Every spring and summer, the snowpack in the mountains melts slowly, delivering a flow to Californians about the time when rainfall is decreasing and demand for water is rising. The state has "built an entire water supply system around the reliable appearance of snowpack in our mountains," said Jeffrey Mount, a water scientist. That could be a problem. New research shows the already-melting snowpack across the West, and especially California, could be dramatically smaller or vanished altogether by the end of the century, the Los Angeles Times reports.
Global warming could help make winters with little or no snow common in roughly 35 years, the study found. That could have major effects not just on California’s water supply, but on soil, plants, and wildlife, as well as the frequencies of wildfires. The study was run by researchers at the Lawrence Berkeley National Laboratory and published in Nature Reviews Earth and Environment. The report provides a solid timeline for the first time, a co-author said, by synthesizing snowpack projections from "any and every available study." The researchers expressed alarm at that timeline.
"This isn't some hypothetical make-believe future," said the co-author, Erica Siirila-Woodburn. The snowpack in the Sierra Nevada and Cascade ranges is about 20% smaller than it was in 1950. The difference is roughly the capacity of Lake Mead. The snowpack usually is deepest around April 1, but this year it was at just 60% of its average, the state reported. "This is something that's already happening now," she said. There's been a periodic lack of snow before, but the researchers said California could endure five-year stretches of low to no snow before the end of the 2040s unless greenhouse gas emissions are cut, per NBC. (The drought in the Southwest is the most severe ever recorded.)