Decadal Changes in Glaciers in the Alaknanda Basin (Uttarakhand) Under Warming Climate

Glaciers are essential for regulating water resources and climate patterns, making their study crucial for understanding the effects of climate change on mountain ecosystems. This research presents a comprehensive analysis of glacier coverage and recent changes within the Alaknanda Basin in Central Himalaya, alongside temperature trends over two decades, as key indicators of ongoing climate variations. Remote sensing data, including satellite imagery from sources such as LANDSAT (OLI) and ETM+, were utilized for the years 2000, 2013, and 2020. In the Alaknanda Basin, a total of 301 glaciers were identified and categorized based on their size and morphology, with 220 small/hanging glaciers, 76 medium-sized glaciers, and 6 large (valley) glaciers. Furthermore, this study investigates patterns of glacier retreat observed in the region during 2000, 2013, and 2020. The analysis of these retreat trends provides valuable insights into the speed and extent of ice loss in the area. The total glacier area decreased from 7.49 sq. km between 2000 and 2013 to 3.88 sq. km between 2013 and 2020, with average retreat rates of 4.657803 m/year from 2000 to 2013 and 13.23608 m/year from 2013 to 2020. These findings emphasize the complex relationship between glacier retreat and the expansion of lakes, with potential consequences for downstream ecosystems, particularly in the context of glacial lake outburst flood (GLOF). The study also reveals a noticeable and consistent increase in temperature, aligning with broader global climate change trends, which contribute to glacier retreat. Ultimately, this research advances our knowledge of glacier dynamics with reference to climate change and enhances the field of glacier research.