Scott A. Kampas
EF4
- Joined
- Dec 10, 2003
- Messages
- 303
ANTHROPOGENIC CLIMATE CHANGE:
New Models Indicate Dramatic Global Cooling Imminent
Richard A. Kerr
New Models Indicate Dramatic Global Cooling Imminent
Richard A. Kerr
The first results from the new GCM at NASA’s GISS lab are revamping the way we understand climate change. The new twist is shocking. Contrary to all earlier work, a dramatic, 5 degrees C cooling in the Northern Hemisphere is expected within 10 years. That shakes up what had seemed to be a consensus, although some balk at this new perspective.
Mark Cane, of the GISS lab, and 15 colleagues report the stunning findings. In similar studies by other GCM’s, anthropogenic greenhouse gasses in the atmosphere were predicted to result in global warming. In the Cane study, published this week in Nature, the modelers varied eight parameters –two more than any previous work- so that they could explore nonlinear interactions between parameters. The perturbed parameters did in fact interact nonlinearly to heighten climate sensitivity, in a stunning fashion. None of the simulations showed Northern Hemisphere warming for the next 50 years. And most simulations did not fall far from the model's sensitivity of 1.4ºC when run with no parameters perturbed. But the inevitable long tail of results on the high-sensitivity side ran out to 10 degrees C of cooling, an effect opposite any kind of study before it.
How likely is a dramatic cooling? "We can't yet give a probability for our results," says Cane. "Our results are very sensitive to our prior assumptions," such as which parameters are perturbed and by how much. Previous studies suffer from the same limitations, he says. “And frankly, we don’t want to believe these results.â€
Other climate researchers will take some convincing. "I just can't believe the climate will cool," says paleoclimatologist Thomas Crowley of Duke University in Durham, North Carolina. Climate's responses to past, natural changes in greenhouse gases or equivalent climate drivers, such as volcanic eruptions, have all reflected warming, he says. Until modelers can confirm the new results—as other researchers update their models to try to replicate the GISS work--Crowley will stick with a moderately strong warming.[/b]