Los Angeles area mountains are on track to lose up to 40 percent of its snowfall in nearly four decades, according to a UCLA study released today. If greenhouse gas emissions continues unabated, snowfall will be two-thirds less by the year 2100.
"Climate change has become inevitable, and we're going to lose a substantial amount of snow by midcentury,'' stated Alex Hall, a professor at UCLA who led the study. "But our choices matter. By the end of the century, there will be stark differences in how much snowfall remains, depending on whether we begin to mitigate greenhouse gas emissions." The study surveyed the San Gabriel, San Bernardino, San Jacinto, San Emigdio, and Tehachapi mountains.
Less snowfall could damage mountain and river ecosystems and equate to sizeable economic losses for snow-dependent businesses like ski resorts in Wrightwood and Big Bear. If immediate efforts are made to substantively reduce emissions through mitigation, mid-century loss of snow will be limited to 31 percent. If not, the mountains will lose 66 percent of their current snowfall by the end of the century.
Streamflow from mountain snow is one of the critical water resources for California but Los Angeles County isn't likely to be critically impacted. "L.A. is not dependent on snowpack in the San Gabriel Mountains for our water supply," said Jonathan Parfrey, the executive director of Climate Resolve, a nonprofit that assists on climate strategies and communications, including for today's report.
Los Angeles County gets bulk of its water supply from outside sources but global warming will undoubtedly have larger-scale implications and affect places where we do get our water, like the Sierra Nevada mountains and the Colorado river. Less snow could also mean changes in the seasonal timing of local water resources and greater difficulty controlling floods. Another challenge would be finding a way to store water as opposed to snow.
Los Angeles is already on the right track to curbing emissions, Parfrey noted. Under Assembly Bill 32, California is aiming for 80 percent reduction of greenhouse gases below 1990 levels by 2050. "In Los Angeles, we are 28 percent below 1990 today," he said. "As a city we could very likely hit that target 80 percent by 2050."
The city of Los Angeles invested in the UCLA study and has created a framework to assist with mitigation efforts. "This science is clear and compelling: Los Angeles must begin today to prepare for climate change," Los Angeles Mayor Antonio Villaraigosa stated. Citywide efforts include improving bicycle infrastructure, electric car ownership incentives, and energy efficiency rebates. "The city is getting off coal, using more renewable power, and really investing in non-fossil fuel for transportation," Parfrey added.
Today's study is the second of five from UCLA on climate issues about the greater Los Angeles area. The first study, released last summer, focused on hotter temperatures in the region.