HR: 0800h
AN: C21B-0456    [Abstracts]
TI: Physiographic Variables to Describe Basin Scale Snow Water Equivalent
AU: * Fassnacht, S R
EM: srf@cnr.colostate.edu
AF: Watershed Science Colorado State University, 400 West University Avenue, Fort Collins, CO 80523-1472, United States
AU: Hultstrand, D
EM: dmhultst@cnr.colostate.edu
AF: Watershed Science Colorado State University, 400 West University Avenue, Fort Collins, CO 80523-1472, United States
AU: Bales, R
EM: rbales@ucmerced.edu
AF: University of California, Merced, PO Box 2039, Merced, CA 95344, United States
AB: The Natural Resources Conservation Service has installed automated Snow Telemetry (SNOTEL) stations to replace snow course measurements. These data have been used to explore the relationship between snow water equivalent (SWE) and a variety of physiographic variables for the Colorado River Basin, USA. These variables include location, slope and aspect at different scales, derived parameters to indicate the distance to sources of moisture and proximity to and characteristics of obstacles between these source areas of snow accumulation, and forest density. A weekly time step of SNOTEL SWE data from 1990 through 1999 was used to determine the most relevant variables. The most important variable was elevation. Slope at a medium scale and at a regional scale were postively correlated with SWE. The seasonal variability illustrated the necessity to formulate the regressions for each time step. The interannual variation in the relationship between SWE and physiographic variables partially corresponded with snow accumulation and the El Niño Southern Oscillation cycle, yet the variability across the basin in accumulation trends reduced this correlation. Using the suite of relevant variables, the strength of the relationship to SNOTEL data was examined for a period prior to (pre-1990) and after (post-1999) the initial study period.
DE: 0736 Snow (1827, 1863)
DE: 0740 Snowmelt
DE: 0772 Distribution
SC: Cryosphere [C]
MN: 2007 Fall Meeting