Determination of potential avalanche hazard in Karaj watershed using geographic information system

Iran country due to high climate diversity had been always exposed to natural disasters. One of the disasters is avalanche in snowy areas that can impose considerable damages on Iran social and economic position. This issue especially on the Chaloos road as one of the traffic routes in Iran is a serious threat and every year, it brings irreparable damages to life and property. Therefore, considering the importance of site selection and zoning of avalanche hazard areas is necessary and essential. In this study, avalanche hazard areas were determined using geographic information system (GIS) and remote sensing techniques. For this purpose, convexity, concavity, altitude and slope maps were produced using topographic map within the Arc GIS 10.2. Land use and land cover of the study area was then derived using satellite images. In the next step, the aftermentioned produced layers in GIS software was weighted and surveyed and then the high risk areas to avalanche was determined. The results obtained this study showed that null, moderate, high and very high avalanche risk areas cover 22.16, 25.69, 27.78 and 24.36 percent, respectively. These areas have significant compliance with ground realities.