Inventory and GLOF susceptibility of glacial lakes in Chenab basin, Western Himalaya

Abstract

Global warming causes glacial mass loss, leading to the growth of high-mountain glacial lakes. The presence of glacial lakes poses a significant threat to downstream communities, as they can produce destructive Glacial Lake Outburst Floods (GLOFs). Timely basin-scale inventory and GLOF susceptibility assessments are crucial, considering past GLOF events in the Himalayan region. Here, an updated inventory of glacial lakes in the Chenab basin, Western Himalayas was generated based on Sentinel-2 datasets for 2022. We assessed temporal changes and GLOF susceptibility for glacial lakes (>0.05 km2) through a multi-criteria based Analytical Hierarchical Process, classifying them into low, medium, high, and very high susceptibility classes. The results reveal 419 lakes (>0.001 km2; 9.97 ± 0.67 km2) in the basin in 2022. Glacial lakes (>0.05 km2) area increased by ∼75%, from 3.92 ± 0.58 to 6.86 ± 0.25 km2 during 1990–2022. Of the 42 lakes (>0.05 km2) evaluated, four showed very high GLOF susceptibility. The study emphasizes the impact of local geomorphology and glacier-lake interaction under warming climate, likely to increase the GLOF susceptibility in the region. Regular monitoring and detailed fieldwork for these susceptible lakes are crucial for early warning and disaster risk reduction for downstream communities.