Mapping of avalanche start zones susceptibility: Arazas basin, Ordesa and Monte Perdido National Park (Spanish Pyrenees)

摘要

In this work, we present avalanche start zone susceptibility (scale 1:25,000) in the Arazas basin, located in the Aragonese central Pyrenees and integrated into the Ordesa and Monte Perdido National Park. The basic variables considered include: (i) altitude of the regional annual isotherm of 0°C; (ii) slope; (iii) ground cover; and (iv) morphology of the slope (curvature). The information used to analyze these variables came from several sources, which were managed using a geographic information system: (i) digital altimetry (scale 1:5000); (ii) aerial flights photography; and (iii) regional climatological data. To perform the mapping of avalanche start zones susceptibility, a multicriteria analysis was applied. The information showed in the final map was structured in four main sections: (1) avalanche start zone susceptibility (classified as low, moderate, high and very high); (2) hydrological elements; (3) topographic elements; and (4) anthropic elements. This cartography could be a useful instrument in the management and planning of the study area, frequently visited because of its status as a National Park.