The Indian Space Research Organisation (ISRO) has released long-term satellite imagery covering the catchments of Indian Himalayan river basins from 1984 to 2023. The imagery reveals significant changes in glacial lakes, with 676 lakes larger than 10 hectares identified during 2016-17 notably expanding since 1984.
Of the expanding lakes, 130 are situated within India, with 65, seven, and 58 lakes located in the Indus, Ganga, and Brahmaputra River basins, respectively. An overwhelming majority (89%) of these lakes have expanded more than twice their original size, while 10 have grown between 1.5 to 2 times and 65 have expanded 1.5 times.
Elevation-based analysis shows that 314 lakes are located in the 4,000 to 5,000 m range and 296 lakes are above 5,000 m elevation. The glacial lakes are categorized into four types based on their formation process: moraine-dammed, ice-dammed, erosion, and other glacial lakes.
Among the 676 expanding lakes, the majority are moraine-dammed (307), followed by erosion-formed (265), other (96), and ice-dammed (8) glacial lakes. ISRO emphasizes the significance of long-term change analyses derived from satellite data for understanding glacial lake dynamics. These insights are crucial for assessing environmental impacts and developing strategies for Glacial Lake Outburst Floods (GLOF) risk management and climate change adaptation in glacial environments.
