Evaluating The Effects Of Precipitation And Wind Speed On Snow Water Equivalence Along An Elevation Gradient Using 30 Years Of LTER Snow-Pit Data
Brandes, Henry 1 ; Houston, Nathaniel 2 ; Carter, Roger 3 ; Cushing, Melissa 4; Schuster, Jessica 5
1 University of Colorado at Boulder
Long term trends of precipitation and wind speed were evaluated along elevation gradients to assess the dominant effects on snow water equivalence (SWE) using current and historical records of Long-Term Ecological (LTER) research data collected at Niwot Ridge (NWT), 35 km west of Boulder, Colorado. Data was collected weekly during winter snow cover at NWT-LTER snow-pit sites: C-1 (3021 m), Soddie (3345 m), and the alpine station—Saddle (3528 m). Student interns from the University of Colorado at Boulder dig snow-pits to measure and record snow depth and density. Snow-pit data was coupled with 30-year historical LTER climate data to evaluate principle effects of wind speed and precipitation on SWE along an elevational gradient. Historical climate records from NWT LTER (1980-present) indicate general warming trends across all elevations. Average April 1 SWE for the years 1981-2013 was 11.7 inches at the NWT SnoTel site in the subalpine at 3021 m a.s.l, and we aim to assess SWE measurements for March, April, and May 1st across the elevation gradients of sub-alpine to alpine environments. NWT has one of the longest historical records of manual snow-pit data, providing an excellent source for evaluating trends in snow water equivalence and snowmelt in the Rocky Mountains, essential for water management in Colorado.