Item: Applications of snotel data in formulating the south-central montana avalanche advisory
Title: Applications of snotel data in formulating the south-central montana avalanche advisory
Proceedings: 1990 International Snow Science Workshop, Bigfork, Montana USA, October 9-13
Authors: Richard Fike, Vic Pedersen, Gerald Beard and Phil Farnes
Abstract: Since the winter of 1987-1988, the South-Central Montana Avalanche Advisory Group (SCMAA) has issued advisories weekly during the avalanche season. The area covered includes the Gallatin National Forest and the northern part of Yellowstone National Park. The advisory is developed utilizing input from both public and private sectors. It includes weather forecasts, recent snow accumulation from remotely telemetered meteorological sites, avalanche occurrences from both natural and controlled sources, snowpit analyses and backcountry user observations. The Soil Conservation Service (SCS) operates a remote snow telemetry system (SNOTEL) reporting daily readings of snow water content, rainfall and temperature. A few SNOTEL sites also report wind parameters. Utilizing the USFS Avalanche Handbook technique for indexing recent snow accumulation as a measure of snow loading, a snow loading index (SLI) is computed from increments measured at SNOTEL sites. The SLI is computed on the day of the advisory for every SNOTEL site within the area of coverage and upwind in the storm track. Analyses indicate that a relationship between SLI and frequency of slides exists for controlled slides at Bridger Bowl and Big Sky Ski Areas. However, least squares regression analyses fail to demonstrate a significant correlation. Regression analyses of snow pillow and snow board data do show a strong correlation supporting the use of SNOTEL butyl pillow data as an accurate and operational real time measure of snowpack accumulation. This demonstrates the necessity of utilizing all available sources of information and resources to provide an advisory for backcountry users that is as accurate and credible as possible.
Keywords: snotel data, avalanche advisory, scmaa, forecasts, scs, sli
Digital Abstract Not Available