I heard the term “megadrought” used to describe the western drought. What is a megadrought?
Wester Megland, Chicago
The West and Southwest United States is experiencing an intense drought of historic proportions. The drought has persisted for 20 years in some areas and shows no signs of abating. The West and Southwest may be in the grip of a megadrought, a severe drought that lasts for decades rather than shorter droughts lasting a few years. In a study released last year, scientists identified four megadroughts that occurred during the past 1,200 years in the West and Southwest, and the fifth might now be in progress. Lake Mead, Arizona, the reservoir behind Hoover Dam, has dropped to 35 percent of capacity, its lowest level since the dam was completed in the 1930s.