Analysis of differential glacier behaviour in Sikkim Himalayas in view of changing climate

Abstract

The assessment of temporal changes in glacier response due to climatic change is critical from the hydrological perspective. The present study aims to identify temporal changes in glacier response using area changes, retreat, and surface elevation changes. The Friedman test and Wilcoxon signed-rank test were introduced to identify the temporal changes in the parameters mentioned above for the entire Sikkim from a sample of 28 studied glaciers. The result shows the area changes lies between 0.044–0.462, 0.143–0.351, 0.083–0.685, and 0.157–1.39%y−1 between 1988–2000, 2000–08, 2008–14 and 2014–18, respectively. Further, the magnitude of deglaciation has increased after 2014 by 73%, 76%, and 100% compared to the third, second, and first timeframe. Likewise, retreat is 10.82 ± 3.53, 19.07 ± 4.19,13.32 ± 5.59,23.44 ± 5.3 my−1 between 1998–2000, 2000–08, 2008–14 and 2014–18, respectively in the sample glaciers. Additionally, surface elevation change shows a negative-accelerated trend in the sample glaciers from 0.15 to 1.92 my−1 to 0.88 to 2.52 my−1 between 2000–08 and 2008–18, respectively.