Pacific Standard: When it comes to water shortage, it seems the worst is yet to come. A new climate analysis indicates that by the end of the century, the United States Southwest and Central Plains regions are likely to experience drought conditions worse than any in the last millennium. These impending conditions could pose “a major adaptation challenge” for humans in a rapidly changing climate.

“We’re talking about megadrought risk,” says co-author of the study and Columbia University professor Toby Ault — an 80 percent chance or more of decades-long droughts before the end of the century.

Though it’s well established that droughts and other extreme climate events are likely to become more intense over the next century, Ault, along with climatologists Benjamin Cook and Jason Smerdon note that the Americas are no stranger to massive droughts, like the Medieval “megadrought” between roughly 1,100 and 1,300 C.E. and the Little Ice Age that followed several centuries later. This raises a vital question: Compared to those events, how bad will the coming droughts be? [Continue reading…]