Abstract

Not all avalanches are the same. Different combinations of snowpack structures and meteorological conditions create different types of avalanche problems with distinct risk scenarios. In North America, the Conceptual Model of Avalanche Hazard (CMAH) identifies nine distinct types of avalanche problems (also referred to as ‘avalanche characters’) Examples include ‘persistent slab avalanche problems’ or ‘wind slab avalanche problems’. Having a detailed understanding of the prevalence and character of the avalanche problem types in different regions and during different winters can provide valuable information on the nature and variability of avalanche hazard conditions in western Canada. Since the CMAH was introduced into the production of public avalanche bulletins in Canada in 2010, the public bulletin datasets from Avalanche Canada and Parks Canada from 2010-2016 offers a unique opportunity for examining the character of avalanche hazard in western Canada more comprehensively. In this paper, we present a first quantitative analysis of this dataset with a focus on the prevalence and nature of the nine different avalanche problem types. Our results mainly confirm our experiential understanding of the role of the nine avalanche problem types in the different mountain ranges, different seasons, and their differences in nature. However, our analysis provides an important new perspective into the snow and avalanche climates of western Canada and builds the foundation for improving our understanding the components of the CMAH and the development of future decision aids for avalanche forecasters.