Creation of the snow avalanche susceptibility map of the krkonoše mountains using gis

This article deals with the development of the snow avalanche susceptibility map in the Czech part of the Krkonoše Mountains using the free Geographic Information System (GIS) GRASS. The area susceptibility map consists of two components: the morphological risk map,which is derived from the digital terrain model (DTM) and describes the slope steepness,aspect and curvature of the slope,and the protecting vegetation influence map,which is based on supervised image classification (spectrozonal aerial photos) and takes into consideration the importance of vegetation cover. The final map also includes starting zones calculated on the basis of significant changes in slope steepness and approximate shapes of avalanche paths based on these zones. In the map development,the layer of measured paths of avalanche cadastre in the Czech part of the Krkonoše Mountains was used,partly to gain the morphological characteristics of starting zones and partly to check the quality of the map.