Climate Change Code Red

 

By SYD BAUMEL

 

NASA's top climatologist and five of his colleagues think the UN Intergovernmental Panel on Climate Change (IPCC) is way off in its increasingly pessimistic warnings about global warming. They're not pessimistic enough. In a scientific paper that ups the rhetoric of climate change warnings to code red, James Hansen, the Director of NASA's Goddard Institute for Space Studies – yes, the director who blew the whistle when Bush tried to muzzle him – and five other scientists forecast that global warming has put the planet on the brink of a rapid meltdown of the polar ice sheets in Greenland and West Antarctica. The flooding will be “cataclysmic” if we don't take drastic action now. If you've seen Al Gore's PowerPoint show you'll know what Hansen and his associates at the Goddard Institute, the University of California and Columbia University are talking about. It's called the “albedo flip.” Light-coloured (high albedo) objects – read: ice and show – reflect most of the sunlight that hits them. They're hard to heat up. But when they start to melt, crack, slip and sink, the relatively dark water (lower albedo) that takes their place absorbs much more heat from the sun. Suddenly the pace of ice sheet melting picks up and begins to accelerate so rapidly that a tipping point – an albedo “flip” - occurs and before you know it the world's polar ice sheets are like ice cubes vanishing from a shot glass on a hot summer's day. When the polar ice caps have gone – potentially before the end of this century, Hansen and associates predict – sea levels will have risen over 200 metres, not many centimetres as the IPCC forecasts. But that's not all. Trapped under the planet's frozen ocean floors and tundras are deposits of frozen methane (methyl hydrate). As the earth continues to heat up, these massive global warming time bombs are due to start melting. Ounce for ounce, methane has __-times the global warming power of CO2. The last time such a chain reaction occurred 55 million years ago, fun-in-the-sun lovers enjoyed a 68 degree C temperature surge - and mass extinctions, Hansen et al. caution. In fact, the history of the planet is studded with hot and cold climate change cataclysms, according to the geologic record. Like the people-powered one we're cruising to be bruised by if we don't take massive preventative action (and possibly even if we do), they have never been politely slow and steady, Hansen et al. write. Because of the chain reaction nature of global warming, they've always followed a vicious cycle, “positive feedback” pattern: a very slow burn (as we enjoyed until the 1990s), then a stampede – a “runaway greenhouse effect,” as Hansen et al. put it. “The Earth, and the creatures struggling to exist on the planet, have been repeatedly whipsawed between climate states,” Hansen and his associates write. “But civilization developed, and constructed extensive infrastructure, during a period of unusual climate stability, the Holocene, now almost 12,000 years in duration. That period is about to end.” The respected environmental writer George Monbiot has been studying and warning about global warming for years. This July he wrote that when he read the paper by Hansen et al., “I found, to my amazement, that my hands were shaking. This has never happened to me before, but nor have I ever read anything like it.” Sitting on a train at the time, Monbiot writes that he “looked up from the paper, almost expecting to see crowds stampeding through the streets. I saw people chatting outside a riverside pub. The other passengers on the train snoozed over their newspapers or played on their mobile phones. Unaware of the causes of our good fortune, blissfully detached from their likely termination, we drift into catastrophe.” Neither Hansen nor Monbiot believe we're doomed. We just have to stop drifting.