Item: Monitoring Glide Avalanches Using Time-Lapse Photography
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Title: Monitoring Glide Avalanches Using Time-Lapse Photography
Proceedings: Proceedings, 2012 International Snow Science Workshop, Anchorage, Alaska
Authors:
- Alec van Herwijnen [ WSL, Swiss Federal Institute for Snow and Avalanche Research SLF Davos, Switzerland ]
- Ron Simenhois [ Coeur Alaska, Juneau, Alaska, USA ]
Date: 2012
Abstract: Glide avalanches can present a significant hazard to people and property in snowy climates. These often destructive avalanches are difficult to forecast and hard to control. Glide avalanches occur when the entire snowpack glides over the ground until an avalanche releases. The slow gliding process can take place over a few hours and up to several months. Since the gliding interface is at the base of the snow cover, direct correlations with meteorological conditions have thus far not been identified. Hence, traditional forecasting methods relying on snowpack and weather observations are relatively inaccurate. Past research has shown that glide rates generally increase before a glide avalanche releases. Thus, monitoring changes in glide rates is essential for glide avalanche forecasting. Currently, available glide monitoring techniques are costly, somewhat unreliable and difficult to deploy over large areas. In this paper, we report on a cheap and simple glide monitoring method using time-lapse photography. This method was first tested between 2008 and 2010 in the Eastern Swiss Alps around Davos, Switzerland. Two time-lapse cameras monitored areas with known glide avalanche activity. To track changes in glide rates, the number of dark pixels in an area around a glide crack is counted in each image. An increase in glide rates was observed several hours prior to avalanche release. These encouraging results led to the development of a prototype real-time monitoring system in Southeastern Alaska, USA, which has been in use since 2010. Our results show that time-lapse photography can be used to monitor snow glide rates simultaneously in several start zones and potentially provide insight into when, or if, a glide avalanche will release.
Object ID: issw-2012-899-903.pdf
Language of Article: English
Presenter(s): unknown
Keywords: glide avalaches, time-lapse photography, start zones, switzerland
Page Number(s): 899-903
Subjects: glide avalanches time lapse photography avalanche forecasting
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