Good News From a Drier Amazon
Sometimes things unfold better than we imagine. Apparently drought-stricken regions of the Amazon forest grew particularly vigorously during the 2005 drought, according to new research from the University of Arizona. A prominent global climate model predicted the Amazon forest would "brown down" after just a month of drought and eventually collapse as the drought progressed—one of John Schellnhuber's scary tipping points.
Detailed, long-term observations from two NASA satellites (one mapping the greenness of vegetation, one measuring rainfall) gave the researchers seven to nine years of observations. They compared "normal" years to the 2005 drought, and found that intact areas of Amazonia that received below-normal rainfall in 2005 had above-average greenness.
Apparently the drought did not accelerate global warming, as feared. In fact, during the 2005 drought, Amazonia's trees flourished in the sunnier-than-average weather, most likely by tapping water deep in the forest soil. By continuing to grow, they consumed more carbon dioxide, drawing down atmospheric levels, and in theory, at least, producing a negative feedback loop that might have actually slowed global warming.
Lest Limbaugh Rush bolster his feeble argument against climate change, these new data do not undermine the science of global warming. Rather they caution that we can't afford to substitute opinion for observation. Our planetary systems are hugely complex, our grasp of them fragile, even as Earth struggles to maintain equilibrium. Unlike the naysayers out there, I still see nature as our ally. JULIA WHITTY