Avalanche risk management in backcountry skiing operations

Harpa Grímsdóttir
2004
Over the last 34 years Canada has had an average of 11 avalanche fatalities per year and during the past five years this average has increased to 16 fatalities per year. Today, avalanche accidents happen primarily to people during recreational pursuits, and about half of the victims over the last 20 years were backcountry skiers. Backcountry skiing operations in Canada are making a constant effort to improve their avalanche safety. This study is based on data from a large heli-skiing operator
more » ... i-skiing operator in Canada; Canadian Mountain Holidays (CMH). The first objective of this study was risk analysis based on data from CMH's database, Snowbase. Skier triggered avalanches were analysed in term of factors such as elevation level, aspect, stability rating and the time of the year. When looking at human triggered avalanches, it is not possible to analyse the risk associated with these factors based on avalanche data alone; it is essential to have an idea about where and when people are skiing. Fortunately, Snowbase also contains information about the usage of defined ski runs within the operation areas, and therefore it is possible, perhaps for the first time, to extract some ideas about the relative risk associated with the different factors. The study shows that the historical risk of accidentally triggering an avalanche greater than size 1 depends highly on the stability rating, with the highest risk under "poor" stability. The risk is greater in higher elevation levels than lower down, and it is lower during late season than earlier on. The risk does not depend as much on aspect as may be indicated from avalanche data alone. However, it is relatively high in the N-NE-E sector. These factors are not independent of each other so analyses of combined factors were also performed. The second objective was to extract knowledge on avalanche risk management from professional mountain guides. Questionnaire and interviews with professional mountain guides were used as the tools for that, as well as observation of guiding in act [...]
doi:10.14288/1.0099777 fatcat:gctvxjn7cbbn5iysf3pqfnx7jq