Characterizing the nature and variability of avalanche hazard in western Canada

Abstract

Correspondence to: Bret Shandro (bshandro@sfu.ca) AbstractThe snow and avalanche climate types maritime, continental and transitional are well established and have been used extensively to characterize the general nature of avalanche hazard at a location, study interseasonal and large-scale spatial variabilities and provide context for the design of avalanche safety operations. While researchers and practitioners have an 10 experience-based understanding of the avalanche hazard associated with the three climate types, no studies have described the hazard character of an avalanche climate in detail. Since the 2009/10 winter, the consistent use of Statham et al.'s (2017) conceptual model of avalanche hazard in public avalanche bulletins in Canada created a new quantitative record of avalanche hazard that offers novel opportunities for addressing this knowledge gap. We identified typical daily avalanche hazard situations using Self Organizing Maps (SOM) and then calculated seasonal prevalence values of these situations. This approach 15 produces a concise characterization measure that is conducive to statistical analyses, but still provides a comprehensive picture that is informative for avalanche risk management due to its link to avalanche problem types. Hazard situation prevalence values for individual seasons, elevations bands and forecast regions provide unprecedented insight into the interseasonal and spatial variability of avalanche hazard in western Canada.

Tree‐Ring Derived Avalanche Frequency and Climate Associations in a High‐Latitude, Maritime Climate

“…Our study area is comprised of six individual avalanche paths in the Coast Mountains of southeastern Alaska near Juneau, which is the most populous city in the region (Figure 1). We sampled pairs of avalanche paths in three distinct subregions within the same general maritime climate type (Shandro & Haegeli, 2018), providing climatological coherence across the study region (Lader et al, 2020). Mean monthly temperatures range from −2 to 14°C and mean annual precipitation is 1,400 mm in Juneau.…”