Unveiling the footprints of Climate Change: A Comprehensive Study of Spatio-temporal Variability of Glaciers in Shigar Basin, Pakistan

Abstract

HKH region is often referred to as “Third Pole”, due to the quantity of snow and ice it stores and the freshwater it provides to community. Glaciers are sensitive to climate change, and they are the first one to respond. Central Karakoram region is part of HKH and Shigar basin is one of the important basins in this region due to its geo political location and many of the highest mountain peaks on the earth. Therefore, the impact of climate change on the glaciers of Shigar basin were studied for better sustainable management of water resources and future predictions regarding any risk. In this contribution, total 448 glaciers were delineated in Shigar basin and assessed from 1990 to 2022 using Sentinel, Landsat Operational Land Imager (OLI), the Thermal Infrared Sensor (TIRS) and ALOS PALSAR Digital Elevation Model. The total glacier area increased from 2408.3 ± 60 km² in 1990 to 2425.2 ± 60.2 km² in 2022 with an increase of about 16.9 km². 33% of the glaciated area is covered with supraglacial debris. Two case studies were also discussed in this study which can pose threat in near future, one is the Chogo Lungma glacier where landslide can block the flow of river and form a lake, and other one is Biafo glacier, where narrow valley exist with river flowing in between just after the terminus of Biafo glacier and any abrupt surge can form potential lake, the river flows from Baltoro glacier which is one of the largest glaciers in the region. Overall, glaciers of Shigar basin were found out to be stable in the study period, climate analysis of the basin and adjoining region was also carried out. The trend obtained from the available data exhibited a considerably stable behaviour with indicators varying between the set extremes. Though some anomalies are visible but are much less likely to occur and are short lived. However, there is a dire need to install meteorological stations at higher altitudes and acquisition of field data is important for future study of these complex water bodies.