year period beginning in 1999, BP invested $20 million to reduce the emissions from its internal operations and saved $650 million—32 times the original investment.
Individuals can cash in as well. Although buying a super-efficient car or refrigerator may cost more up front, over time it saves the consumer money through lower energy bills.
Efficiency is no silver bullet, nor can it forever neutralize the effects of billions of people consuming more and more all the time. It can, however, buy humanity time to further develop and deploy alternative-energy technologies. Solar and wind power have made enormous strides in recent years, but the technology to watch is carbon sequestration, a method of capturing and then safely storing the carbon dioxide produced by the combustion of fossil fuels. In theory, sequestration would allow nations to continue burning coal—the most abundant fuel in the world, and the foundation of the Chinese and Indian economies—without worsening the climate problem. "If carbon capture is not feasible, our choices are much less good, and the cost of climate change is going to be much higher," says Jeffrey D. Sachs, the director of the Earth Institute at Columbia University and a special adviser to the United Nations.
No one pretends that phasing out carbon-based fuels will be easy. The momentum of the climate system means that "a certain amount of pain is inevitable," says Michael Oppenheimer. "But we still have a choice between pain and disaster."
Unfortunately, we are getting a late start, which is something of a puzzle. The threat of global warming has been recognized at the highest levels of government for more than 25 years. Former president Jimmy Carter highlighted it in 1980, and Al Gore championed it in Congress throughout the 1980s. Margaret Thatcher, the arch-conservative prime minister of Britain from 1979 to 1990, delivered some of the hardest-hitting speeches ever given on climate change. But progress stalled in the 1990s, even as Gore was elected vice president and the scientific case grew definitive. It turned out there were powerful pockets of resistance to tackling this problem, and they put up a hell of a fight.
Call him the $45 million man. That's how much money Dr. Frederick Seitz, a former president of the National Academy of Sciences, helped R. J. Reynolds Industries, Inc., give away to fund medical research in the 1970s and 1980s. The research avoided the central health issue facing Reynolds—"They didn't want us looking at the health effects of cigarette smoking," says Seitz, who is now 94—but it nevertheless served the tobacco industry's purposes. Throughout those years, the industry frequently ran ads in newspapers and magazines citing its multi-million-dollar research program as proof of its commitment to science—and arguing that the evidence on the health effects of smoking was mixed.
In the 1990s, Seitz began arguing that the science behind global warming was likewise inconclusive and certainly didn't warrant imposing mandatory limits on greenhouse-gas emissions. He made his case vocally, trashing the integrity of a 1995 I.P.C.C. report on the op-ed page of The Wall Street Journal, signing a letter to the Clinton administration accusing it of misrepresenting the science, and authoring a paper which said that global warming and ozone depletion were exaggerated threats devised by environmentalists and unscrupulous scientists pushing a political agenda. In that same paper, Seitz asserted that secondhand smoke posed no real health risks, an opinion he repeats in our interview. "I just can't believe it's that bad," he says.
Al Gore and others have said, but generally without offering evidence, that the people who deny the dangers of climate change are like the tobacco executives who denied the dangers of smoking. The example of Frederick Seitz, described here in full for the first time, shows that the two camps overlap in ways that are quite literal—and lucrative. Seitz earned approximately $585,000 for his consulting work for R. J. Reynolds, according to company documents unearthed by researchers for the Greenpeace Web site ExxonSecrets.org and confirmed by Seitz. Meanwhile, during the years he consulted for Reynolds, Seitz continued to draw a salary as president emeritus at Rockefeller University, an institution founded in 1901 and subsidized with profits from Standard Oil, the predecessor corporation of ExxonMobil.
