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Megadrought plaguing Southwest is worst the region has seen in 1,200 years

Researchers with Nature Climate Change analyzed tree ring patterns, which delineate soil moisture levels over periods of time, to conclude that the current megadrought is worse than one that hit the region in the late 1500s and is the most severe since one in 800 AD.

The study, which analyzed a region stretching from southern Montana to northern Mexico and from the Pacific Ocean to the Rocky Mountains, found that human-caused global heating accounts for more than 40% of the severity of the dry spell.

"The turn-of-the-21st-century drought would not be on a megadrought trajectory without anthropogenic climate change," reads the study, led by Park Williams, an associate professor at the University of California in Los Angeles.

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