Inventory and Monitoring of Glacial Lakes in Himalayan Region Using Geo Spatial Technologies

Abstract

The glaciers consist of a huge amount of perpetual snow and ice and are found to create many glacial lakes. Abrupt release of large amounts of stored water in these lakes results in a catastrophic outburst flood. Several such incidents of flash floods were reported all over the world and also in Himalayas region of India causing huge economic losses. To mitigate the impact of these types of events, prior knowledge about the location, the areal extent and the volume of these lakes is very essential. The location of these glacial lakes in rugged and remote terrain makes it difficult to monitor them manually. Remote sensing plays a vital role in creating inventories and monitoring of the glacial lakes quickly and accurately due to wider coverage and repetivity. The satellite images provide greater details for the evaluation of physical conditions of the area. This paper discusses a case study on the inventory and monitoring of glacial lakes or water bodies in Sutlej basin using satellite remote sensing. The study area is Sutlej basin from its origin to Bhakra dam situated in Western Himalayas. This basin is highly rugged terrain with abundant natural water resource in the form of snow pack and glacial lakes. The Inventory of glacial lakes or water bodies was done using Indian Remote Sensing LISS-III data and monitoring using AWiFS data. A total of 197 lakes or water bodies have been identified whose water spread area is greater than 2 ha. 40 lakes with area greater than 10 ha were monitored during June–August 2007. The change in water spread area statistics was observed in 23 lakes with a variation of greater than ±10%.