Snowfall Measurements at Wind-exposed and Sheltered Sites in the Rocky Mountains of Southeastern Wyoming

Abstract

Snowfall is an important driver of physical and biological processes in alpine systems. Previous work has shown that surface deposition of snow can vary for reasons not directly related to precipitation processes and that this variance has consequence for water budgets in snow-dominated terrestrial systems. In this work, measurements were made over several winter seasons in a forest-meadow ecotone in the Rocky Mountains of Southeastern Wyoming. Two groups of measurements - both with wind-exposed and sheltered precipitation gauges - were analyzed. Reasonable agreement between snow deposition from a hotplate gauge (exposed) and snow deposition from a SNOTEL pillow gauge (sheltered) is reported. The other result is that snow deposition is enhanced at an exposed gauge that was deployed on the leeward side of a forest-meadow edge. The enhancement is approximately a factor of two and varies with wind direction and speed and with upwind forest coverage. The enhancement is greater than documented in an earlier investigation of Rocky Mountain snow deposition; however, in that study measurements were conducted above tree line.