Temperature, Not Precipitation, Has Greater Impact On Northwest Snowpack

Feb 27, 2017

Scientists have new cautionary predictions based on the low Northwest snowpack levels of the last two winters.

In 2014 and 2015, Oregon’s western Cascades had a low snowpack. Overall, it wasn’t because of low precipitation. It was because temperatures were higher.

Eric Sproles, a hydrologist at Oregon State University, said the 2014 snowpack was low and 2015 was even lower.

“We didn’t have snow. A lot of the reservoirs almost went empty, we had algae blooms, the lower elevation ski areas didn’t open,” Spoles said. “The bad news is that that will happen about once a decade, we’re going to have a snow pack like that.”

Sproles said results from his study, published in the Journal Cryosphere, show the Northwest snowpack is extremely sensitive to temperatures that warm even by two degrees Celsius.

But he said it’s not all “doom and gloom,” because the study offers land managers a way to predict and plan for drier conditions.

According to scientists, the situation is similar in California's northern Sierras as well as the mountains of Chile.

"We use snowpack as a reservoir [for water],” Sproles said. ”Mountain snowpack holds about four to five times as much water as the actual [man-made] reservoirs, at least in the McKenzie [River basin.]”