Review and future challenges in snow avalanche risk analysis

摘要: Background Snow avalanches pose a major threat to alpine communities because they affect safety in villages and on traffic routes. Therefore, dealing with avalanche danger has long tradition Alpine countries. In most countries, contribute only small degree the overall risk of country. For Switzerland, for example, represents 2% all risks (BABS, 2003). formation, geomorphology land use planning are type fast-moving mass movement. They can also contain rocks, soil, vegetation or ice. Avalanche size is classified according its destructive power (McClung Schaerer, 2006). A medium-sized slab may involve 10,000 m 3 snow, equivalent about 2,000 tons (snow density 200 kg/m ). speeds vary between 50 km/h large dry snow avalanches, whereas wet slides denser slower (20–100 km/h). If path steep, generate powder cloud. There different types (Table 5.1), particular two release: loose avalanches. Loose start from point, relatively cohesionless surface layer either snow. Initial failure analogous rotational slip sands but occurs within volume ( ) comparison much larger initiation volumes soil slides.