Glacial Lakes in the Himalayas: A Review on Formation and Expansion Processes

In the recent several decades, glacial lakes have been expanding at the terminus of debris-covered glaciers associated with glacier shrinkage in the Himalayas. Accordingly, glacial lake outburst floods (GLOFs) have become serious natural disasters in the Himalayas. Bathymetrical surveys have been carried out at several glacial lakes, and the relationship between the lake area and water volume has been illustrated. At the initial stage, several small lakes are distributed near the glacier terminus, and then they coalesce and become one large lake, and finally, the large lake expands rapidly through calving of the glacial front. Surface inclination, surface velocity and surface lowering of glaciers are significant indicators of glacial lake expansion. Future prediction of topographical changes in debris-covered glaciers is important in forecasting the formation and expansion of glacial lakes.