The Washington Post reports:

A new study provides a glimpse into the future of Western U.S. snow and the picture is far from rosy: In about 35 to 60 years, mountainous states are projected to be nearly snowless for years at a time if greenhouse gas emissions continue unchecked and climate change does not slow.

Due to rising temperatures, the region has already lost 20 percent of its snowpack since the 1950s. That’s enough water to fill Lake Mead, the nation’s largest human-made reservoir. It stands to lose another half, and possibly more, later this century, from the Rockies to the Sierra Nevada and into the Cascades of the Pacific Northwest, according to a literature synthesis conducted in the study leveraging dozens of peer-reviewed climate model projections.

The current snow situation in the West offers a preview of what the future may hold. Snow water equivalent, or the liquid water from snowpack, is much lower than normal in much of the Western United States. Snow cover across the nation is only at 6 percent — the lowest since records began in 2003.

Decades ahead, the “potential for persistent low-to-no snow to disrupt the [Western U.S.] water system is substantial, potentially even catastrophic,” the study’s authors write. [Continue reading…]