Conceptual model for quantification of snow avalanche return periods

Abstract

This note is a contribution to the InfraRisk project (Module B) where one of the aims is to suggest an improved standard for hazard mapping. In particular, it is attempted to overcome the deficieney pointed out for *WP Bl Hazard Mapping” stating that today"s hazard maps are inappropriate to assess the risk inside the hazard zone (the maps define only the frequency of an expected event and most often only along a single line). The aim of this study is to establish a conceptual model for quantification of snow avalanche return periods at any given location along the avalanche track. The conceptual model is based on the modified a/B-model presented by Harbitz et al. (2001), which is again based on the original topographical/statistical /B-model (e.g. Bakkehøi et al. 1983; a summary description is also presented by Harbitz 1998).