Investigating the Evolution of Imja Lake and Imja-Lhotse Shar Glacier with a Debris-Covered Melt Model and Lake Expansion Model

Abstract:

The melt of glaciers in the Himalayas over the past half-century due to global temperature increase has led to the formation of many glacial lakes. These lakes typically form on the tongue of stagnant debris-covered glaciers with gentle slopes where there is significant amount of differential melting due to the spatial variation of debris thickness. Once the lake develops, the water acts as a heat sink thereby increasing the rate of mass loss as the lake expands rapidly due to calving retreat. Imja Lake is an excellent example of a glacial lake that developed in the 1950’s and has been undergoing rapid expansion due to calving retreat for many decades. This study seeks to use a debris-covered melt model in conjunction with a lake expansion model to investigate the evolution of Imja Lake and Imja-Lhotse Shar glacier.