Snow avalanches - rough susceptibility zones
Susceptibility areas for snow avalanches is a national series of maps showing areas that are potentially vulnerable to snow avalanches (susceptibility areas) at a general level. The maps show potential source areas and run-out areas for snow avalanches. Your attention is drawn to the fact that the areas covered by source areas are in practice run-out areas as well, as avalanches that are triggered right at the top of the source area move through the source areas below, before reaching the run-out areas at the bottom. Therefore, both source areas and run-out areas should generally be used together when using the dataset for analysis purposes. The susceptibility areas are identified by means of a data model which uses the slope of the terrain to recognise terrain where avalanches may be triggered. The run-out area is calculated automatically from each trigger area. No fieldwork is done when defining the areas, so the impacts of local factors (e.g. forest, terrain details, safety measures implemented, etc.) have not been assessed. The susceptibility areas are not applicable to the risks linked with slush avalanches.
Submitter: Norwegian Mapping Authority
Owner: Norwegian Water Resources and Energy Directorate
Version number 1