Calculation of snow avalanche runout distance.

Abstract

Evaluation of the maximum runout distance of snow avalanches is one of the most important problems in avalanche zoning. It is also one of the most difficult and controversial subjects in avalanche research. This is especially true in avalanche-prone districts where there may be a need for housing, so that calculation of maximum runout distance has many implications concerning possible future accidents and damage. Models that will predict avalanche runout distance are therefore much in need. Such models should be based on a small number of parameters. These parameters should be as objective as possible, and not be based on subjective judgment from the various avalanche experts handling the problem. The purpose of this paper is to study extreme avalanche runout distance based on (1) topographic parameters from about 200 avalanches, (2) calculation of runout distance from the same collection of avalanches based on a numerical /dynamical model, and (3) combination of the two models.