IN 2002, THE PENTAGON began exploring the national security implications of global warming. Military brass commissioned a report, subtitled ”Imagining the Unthinkable,” that forecast the impacts of an abrupt change in the Earth’s climate. It’s a grim scenario: Prolonged droughts in northern Europe and the United States lead to acute food and water shortages, while typhoons and hurricanes devastate low-lying regions like Bangladesh. Africa is crippled by disease and famine; southern Europe is flooded with millions of refugees; in the Persian Gulf, Chinese and U.S. naval forces square off over access to Saudi oil fields. ”Every time there is a choice between starving and raiding,” the authors of the study point out, ”humans raid.”
When the report was made public last year, it was widely criticized as unnecessarily alarmist. Global warming couldn’t inspire that much chaos, could it? But after witnessing the devastation wrought by Hurricane Katrina – the bloated bodies, the toxic sludge, the rapes and looting, the bureaucratic failures, the political cowardice and finger-pointing – the Pentagon scenario seems less farfetched. Katrina showed us the colossal force of a pissed-off climate, reminding us of how powerless we are in the face of it. The storm was a natural disaster, to be sure – but it was also a vision of our possible future.
For years, climate skeptics and fossil-fuel hacks argued that global warming was a fantasy of tree-huggers and blue-state hypocrites. But scientific evidence that the planet is indeed heating up has become so overwhelming that even noted skeptics like Ronald Bailey, editor of Global Warming and Other Eco-Myths, have converted. After reviewing the latest satellite temperature data confirming a warming trend, Bailey wrote, ”Anyone still holding onto the idea that there is no global warming ought to hang it up.”
Instead of denying the issue, some skeptics have switched tactics: They now argue that life on a hotter planet will be no big deal. ”It’s not the warming itself that we should be concerned about,” Fred Singer, the dean of global-warming skeptics, argued at a power-industry conference last year. ”It is the impact. And what is the impact on agriculture? I’d say it’s positive. What’s the impact on forests of greater levels of CO2 and higher temperatures? It helps them grow, so it’s good. What is the impact on sea level? Nothing. It will not raise sea levels. What is the impact on recreation? It’s good and bad. You get, on the one hand, maybe a little less winter sports; on the other hand, you get more sunshine and maybe better beach weather.” Rather than cutting carbon-dioxide emissions, statisticians like Bjørn Lomborg argue, it would be cheaper to simply adapt to climate changes as they come. To hear the skeptics tell it, preparing for the consequences of global warming is no more difficult than nailing an extra sheet of plywood on the roof.
Hurricane Katrina should put an end to this happy delusion. The failure to prepare adequately for a hurricane slamming into New Orleans, the most predictable of natural disasters, demonstrates just how vulnerable we are to the kind of climate chaos imagined in the Pentagon report. As for adaptation being cheaper than cutting CO2 emissions, that is a tricky argument to make when the cost to clean up and rebuild after Katrina alone could run as high as $200 billion – by far the most expensive disaster in U.S. history. A full-fledged energy revolution, on the other hand, could be a source of jobs and inspiration that would make the Silicon Valley boom look like a bake sale.
I’m not suggesting that solar panels would have saved New Orleans or that Katrina was caused by global warming in any direct sense – devastating hurricanes are nothing new on the Gulf Coast. Overbuilding in hurricane-prone areas, as well as the destruction of protective wetlands, are the biggest reasons for the increasing destructiveness of hurricanes. But greater sea surface temperatures in the Gulf can also contribute to their intensity: Hurricanes are essentially heat engines, powered by the difference in temperature between the top of the sea and the air above the storm. ”I think it’s a safe bet that the next hundred years are going to have more Category 4 and 5 hurricane strikes than the last hundred years,” says Kerry Emanuel, a hurricane expert at the Massachusetts Institute of Technology. ”But we’re not used to thinking on those time scales, and that’s part of the problem.”
The larger problem with seeing global warming as a harbinger of better beach weather is that it assumes that the climate is a steady, balanced system. And it has been – recently. For most of history, however, the climate has been wildly unstable. During the Younger Dryas, a climatic event that ended about 11,500 years ago, Greenland’s temperature warmed fifteen degrees Fahrenheit in less than ten years. That’s like going to sleep one night in Alaska and waking up in Costa Rica. Many researchers believe that greenhouse gases may be one factor pushing the system out of balance. ”You might think of the climate as a drunk,” writes Richard Alley, a paleoclimatologist at Pennsylvania State University. ”When left alone, it sits; when forced to move, it staggers.” Every ton of carbon dioxide we dump into the atmosphere is another kick in the drunk’s ass.
New Orleans will rise again. The toxic mud will be washed away, the levee will be rebuilt, the evacuation plans will be revamped. But if that’s all that happens – if Katrina is seen as simply a random act of God, or Mother Nature, and does not wake us up to the dangers we face in an overheated climate – then we are in deep trouble. The real message of Katrina is not that big winds blow down houses. It’s that on the Greenhouse Planet, we all live in New Orleans.