Snowfall in San Gabriels Could Drop 30 to 40 Percent, UCLA Study Says

Snowfall in the San Gabriel Mountains could drop 30 to 40 percent by mid-century, according to a new UCLA study.  

The UCLA study, conducted by UCLA climate expert Alex Hall, was released on Friday by the school.  Hall's previous research has indicated that Southern California could warm 4 to 5 degrees by midcentury.

This study predicts the 30 to 40 percent snowfall reduction by midcentury if depending whether climate mitigation is undertaken or not. 

With climate mitigation that number could hold steady through the year 2100, but with none, the mountains could see a two-thirds reduction by 2100 compared to the snowfall levels around the year 2000.

Water resources and the local environment are among the key potential impacts raised by the UCLA study's authors, according to press release issued by the school:

Besides losing the beautiful snow-lined mountain drop, it's possible that the loss of snowfall could affect flood control in the foothill areas and make new challenges for local water collection.

"Less snow could also mean changes in the seasonal timing of local water resources, greater difficulty controlling floods, and damage to mountain and river ecosystems," according to the UCLA study release.San Marino draws most of its water from the local Raymond and San Gabriel basins, according to a report from California American Water, the city's water provider.
However, having more precipitation drop as rain instead of snow might not make more of a challenge for keeping local ground basins full of water, according to one former local utility manager interviewed by the Los Angeles Times.
The greater issue might be that having more rain and less snow could make flood control more difficult.
"Increased flooding is possible from the more frequent rains, and springtime runoff from melting snowpack will happen sooner," wrote Hall in the study.
The UCLA graphic above illustrates the potential drop in snow fall levels in the San Gabriels and other Southern California ranges based on if nothing is done and if there is mitigation.

For more on the study, visit the UCLA website.

Editor's note: This story has been changed to reflect that 30 to 40 percent figure is dependent on whether or not climate mitigation action is taken or not.