Avalanche Warning Switzerland 2000

Abstract

Avalanche Warning has been a key task of the Swiss Federal Institute for Snow and Avalanche Research in Davos (SLF) since it was established over half a century ago. In the past, the predominant methods used for avalanche forecasting at SLF have been conventional, i.e., snow stability and avalanche hazards were predicted without analytical techniques such as formal numerical and symbolic algorithms. A paradigm shift is currently taking place. Information systems and computer programmes are becoming more and more important, assisting the forecaster in collecting and analysing large amounts of field data. Furthermore, computer models are available which simulate processes in the snow cover and calculate local and regional avalanche hazards, thereby supporting forecasters and decision makers. However, the forecaster with his intuition, experience and local knowledge still plays a decisive role in the forecasting process. While the computer helps to assimilate information, to assess the hazard risks, to support the forecaster in his decision and to distribute forecasts via modern communication channels, it is still the forecasters ultimate responsibility to check and modify the computer's prediction. This new way of avalanche forecasting, which we call 'computer-aided avalanche forecasting', is currently being implemented in Switzerland.