Mapping of glacial lakes and glacial lake outburst flood in Kinnaur district, Himachal Pradesh using remote sensing and GIS

Abstract Glacial lake outburst floods (GLOFs) are a severe and escalating threat to livelihoods and infrastructure in high-mountain areas around the world. To implement a first-order assessment of GLOF risk across the Kinnaur district of Himachal Pradesh (HP), we combine modelling approaches that capture both current and future potential for GLOF triggering, quantification of affected downstream areas, and assessment of the underlying societal vulnerability to such climate-related disasters. As a result, the assessment takes into account both current glacial lakes and future lakes predicted to occur as glaciers retreat. Current hazard, vulnerability, and exposure indices are combined to indicate various risk 'hotspots,' demonstrating that high GLOF risk might occur well downstream from the glaciated headwaters where threats arise in some cases. Landsat images for the years 1989, 1998, 2008 and 2018 were used to map glacier lakes. Cartosat DEM (30 m) was used for computing topographic information including maximum, minimum, mean elevation, slope, and aspect. ArcGIS 10.8 was used to generate other characteristics such as area, slope, aspect, and drainage network. The maximum likelihood classification (MLC) algorithm was used to create the land use and land cover (LULC) maps using the supervised classification technique. To augment the findings, the study also uses the indices i.e. NDSI, NDWI, NDPI. based on the data a total of 39 glacial lakes were identified of which 10 lakes were found dangerous lakes having area > 0.1 Km2 Trans-national GLOFs originating in China's upper Satluj River Basin, in particular, pose a threat to eastern HP's downstream territories. In the future deglaciated scenario, most administrative units are expected to have a large increase in GLOF danger levels as lakes grow closer to steep headwalls, where impacts from falling ice and rock could trigger outburst occurrences. Strengthening resilience and capacities to lower the current GLOF risk will be a critical first step toward adjusting to future problems in such situations.