A n Inconvenient Truth, the hugely influential documentary starring Al Gore, is a shoo-in for an Oscar. Its riveting depictions of violent storms, collapsing ice mountains and parched deserts have scared millions of people into believing that the world faces a catastrophic fate unless we make dramatic changes to our way of life, starting now.
Climate change has made its way onto the agenda of every developed nation, even the United States, where some of the nation's biggest businesses, including energy companies, are pressing the government to take action. It even figured in George W. Bush's State of the Union speech this week.
And next week the International Panel on Climate Change (IPCC) will unleash another storm of headlines when it releases its latest consensus of scientific findings, stressing even more emphatically that human activity is causing global temperatures to rise.
Is the sky really falling? How fast and how hard? And if the vast majority of scientists agree, then why don't governments act? After all, nobody wants the world to melt.
If you're an average, concerned citizen, no one will blame you for being confused or angry. The global-warming debate has become so shrill, so political and so polarized that it's impossible for even a reasonably well-informed person to figure out who or what to believe. Only one thing is for sure: Science isn't all that is driving this debate. Politics, ideology and scaremongering are too.
Because I'm skeptical by nature, I've always discounted the environmental catastrophists. Their message is religious, not rational. But I've also spoken to enough brainy scientists to conclude that human activity is affecting the climate and that global warming is for real.
That's the famous consensus you keep hearing about. But that's where the consensus ends. Beyond that, the science is very far from settled. Scientists themselves are deeply split about how alarmed we should be, the nature of the threats we face, how imminent those threats are and what to do about them.
For apocalyptic predictions, you need only look to the bestseller list. Tim Flannery ( The Weather Makers) and George Monbiot ( Heat) both warn that civilization will collapse if we do nothing. So does Canada's David Suzuki. In Britain, James Lovelock argues that the Earth has already caught a “morbid fever,” and that “we are in a fool's climate and before this century is over billions of us will die.”
But many scientists are alarmed at the alarmism, and warn that catastrophic scenarios like the ones in Al Gore's film have pushed the science way too far. Kevin Vranes, a climate scientist who specializes in ocean/climate physics and water-resources management, has said, “Some of us are wondering if we have created a monster.”
Last fall, Professor Mike Hulme, the founding director of the Tyndall Centre for Climate Change Research in Britain, wrote a damning condemnation of climate alarmism: “Over the past few years, a new environmental phenomenon has been constructed in this country — the phenomenon of ‘catastrophic' climate change,” he wrote. “The increasing use of this term and its bedfellow qualifiers ‘chaotic,' ‘irreversible' and ‘rapid' has altered the public discourse, [which] is now characterized by phrases such as ‘irreversible tipping in the Earth's climate' and ‘we are at the point of no return.' ”
Prof. Hulme is no climate skeptic. He was the co-ordinating lead author of the chapter on “climate-change scenarios” for the last IPCC report in 2001.
To try to get a grip, I checked in with eight leading climate scientists, climate economists and climate-policy analysts. All believe that man-made climate change is a serious issue that demands action. And all reject the extremists at both ends. They represent the broad middle ground — the people whose voices have been all but drowned out by the shouting.
The first thing they stress is that while climate change is certain, what will actually happen is not. For example, scientists are pretty sure that sea levels will rise, and rising seas will pose a threat to coastal areas. But how much will they rise, and how fast, and where will they rise most? Sorry. Science can't tell you that.