01 October 2009

About that Southeast Drought


A new paper has been released by Richard Seager, of Columbia University, and colleagues in the Journal of Climate that discusses the significance of the recent drought in the U.S. southeast. Some science deniers (a term I just coined;-) have asserted that the drought and its impacts were caused by greenhouse gas-driven climate change. Seager et al. tell a different story, one that will be familiar to readers of this blog. The droughts impacts were in fact driven by societal change, specifically increasing demand for water. Here is what the Columbia University press release says:

A 2005-2007 dry spell in the southeastern United States destroyed billions of dollars of crops, drained municipal reservoirs and sparked legal wars among a half-dozen states—but the havoc came not from exceptional dryness but booming population and bad planning, says a new study. Researchers from Columbia University’s Lamont-Doherty Earth Observatory defied conventional wisdom about the drought by showing that it was mild compared to many others, and in fact no worse than one just a decade ago. According to the study, climate change has so far played no detectable role in the frequency or severity of droughts in the region, and its future effects there are uncertain; but droughts there are essentially unpredictable, and could strike again at any time. The study appears in the October edition of the Journal of Climate.

“The drought that caused so much trouble was pathetically normal and short, far less than what the climate system is capable of generating,” said lead author Richard Seager, a climate modeler at Lamont. “People were saying that this was a 100-year drought, but it was pretty run-of-the-mill. The problem is, in the last 10 years population has grown phenomenally, and hardly anyone, including the politicians, has been paying any attention.”

The paper can be found here in PDF.