Southwest and Central Plains face unprecedented drought

Climate Change -  Climate change is creating an “unprecedented” risk of severe drought in the Southwest and Central Plains. Rising temperatures and decreasing rainfall mean that future drought could be more extreme than any drought seen in at least the past 1,000 years and the effects could reverberate for urban dwellers and farmers across the regions.

The 1930s Dust Bowl created post-apocalyptic conditions for the Central Plains, but Lisa Graumlich, who heads the University of Washington’s College of the Environment, said that the severe drought that plagued the Southwest from 1100-1300, ”makes the Dust Bowl look like a picnic.” That drought occurred during what researchers have called the Medieval Climate Anomaly and contributed to widespread ecosystem shifts and the collapse of civilizations across the Southwest.

Yet both those droughts pale in comparison to the severity of drought projected to befall those regions — which encompass all or part of 17 states from California to Louisiana to Minnesota — during the latter half of the 21st century if greenhouse gas emissions continue to rise according to a new study published in Science Advances. Both regions are all but guaranteed to experience a severe drought that would last at least a decade, with the odds of a drought lasting multiple decades at about 80 percent. In comparison, the chances of a multi-decadal drought occurring during 1950-2000 was less than 10 percent.

Previous studies have looked forward at drought risks and also drawn comparisons to the Dust Bowl but none have drawn comparisons with tree ring records of the past. This one not only does that but uses a suite of 17 climate models and three drought measures to provide as much insight as possible.