The disastrous hurricanes of recent years have become the poster children of global warming.
But Roger A. Pielke Jr., an environmental policy expert at the University of Colorado at Boulder, wondered whether the billions of dollars of damage was caused by more intense storms or more coastal development.
After analyzing decades of hurricane data, Pielke concluded that rising levels of carbon dioxide had little to do with hurricane damage. Rather, it boiled down to a simple equation: Build more, lose more.
“Everything has been put on the back of carbon dioxide, and carbon dioxide cannot carry that weight,” he said.
Pielke’s analysis, published last month in the journal Natural Hazards Review, is part of a controversial movement that argues global warming over the rest of this century will play a much smaller role in unleashing planetary havoc than most scientists think.
His research has led him to believe that it is cheaper and more effective to adapt to global warming than to fight it.
Instead of spending trillions of dollars to stabilize carbon dioxide levels across the planet -- an enormously complex and expensive proposition -- the world could work on reducing hunger, storm damage and disease now, thereby neutralizing some of the most feared future problems of global warming.
Hans von Storch, director of the Institute of Coastal Research in Germany, said that the world’s problems were already so big that the added burdens caused by rising temperatures would be relatively small. It would be like going 160 kilometers per hour on the autobahn when “going 150 . . . is already dangerous,” he said.
Consider a United Nations estimate that global warming would increase the number of people at risk of hunger from 777 million in 2020 to 885 million by 2080, a 14% rise, if current development patterns continue.
That increase could be counteracted by spending on better irrigation systems, drought-resistant crops and more-efficient food transport systems, said Mike Hulme, founding director of the Tyndall Centre for Climate Change Research at the University of East Anglia in England.
“If you’re really concerned about drought, those are much more effective strategies than trying to bring down greenhouse gas concentrations,” he said.
Downplaying the importance of emissions reductions has raised hackles among scientists around the world, who say that the planet-wide effects of global warming will eventually go beyond humans’ ability to deal with it.
“You can’t adapt to melting the Greenland ice sheet,” said Stephen H. Schneider, a climatologist at Stanford University. “You can’t adapt to species that have gone extinct.”
Other scientists say that time is running out to control carbon dioxide emissions and that the call to adapt is providing a potentially dangerous excuse to delay. If adaptation were so simple, they say, it would have already been done. But the developing world remains wrought with hunger and disease and vulnerable to natural disasters.
Pielke acknowledges that there are enormous political hurdles to overcome with his strategy, and he recognizes that his views have made him and like-minded researchers the new pariahs of global warming.
“I’ve been accused of taking money from Exxon or being a right-wing hack,” he said.
But unlike those who argue that humans are not warming the globe, the new skeptics accept the scientific consensus on the causes and effects of climate change. Their differences are over what to do about it.
“The radical middle -- that’s how we talk about ourselves,” said Daniel Sarewitz, a public policy expert at Arizona State University who has collaborated with Pielke on climate policy studies.
Pielke, whose career has focused on the politics of science, likes to describe the scattered collection of scientists and policy wonks as the “non-skeptic heretic club.”
The science of global warming was laid out in a series of reports last year by the U.N. Intergovernmental Panel on Climate Change, which shared the Nobel Peace Prize with former Vice President Al Gore. The reports said that temperatures were likely to climb 3 to 8 degrees Fahrenheit by century’s end if emissions continued to grow.
They detailed a likely future of worsening famine in Africa, expanding floods as sea levels rise as much as 23 inches, and accelerated species extinction. To avoid the worst, the reports warned that emissions must be reduced 50% to 80% by mid-century, keeping temperature rise below 2 degrees.
The cost, according to the U.N. panel, would amount to as much as 3% of world gross domestic product over the next 20 years, or more than $20 trillion.
The heretics support emissions cuts too, but warn that they have been oversold as a solution to coming catastrophe.
Exhibit A is hurricanes.
The spate of recent storms, particularly Hurricane Katrina in 2005, has come to be seen as a harbinger of a warmer world -- a view popularized by Gore’s 2006 documentary, “An Inconvenient Truth.”
Pielke’s new analysis considered 207 hurricanes that hit the United States between 1900 and 2005. He looked at their strength and course and then overlaid them on a modern map that included all development over the years.
He found that the most devastating storm, had it occurred today, would be the Great Miami Hurricane of 1926, popularly known as the Big Blow. Its path through the now heavily developed southern tip of Florida would have caused $157 billion in damage, followed by Katrina, whose toll was $81 billion. Six of the top 10 most damaging storms occurred before 1945.
Pielke and his colleagues determined that with each decade, the damage potential for any given storm doubled, on average, because of development.
Malaria, another problem that may worsen with global warming, also has solutions.
Higher temperatures could allow malaria-carrying mosquitoes to move into Africa’s highland regions, where people have little natural immunity from the parasite. Still, the extra burden would be a fraction of the millions of cases that afflict the continent each year.
“If you look at Africa, only 2% is above 2,000 meters,” said Paul Reiter, an expert on mosquito-borne disease at the Pasteur Institute in Paris. He said that far more deaths would come from the malaria parasite’s growing resistance to drug treatments.
“We should be more concerned with controlling the disease than trying to change the weather,” said Reiter, who recommended heavier use of pesticides to kill mosquitoes -- the same strategy that eradicated malaria in the United States and elsewhere.
The World Health Organization estimates that over the next decade annual malaria deaths could be cut from 1 million to 250,000 for $3.2 billion a year.
But critics say a major flaw in the adaptation strategy is that the effects of global warming will be unpredictable. It may be possible to adapt to some easily identifiable effects, but when the ecology of an entire planet is altered by rising levels of carbon dioxide, nobody understands the full range of potential perils.
Dealing with the effects without cutting emissions is “like mopping up the floor while keeping one of the faucets still running,” said Dr. Jonathan Patz, an environmental health scientist at the University of Wisconsin at Madison and a member of the U.N. climate panel.
Other scientists say that some changes could be so catastrophic -- such as sudden changes in the ocean currents that control regional climates -- that it would be impossible to adapt to them.
The only way to prevent the unexpected is cutting emissions, said U.N. climate panel member Gary Yohe, an economist at Wesleyan University.
Although most scientists agree that adaptation should play a major role in absorbing the effects of climate change, they say that buying into the heretics’ arguments will dig the world into a deeper hole by putting off greenhouse gas reductions until it is too late.
The heretics believe that time works to their benefit, arguing that technological advances over the next 50 years will ultimately make reducing carbon dioxide in the atmosphere affordable.
Pielke says that even if his critics are right, it is becoming clear that the world lacks the political will to enact global emissions cuts.
China’s growing emissions are on pace to double those of the United States in a decade, and the country shows little interest in slowing down. The United States has refused to cap its emissions, and much of Europe is failing to satisfy even the modest terms of the Kyoto Protocol, the 1997 landmark treaty on greenhouse gases.
“I would characterize us as realists,” Pielke said. “Realists on what is politically possible.”