Worst Droughts in a Millennium Predicted for Western United States

Research uncovers more evidence for possibly decades-long droughts. Climate change is the likely culprit in effects that may challenge infrastructure and agricultural output throughout the century.

1 minute read

February 23, 2015, 10:00 AM PST

By Philip Rojc @PhilipRojc


Drought

Anthony Quintano / Flickr

Although California’s current four-year dry spell may not be directly related, climate scientists have discovered evidence suggesting that the western states may have to contend with decades-long droughts. These so-called "megadroughts" would have a magnitude unprecedented for at least the past thousand years.

The hypothesized cause is nothing new: "research suggests that rising temperatures connected to climate change—not necessarily a decrease in precipitation—will boost the risks of drought far beyond that caused by historic natural variability." Increased evaporation will make it difficult to retain existing reservoirs, while a hotter climate will drive greater demand for irrigation and municipal water.

Eric Holthaus reports on the scientists' methodology and potential wide-reaching effects. Long-term, these may include economic repercussions and lifestyle changes for "tens of millions of people from San Francisco to Las Vegas and from Dallas to Des Moines."

Thursday, February 12, 2015 in Slate

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