Repost from by Alexandra Witze

Decades-long droughts are likely to ravage the US Southwest and Great Plains within the next century, a study suggests. This drying could be worse than any other in the past 1,000 years, including a ‘megadrought’ seven centuries ago that helped drive an ancient civilization to collapse.

The work, published on 12 February in Science Advances1, is among the first to rigorously compare the climate record of the deep past with long-term projections of today’s warming climate.

“These future droughts are not only going to be bad compared to what we’ve experienced over the historical period, but also really bad compared to the past millennium,” says Benjamin Cook, a drought researcher at NASA’s Goddard Institute for Space Studies in New York City, who led the work. “It’s going to be a pretty much fundamental shift.”