The Current Megadrought In The American West

The last time the American West was so dry, they were starting to build Pueblos at Mesa Verde and Charlemagne was the Emperor of the Carolingian Empire.

The extreme heat and dry conditions of the past few years pushed what was already an epic, decades-long drought in the American West into a historic disaster that bears the unmistakable fingerprints of climate change. The long-running drought, which has persisted since 2000, can now be considered the driest 22-year period of the past 1,200 years, according to a study published Monday in the journal Nature Climate Change.

Previous work by some of the same authors of the new study had identified the period of 2000 through 2018 as the second-worst megadrought since the year 800 — exceeded only by an especially severe and prolonged drought in the 1500s. But with the past three scorching years added to the picture, the Southwest’s megadrought stands out in the record as the “worst” or driest in more than a millennium. . . .

The authors attribute 19 percent of the severe 2021 drought, and 42 percent of the extended drought since the 21st century began, to human-caused climate change.

From the Washington Post (February 14, 2022).

A 2010 paper in PNAS explores much of the same data.