Publication

Abstract : Glacial lake outburst floods (GLOFs) are a hazard commonly reported in the glaciated terrain of the Hi- malaya. Glacier lakes can form if the glaciers retreat and the bottom topography overdeepens. We have adopted a technique to estimate the depth and volume of lakes using parameters such as glacier surface ve- locity, slope and laminar flow of ice. The technique has been automated using Python programming lan- guage. The method was applied in the Sikkim Hima- laya to map potential lake sites and also to predict further expansion of existing glacier lakes. Studies were carried out for ten glaciers in the Tista river ba- sin. The analysis suggests nine potential lake sites, in- cluding further expansion of four existing glacier lakes. To validate the results, the model lake boun- dary in 2001 was compared with the satellite-observed value of 2015 and field measurements made at the South Lhonak lake. The volume of the South Lhonak lake (in 2015) was estimated as 60 ± 10.8 million m 3 ; with prolonged retreat of the glacier, the lake is likely to expand to a maximum volume of 90 ± 16.2 million m 3 . The above technique can provide new information to planners, leading to a more realistic approach in understanding the disaster potential of glacier lakes.