A research paper by Chris Tennant ’07 on the measurement of snowpack, the amount of snow and ice on the ground in high western mountain ranges, received an Editor’s Choice Award from the journal Water Resources Research. Only about 1 percent of articles published annually in the journal receive that recognition.

Tennant’s paper examines the use of data collected by Light Detection and Ranging imaging, known as LIDAR, to better measure snowpacks. In the western U.S., most water used for everything from municipal water supplies to irrigation and industrial uses comes from the mountain snowpacks. Accurate snowpack measurements are important for managers and others who need to forecast the amount of water available. Tennant works as a water control data systems administrator for the U.S. Army Corps of Engineering in Sacramento, California. 

He is completing post-doctoral research at the University of California, Berkeley. 

“The ability to be able to account for how much snow covers the ground over large areas has radically changed with the use of LIDAR,” Tennant said. “We’ve gone from measuring snow depth in watersheds at points that are 3-feet-by-3-feet to measuring at the scale of whole watersheds, 50-100 square miles.”

The data Tennant analyzed was collected by planes flying over watersheds using LIDAR, which measures snow depth with pulsed laser light. Prior to the use of LIDAR, scientists estimated the snowpack by inserting pipes in the ground that measured snow depth at various sites, and then made assessments of the total snow pack based on those individual sites.

“Chris’s project evaluates at a foot-by-foot scale how thick the snowpack is over a large area well beyond what humans could go out and physically measure,” said Ben Crosby, who was Tennant’s advisor at ISU. “So, now we have a continuous measure of how thick the snow cover is over a given landscape.”