Researchers at Oregon State University have developed a new way to measure the water content of snow.
David Hill is a professor at OSU in its Water Resources program. He said snowpack was traditionally measured at its usual peak, on April 1. Instead, “We chose an approach that is a little bit more holistic, and kind of adds up the snowpack over the year." He told KLCC their new method "tells you both how long and how much at the same time. And to us that seemed like a better approach, in terms of gaining an understanding of the role that snow is playing in a given season.”
Hill said snow normally holds water like a reservoir, and moderates stream flow. With Oregon’s dry summers, that’s helped provide water when it’s needed.
But, Hill said, their data found snowfall has changed, especially in the past 10 years, with more intense storms, and several snowpack peaks per season. He said going forward, water managers will need to work with new water storage options and timing.
Hill said the study also considered snow density, because lighter, fluffy snow holds less water than dense, heavy snow.
The research, recently published in Hydrology and Earth System Sciences, found, over a 20-year period, a 22% decrease in the amount of water held in snowpack over a season in the mountains of the lower 48 states. Data from several dozen sites in Oregon from 1980 to 2020 found a 48% decline in snow / water storage per year.