Seitz was the highest-ranking scientist among a band of doubters who, beginning in the early 1990s, resolutely disputed suggestions that climate change was a real and present danger. As a former president of the National Academy of Sciences (from 1962 to 1969) and a winner of the National Medal of Science, Seitz gave such objections instant credibility. Richard Lindzen, a professor of meteorology at M.I.T., was another high-profile scientist who consistently denigrated the case for global warming. But most of the public argument was carried by lesser scientists and, above all, by lobbyists and paid spokesmen for the Global Climate Coalition. Created and funded by the energy and auto industries, the Coalition spent millions of dollars spreading the message that global warming was an uncertain threat. Journalist Ross Gelbspan exposed the corporate campaign in his 1997 book, The Heat is On, which quoted a 1991 strategy memo: the goal was to "reposition global warming as theory rather than fact."
"Not trivial" is how Seitz reckons the influence he and fellow skeptics have had, and their critics agree. The effect on media coverage was striking, according to Bill McKibben, who in 1989 published the first major popular book on global warming, The End of Nature. Introducing the 10th-anniversary edition, in 1999, McKibben noted that virtually every week over the past decade studies had appeared in scientific publications painting an ever more alarming picture of the global-warming threat. Most news reports, on the other hand, "seem to be coming from some other planet."
The deniers' arguments were frequently cited in Washington policy debates. Their most important legislative victory was the Senate's 95-to-0 vote in 1997 to oppose U.S. participation in any international agreement—i.e., the Kyoto Protocol—that imposed mandatory greenhouse-gas reductions on the U.S.
The ferocity of this resistance helps explain why the Clinton administration achieved so little on climate change, says Tim Wirth, the first under-secretary of state for global affairs, who served as President Clinton's chief climate negotiator. "The opponents were so strongly organized that the administration got spooked and backed off of things it should have done," says Wirth. "The Kyoto negotiations got watered down and watered down, and after we signed it the administration didn't try to get it ratified. They didn't even send people up to the Hill to talk to senators about ratifying it."
"I wanted to push for ratification," responds Gore. "A decision was made not to. If our congressional people had said there was even a remote chance of ratifying, I could have convinced Clinton to do it—his heart was in the right place.... But I remember a meeting in the White House with some environmental groups where I asked them for the names of 10 senators who would vote to ratify. They came up with one, Paul Wellstone. If your most optimistic supporters can't identify 10 likely gettables, then people in the administration start to ask, 'Are you a fanatic, Al? Is this a suicide mission?'" (Clinton did not respond to e-mailed questions.)
James Hansen, without singling out any individual, accuses global-warming deniers of "acting like lawyers, not scientists, because no matter what new evidence comes in, their conclusion is already decided." Richard Lindzen responds that Hansen has been wrong time and time again and operates "one of the worst climate models around." Lindzen agrees that both global temperature and atmospheric concentration of carbon dioxide have increased over the last century. But temperatures won't rise much further, he says, because humans aren't the main driving force in the climate system. The reason most scientists disagree with him, Lindzen explains, is simple careerism. "Once President Bush the elder began spending $2 billion a year on climate science, scientists developed a self-interest in maintaining this is an urgent problem," he says, adding that the scientific community's fixation on climate change will be remembered as an episode of "mass insanity."
Among many rebuttals to the deniers' arguments, perhaps the most authoritative collection is found on the Web site of Britain's national academy of science, the Royal Society. But such rebuttals have little impact on true believers, says Robert May, the Society's former president. "[Nobel Prize-winning physicist] Max Planck used to say that people don't change their minds [because of evidence]," he adds. "The science simply moves on and those people eventually die off."
But if the deniers appear to have lost the scientific argument, they prolonged the policy battle, delaying actions to reduce emissions when such cuts mattered most. "For 25 years, people have been warning that we had a window of opportunity to take action, and if we waited until the effects were obvious it would be too late to avoid major consequences," says Oppenheimer. "Had some individual countries, especially the United States, begun to act in the early to mid-1990s, we might have made it. But we didn't, and now the impacts are here."
"The goal of the disinformation campaign wasn't to win the debate," says Gelbspan. "The goal was simply to keep the debate going. When the public hears the media report that some scientists believe warming is real but others don't, its reaction is 'Come back and tell us when you're really sure.' So no political action is taken."
