Early Warning Systems Related to Mountain Hazards

Abstract

Mountain hazards, such as snow avalanches, rockfall, landslides, debris flows and torrential processes are responsible for disasters and catastrophes in mountainous areas every year. In many densely populated mountain regions, governmental agencies or the inhabitants themselves try to protect settlements and traffic routes by active measures (for example check-dams, etc.) and/or passive measures (for example hazard zoning, planning of evacuation, closing of railways and roads in case of acute danger). All these measures, especially those last mentioned require early warning. We should differentiate between early warning and observation measures, concerning either (1) the basic disposition of an area for dangerous processes (e.g. long-term preconditions, such as the general instability of a slope), or (2) the variable disposition (e.g. short-term state of the snow cover on an avalanche slope), or (3) the immediate effect of triggering events (i.e. thunderstorms triggering flash floods). There is a wide range of technical realisations of early warning systems for this. In many cases the most adequate solution is a traditional warning by watchful attendants; in other cases sophisticated electronic devices provide better safety.