Concerns that California might remain in a “snow drought” this winter have eased after a series of storms this month blanketed the Sierra Nevada with a near-average amount of snow for this time of year.
Lake Mead is America’s largest reservoir, supplying water for 25 million people across the southwest. It’s also drying up — a kind of poster child for the ongoing drought in the West. But upstream, a much larger but lesser known source of stored water is also disappearing: mountain snow.
This is how climate change is throwing one of the United States’ most critical sources of water out of whack.
The current multi-year drought across the West is the most extensive and intense drought in the 22-year history of the U.S. Drought Monitor. Precipitation deficits during the first three months of 2022, across parts of the western U.S., are at or near record levels. As the climatological wet season ends across portions of the West, with below average snow cover and reservoirs at or near record-low levels, concerns for expanding and intensifying drought and water resource deficits are mounting.
During March, the average contiguous U.S. temperature was 44.1°F, 2.6°F above the 20th-century average. This ranked in the warmest third of the 128-year period of record. The year-to-date (January-March) average contiguous U.S. temperature was 36.3°F, 1.2°F above average, ranking in the middle third of the record.
The March precipitation total for the contiguous U.S. was 2.26 inches, 0.25 inch below average, and ranked in the driest third of the 128-year period of record. The year-to-date precipitation total was 5.66 inches, 1.30 inches below average, ranking seventh driest in the January-March record.
Temperatures were above average across much of the West and along the East Coast. California ranked sixth warmest for the January-March period.
February total precipitation was record low at over 200 Snow Telemetry sites, leading to continued expansion of snow drought conditions across the West. Fifty percent of the SNOTEL sites now have snow water equivalent that is less than one-third of historical conditions, up from 22% in early February. In California, the driest January and February in state history has led to a March 1 statewide snowpack of less than 70% of average, down from 160% at the start of the new year.
The western United States has built their water infrastructure on a melting foundation, and unless we do something about global warming, scientists worry the consequences will be catastrophic.
On April 1 each year, researchers ski and snowshoe out into the high mountains of the western United States to jab stakes into the bright, crystalline snow, checking the thickness of the blanket. But in 2012, many researchers could barely travel on snow to their test sites—and when they got there, there was almost no snow to measure.
2013 was almost as bad. 2014, the same. And in 2015, on the April 1 assessment, many sites across the Sierra Nevada mountains were bald and snowless—the worst snow drought, scientists found, in at least the last 500 years.
The Water News Network is San Diego County’s source for water news and information.
