Megadrought Predicted For US West

First it was the Koch brothers' skeptic joining in the warnings about climate change.

Now three scientists have data predicting what they call megadrought in the US for years to come, writing in the Sunday New York Times:

BY many measurements, this summer’s drought is one for the record books. But so was last year’s drought in the South Central states. And it has been only a decade since an extreme five-year drought hit the American West. Widespread annual droughts, once a rare calamity, have become more frequent and are set to become the “new normal...”

Future precipitation trends, based on climate model projections for the coming fifth assessment from the Intergovernmental Panel on Climate Change, indicate that droughts of this length and severity will be commonplace through the end of the century unless human-induced carbon emissions are significantly reduced. Indeed, assuming business as usual, each of the next 80 years in the American West is expected to see less rainfall than the average of the five years of the drought that hit the region from 2000 to 2004...

These climate-model projections suggest that what we consider today to be an episode of severe drought might even be classified as a period of abnormal wetness by the end of the century and that a coming megadrought — a prolonged, multidecade period of significantly below-average precipitation — is possible and likely in the American West...

Many Western cities will have to fundamentally change how they acquire and use water... Some regions will become impossible to farm because of lack of irrigation water.