Water Resour. Res. 56, e2019WR026533 (2020)

Recent warming has caused glacier retreat in high-mountain Asia, with a corresponding increase in the size and number of glacial lakes dammed by glaciers or their debris. A glacial lake outburst flood (GLOF) occurs when these dams fail — for example, from melting, avalanches or upstream GLOFs. These events can have major downstream flooding impacts, and it is important to identify lakes at highest risk.

Credit: Dinodia Photos / Alamy Stock Photo

Saket Dubey and Manish Kumar Goyal of the Indian Institute of Technology Indore, India, use satellite data with elevation and flood models to gauge the hazard risk of 329 glacial lakes in the Indian Himalayas. The authors report a nearly 16% increase in lake area during 1993–2018, driven by one-fifth of identified lakes. They estimate around 22% of these lakes present a high or very high hazard risk due to both GLOF event likelihood and downstream impacts. An additional 59% show moderate risk. Such findings can help identify which lakes need further risk analysis and assist in regional climate change adaptation strategies.