Publication Date October 25, 2021 | Climate Nexus Hot News

Atmospheric River Dumps Precipitation On California, Risking Landslides In Wildfire Burn Scars

United States
Rocks and vegetation tumbled down the mountainside in the Sierra Nevada.
Rocks and vegetation tumbled down the mountainside and across Highway 70 in Plumas County, Calif., near the Dixie fire zone in the Sierra Nevada. Credit: Noah Berger, Associated Press

A Category 5 "bomb cyclone" dumped historic amounts of precipitation across much of North California Sunday, creating dangerous flooding and landslide conditions in the region scarred by recent wildfires. The "atmospheric river" dumped more than 5.35 inches of rain on Sacramento on Sunday, the most in a 24 hour period since record keeping began during the Rutherford B. Hayes administration (1877). Other locations at higher elevations were expected to see even more precipitation, and as much as 2 feet of snow were expected in the Sierra Nevada. Flooding was reported across the Bay Area. Climate change, caused by the extraction and combustion of fossil fuels, not only worsens extreme precipitation events by increasing the amount of moisture the atmosphere can hold, it also worsens the risks of landslides in areas incinerated by climate-supercharged wildfires. State police closed a stretch of State Route 70 in two counties after multiple landslides in the Dixie Fire burn scar, and the NWS issued flash flood warnings for both Dixie and Caldor Fire burn scars. Numerous locations across the state were under evacuation orders because of the potential for mudslides in fire scars. “If you are in the vicinity of a recent burn scar and haven’t already, prepare now for likely debris flows,” the Sacramento weather service tweeted. “If you are told to evacuate by local officials, or you feel threatened, do not hesitate to do so. If it is too late to evacuate, get to higher ground.” The historic rainfall will not undo the massive drought, made more severe by climate change, the state faces. “Even with 5 inches of rain in Sacramento, our deficits are immense,” Jeffrey Mount, a geologist and water expert at the Public Policy Institute of California told the Sacramento Bee. “We’re basically missing two years of ‘precip’ in this basin. It’s not a drought buster.” (Precip so far: Sacramento Bee $, APSacramento Bee $, CBSNBCWashington Post (video)San Francisco Chronicle $; Landslides: San Francisco Chronicle $; Atmospheric River: AxiosWashington Post $, New York Times $, The HillAP; Drought: Sacramento Bee $; Climate Signals background: Extreme precipitation increase2021 Western wildfire seasonDrought)