The effects of climate change on seasonal mountain snowpacks could have “potentially catastrophic” consequences for water management in the western United States, according to a study released Oct. 26 from the Lawrence Berkeley National Laboratory.
The review paper led by Berkeley Lab researchers Erica Siirila-Woodburn and Alan Rhoades synthesizes the science behind the future of the snowpack in the western United States. It also serves as a “call to action” about the “dire implications” for water management practices.
“Snow is this critical resource, and we know it’s going away — but the details of how it’s going away really matter when we manage water,” said co-author Andrew Jones, a scientist at the Berkeley Lab’s Climate and Ecosystem Sciences Division.
The paper finds if greenhouse gas emissions continue unabated along a high-emissions scenario, “low-to-no snow” winters will become a regular occurrence in the western United States in the next 35 to 60 years.
Coastal mountain ranges in the western United States such as the Sierra Nevada in California will likely experience some of the most dramatic snow loss, Rhoades said.
“The snowpack is unique because it acts as a giant water tower that stores for late spring and summer,” said Andrew Schwartz, station manager and lead scientist at UC Berkeley’s Central Sierra Snow Lab. “Low snow or no snow is going to make managing our water a lot harder.”
The paper warns that water conveyance and storage infrastructure was built and is managed under certain assumptions about spring snowmelt, which are increasingly out of date.
Changes in snowmelt quantities and timing will change how much water is available and how much can be stored, said co-author Naomi Tague, professor of ecohydrology at UC Santa Barbara, in an email.
“We’ve built our water regulations, water policy and water infrastructure on patterns of water availability — both its timing and magnitude, from historic patterns — that are now decades old — and those patterns have changed,” Tague said in an email.
The authors predict the future will require a diverse portfolio of strategies to adapt to a “low-to-no snow” future.
Adaptation strategies suggested in the paper include forecast-informed reservoir operations, managed aquifer recharge and vegetation management, among others.
“We don’t want to fall into this trap of despondence,” said co-author Benjamin Hatchett, assistant research professor at the Desert Research Institute in Reno, Nevada. “We still have a ton of opportunities both to slow the roll of longer-term climate change and perhaps more importantly to improve the resilience of our communities and societies to extremes.”
