Satellite images of catchments of Indian Himalayan river basins show major changes in glacial lakes
The Indian Space Research Organisation’s (ISRO) longterm satellite imagery covering the catchments of Indian Himalayan river basins from 1984 to 2023 have shown signi¦cant changes in glacial lakes.
According to the ISRO, of the 2,431 lakes larger than 10 hectares identi¦ed during 2016-17, 676 glacial lakes have notably expanded since 1984.
“Speci¦cally, 130 of these lakes are situated within India, with 65, seven, and 58 lakes located in the Indus, Ganga, and Brahmaputra River basins, respectively. Of these lakes 601 lakes (89%) have expanded more than twice, 10 lakes have grown between 1.5 to 2 times and 65 lakes 1.5 times,” the ISRO said. The ISRO said that the elevation-based analysis reveals 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 categorised based on their formation process into four broad categories, namely Moraine-dammed (water dammed by moraine), Ice-dammed (water dammed by ice), Erosion (water dammed in depressions formed by erosion), and other glacial lakes.
“Among the 676 expanding lakes, the majority of them are Morainedammed [307] followed by Erosion [265], other [96], and Ice-dammed [8] glacial lakes, respectively,” the space agency said.
It added that satellitederived long-term change analyses provide valuable insights for understanding glacial lake dynamics, which are essential for assessing environmental impacts and developing strategies for Glacial Lake Outburst Floods (GLOF) risk management and climate change adaptation in glacial environments.