The Spatial and Temporal Distribution of Melt Rates Across the Southern Rocky Mountains, USA

Abstract:

About 20% of the world’s population relies on melting snow for their main water supply. Many of these areas are mountainous and there is limited in situ monitoring of snow accumulation and melt due to few stations and the lack of representativeness of these stations in this complex terrain. Most of the existing stations only collect precipitation and temperature data, thus modeling of snowmelt often uses temperature as an index for the full energy balance needed to physically model melt. Across the Western United States (U.S.), there are currently about 700 snow telemetry (SNOTEL) stations that monitor precipitation and temperature, as well as snow water equivalent (SWE) and snow depth. Across the Southern Rocky Mountains in the central-western U.S., 90 SNOTEL stations have been operating since the late 1970s or mid-1980s. These stations were used to estimate the daily snowmelt rate as a function of the daily average air temperature, in millimeters of snow melt per day per degrees Celsius, over half-month periods to consider the seasonality of incoming solar radiation. The spatio-temporal variability of melt was then evaluated based on the location, topography, and canopy characteristics for each station. It is expected that this melt rate spatio-temporal variability can applied to other continental regions across the globe.