Once-in-a-Millennium Megadrought—Happening Now in the Western United States

The Western United States is experiencing a drought the scale of which has only been seen once before in the past 1,200 years, according to a new study. Climate change is not a future problem, say the researchers responsible for the study, it's here.

1 minute read

April 20, 2020, 8:00 AM PDT

By James Brasuell @CasualBrasuell


Dry Lake in Arizona

trekadnshoot / Shutterstock

"A vast region of the western United States, extending from California, Arizona and New Mexico north to Oregon and Idaho, is in the grips of the first climate change-induced megadrought observed in the past 1,200 years," report Andrew Freedman and Darryl Fears.

That claim originates by a study published on April 16 in the journal Science, "[comparing] modern soil moisture data with historical records gleaned from tree rings, and [finding] that when compared with all droughts seen since the year 800 across western North America, the 19-year drought that began in 2000 and continued through 2018 (this drought is still ongoing, though the study’s data is analyzed through 2018), was worse than almost all other megadroughts in this region." Only one megadrought in the 1500s was more intense, according to the study.

As noted in the article, the study also connects the current megadrought to climate change by comparing soil moisture with and without global warming-induced trends. The researchers "were able to determine that 30 to 50 percent of the current drought is attributable to climate change."

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