Glacial lakes and its expansion in the north-central Bhutan and Kulha Kangri massif, Eastern Himalaya

Abstract

A great number of the glacial lakes have appeared in many mountain areas of the world during the last half-century due to global warming. Severe floods have been caused by frequent outbursts from the glacial lakes. These glacial lake outburst floods (GLOF) have also occurred in the Himalayan mountains (e.g., Vuichard and Zimmermann 1987, Xu and Feng 1994), including Bhutan Himalaya. The last outburst flood in Bhutan, which originated from Lugge Glacial Lake in October 1994, caused damage to property along the river with the loss of more than 20 lives (Watanabe and Rothacher 1996). Hence, investigation of the glacial lakes is necessary for disaster prevention in Bhutan and the downstream region. Geological Survey of Bhutan (1999) and Mool et al. (2001) made the inventory of the glaciers and glacial lakes in Bhutan. Ageta et al. (2000) and Komori et al. (2003) obtained the expansion records of the lakes in Bhutan. However, much remains to be established about the spatial and temporal variation of glacial lakes not only in Bhutan but also the other Himalayan mountains. The present study revealed the current condition of glacial lakes and its secular variations during the last 45 years.