The scientific debate about whether there is a global warming problem is pretty much over. A leading international group of climate scientists reported last month that the evidence for global warming is "unequivocal" and that the likelihood it is caused by humans is more than 90 percent. Skeptical researchers will continue to question the data, but this isn't a "call both sides for comment" issue anymore. For mainstream science, it's settled.
The question now is what to do about global warming. This is a political problem more than a scientific one. The solutions (if we can agree on any) will require political will and imagination -- and also pain. That was my only reservation about the Oscar night celebration of Al Gore's leadership on this issue. The gowns and black ties and the celebrity back-slapping made it look like dealing with global warming will be fun, a walk down the red carpet. But it's more likely to be about catastrophe and how to share the pain.
These issues come into focus in a startling new report by futurist Peter Schwartz. He turns the usual discussions upside down: Rather than starting with detailed estimates of climate change (how much temperatures will increase; how much sea levels will rise; what new diseases will be spawned), he looks instead at systems that already are vulnerable to such stresses.
What Schwartz discovers with his stress-testing makes climate change even scarier: The world already is precarious; the networks that maintain political and social order already are fragile, especially in urban areas; the dividing line between civilized life and anarchy is frighteningly easy to breach, as the daily news from Iraq reminds us. We look at the behaviors of butterflies and migratory birds as harbingers of climate change. But what about early effects on human beings? "The steady escalation of climate pressure will stretch the resiliency of natural and human systems," writes Schwartz. "In short, climate change pushes systems everywhere toward their tipping point."
Schwartz's report, "Impacts of Climate Change," was prepared by his consulting group, Global Business Network, for a U.S. government intelligence agency he doesn't identify. The text of the report is available at the online discussion forum PostGlobal (http://www.washingtonpost.com/postglobal). Here's a brief trek through the ravaged landscape Schwartz describes.
A first set of disasters waiting to happen involves stressed ecosystems. Human actions -- deforestation, overfarming, rapid urbanization -- have created special vulnerabilities to catastrophic natural events that are likely as the climate changes globally. In an interview, Schwartz cited the example of Haiti, which because of deforestation and loss of topsoil is "an ecosystem at the edge." A prolonged drought or a devastating hurricane could tip Haiti over that threshold -- and produce a refugee crisis of tens of thousands of boat people fleeing a devastated country.
Or take the problem of rising sea levels: Climate scientists are uncertain how fast the icecaps will melt and the seas will rise. But in Bangladesh, where millions of people live at or near sea level, even a small increase could produce a catastrophe. In a severe monsoon, 60 million to 100 million people could be forced to flee inundated areas, Schwartz warns, producing "the single greatest humanitarian crisis we have ever seen."
Lack of water may be as big a problem as flooding. Schwartz notes that more than 700 million people now live in arid or semi-arid areas. Climate change could tip this balance, too, producing severe water shortages and even "water wars." Tens of millions of people may become water migrants. The world's feeble political systems can't cope with existing migration patterns, let alone this human tide.
And finally, there is the problem of maintaining social order in a stressed world. You don't have to go to Baghdad to see how quickly the social fabric can be shredded; just look at New Orleans after Hurricane Katrina. The stresses come in part from rapid urbanization. Schwartz notes that in 1900, one in 20 people lived in cities; today it's about half, and the percentage is rising fast. Without strong and supple governments, this could become a world of vigilantes and militias, desperate to control scarce resources.
The big problems in life aren't the ones that hit you by surprise but the ones you can see coming. That's surely the case with climate change: We can measure it, we can imagine its catastrophic effects. But can we do anything to stop it? If we let ourselves visualize how bad it could get, as Schwartz does in this report, will we make changes that might reduce the disaster? That's the real stress test: It's coming at us. What are we doing about it?
David Ignatius