Item: Avalanche danger ratings and deaths, putting things into perspective
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Title: Avalanche danger ratings and deaths, putting things into perspective
Proceedings: International Snow Science Workshop Proceedings 2018, Innsbruck, Austria
Authors:
- Terry Eyland [ Bishop’s University, QC, Canada ]
Date: 2018-10-07
Abstract: Avalanche forecasters spend a lot of time to determine current and predicted avalanche danger levels, but to what extend does this danger rating have an influence on whether people head into the backcountry or not? Some avalanche professionals say that considerable is the most deadly avalanche danger. In absolute terms it may be true that considerable claims the most deaths, but in relative terms (exposure time) the story may be quite different. For this study, Glacier National Park (Rogers Pass) in British Columbia was the main source of data. The data shows that 80-90% of the days happen at a moderate or considerable danger rating. We highlight that based on 2016-17 skier days, for each death at high, we would have needed 28 deaths at considerable, 46 deaths at moderate and 25 deaths at low to keep relative avalanche danger the same. Moreover, regression results show that skiers are significantly more likely to go skiing when the avalanche danger is moderate or considerable compared to high, which should be obvious. However, the key result is that the coefficient, which represents the increase in skiers, is roughly the same for both danger levels. It is as if moderate or considerable have the same influence on whether someone decides to head out or not. We recommend the removal of the extreme danger rating (which rarely gets used) to separate moderate in the lower half and considerable in the upper half of the scale.
Object ID: ISSW2018_O17.4.pdf
Language of Article: English
Presenter(s):
Keywords: Decision-making, Avalanche Danger Scale, Human Factors, Avalanche Education
Page Number(s): 1501-1505
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