Glacier area changes and its relation to climatological trends over Western Himalaya between 1971 and 2018

Abstract

Understanding the climatic complexity and its consequences on glacier health are of critical importance for the health of the Himalayan glacier and its contribution to the water budget. In this study, satellite datasets are used to estimate the glacier area loss, snow cover variability, and reanalysis data for climatic trends for four glacierised basins (Chandra, Bhaga, Miyar, and Parvati) of the Western Himalaya. In total, 257 glaciers covering a glacierised area of 1306 km², having a mean altitude of 5200 m asl, and an average slope of 18°, were analyzed using Corona (1971) and Sentinel (2018) satellite data. These glaciers have experienced a significant glacier area loss rate (0.2 km²a^-1) and an increase in the number of glaciers on account of fragmentation. Snow cover estimate during 2000–2019 using MODIS data showed no significant change or a slight decrease in snow cover area during the last two decades. However, the ERA-Interim reanalysis data revealed a systematic decrease in precipitation, an increase in temperature and an increase in liquid precipitation over the region during 1979–2018. The increased liquid precipitation possibly contributed to the faster melting of the snow and ice and consequently affected the glaciers’ health. The observed glacier fragmentation and glacier mass loss over the five decades and enhanced rainfall activity revealed a significant influence of climatic changes over the glacierised region in Western Himalaya.