HR: 0800h
AN: H21B-0514    [Abstracts]
TI: Snowcover Variability on a High-Altitude Rangeland in North Park, Colorado
AU: * Tedesche, M E
EM: mtedesch@lamar.colostate.edu
AF: Watershed Science, Warner College of Nat. Res. Colorado State University, Fort Collins, CO 80523-1472, United States
AU: Fassnacht, S R
EM: srf@warnercnr.colostate.edu
AF: Watershed Science, Warner College of Nat. Res. Colorado State University, Fort Collins, CO 80523-1472, United States
AU: Meiman, P
EM: pmeiman@warnercnr.colostate.edu
AF: Rangeland Ecosystem Science, Warner College of Nat. Res. Colorado State University, Fort Collins, CO 80523-1472, United States
AU: Fernandes-Gimenez, M E
EM: gimenez@warnercnr.colostate.edu
AF: Rangeland Ecosystem Science, Warner College of Nat. Res. Colorado State University, Fort Collins, CO 80523-1472, United States
AB: Snowpacks in high-altitude plateaus, such as North Park, Colorado, are subject to dramatic changes in depth and area on large and small scales. The shallow depths of snow cover enhance the effects of albedo-induced melt. Over a winter the snowpack can completely disappear and re-accumulate several times. Low night temperatures can aid in persisting a shallow snowpack late into the spring. Wind contributes greatly to the variability of snow cover in this environment where the terrain is relatively flat and vegetative cover is small. The variability of the ground cover density and profile height provided by shrubs creates numerous, random depressions and isolated voids that can capture blowing snow. Spatial variability in snowpack cover can be observed between areas with different densities of vegetative cover. Differences in albedo between ground cover densities become most apparent during the initial accumulation and during the snowmelt phase. These differences are also associated with variability in snow present: early in the snow season snow depths can be greater around shrubs while late in the season depths can be lesser than the surrounding open areas. Snow depths, especially early in the season, can be misleading due to void space under more dense braches that have become prone due to the overlying snow mass. To assess net accumulation and snowmelt patterns, albedo, snow depth, and snow density were measured within and between rangeland shrubs. The predominant shrub type is big mountain sage (Artemisia tridentata), but some cinquefoil (Potentilla fruticosa) are also present.
DE: 0736 Snow (1827, 1863)
DE: 0740 Snowmelt
DE: 1816 Estimation and forecasting
DE: 1863 Snow and ice (0736, 0738, 0776, 1827)
DE: 1884 Water supply
SC: Hydrology [H]
MN: 2007 Fall Meeting