Modeling Avalanche Susceptible Zones across the Indo-China Border around the Galwan Valley, Ladakh (India)

Abstract

Snow avalanche is considered the most destructive disaster among natural disasters in high mountain areas and results in severe injuries, deaths, impacts on public infrastructure, residential areas, communication systems, and so on. It is very difficult to obtain in situ observation of avalanche activities in the inaccessible terrain at high altitudes known for their harsh climate. The present study demonstrated avalanche susceptibility modeling in the Indo-China border area extending between the Galwan Valley and Pangong-Tso Lake using the Geographic Information System and the multicriteria decision-based Analytical Hierarchy Process model. Geoinformatics-based terrain mapping revealed that moderate (21°-35°) north- and northeast-facing slopes with convex surfaces within the relief range of 5000-5500 m were more susceptible to avalanche events. Avalanche susceptibility zonation demonstrated 11.97%, 23.8%, 24.06%, 25.3%, and 14.87% of the study area falling under very high, high, moderate, low, and very low avalanche susceptible zones. The accuracy of the present study is depicted by 73.4% area under curve value and higher frequency ratio value of 0.01437 in very high susceptible zones, proving AHP as a good spatial model to carry out avalanche forecasting studies in data-scarce regions.