Item: How to assess and communicate persistent weak layers: a forecaster’s perspective
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Title: How to assess and communicate persistent weak layers: a forecaster’s perspective
Proceedings: International Snow Science Workshop Proceedings 2018, Innsbruck, Austria
Authors:
- Patrick Nairz [ Avalanche Warning Service Tyrol, Innsbruck, Austria ]
- Lukas Ruetz [ Avalanche Warning Service Tyrol, Innsbruck, Austria ]
- Karel Kriz [ University of Vienna, Department of Geography and Regional Research, Vienna, Austria ]
Date: 2018-10-07
Abstract: Avalanche forecasters try to obtain a realistic picture of the snowpack structure and stability in order to assess danger levels efficiently. This picture can shift with time, however, and may be very complex, especially when forecasters have to deal with multiple persistent weak layers, undergoing changes in different regions, elevations and aspects. In the Tyrolean Alps, the winterseasons 2014/15 through 2016/17 were characterized by severe problems comprising such multiple persistent weak layers. The situation was often challenging not only for backcountry skiers or local authorities, but also for avalanche forecasters. As detailed analysis of these winter seasons and experiences of the most recent winter season 2017/18 shows, there was an excellent match of the predicted spatial distribution of persistent weak layers with a significant dissemination of accidents in these areas. On the other hand, the investigation helped the forecaster to focus more intensively on decisive parameters, such as the development of crusts, the elevational limits of rain events, large temperature disparities between adjacent layers or long-term observations of existing weak layers using stability testing methods (i.e. ECT). Both, the assessment of and the communication of prevailing persistent weak layers form an inseparable unit. Similar to different educational concepts where probabilistic, analytic and intuitive methods are combined, depending on education and skills, different communication tools for different user groups are pursued. These tools range from the utilization of complex diagrams for professionals to widely distributed and easy to grasp alarm-messaging services via social-media channels such as WhatsApp or Instagram.
Object ID: ISSW2018_P17.3.pdf
Language of Article: English
Presenter(s):
Keywords: avalanche forecasting, communication, persistent weak layers
Page Number(s): 1553-1558
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