Inventory of Glacial lakes in Hunza River Basin by Exploring Satellite Observations

Abstract

Northern latitudes of Pakistan are warming at faster rate as compared to the rest of the country. It has induced irregular and sudden glacier fluctuations leading to the progression of glacial lakes, and thus enhancing the risk of Glacier Lake Outbursts Floods (GLOF) in the mountain systems of Pakistan. Lack of up-to-date inventory, classification and susceptibility profiles of glacier lakes and newly formed GLOFs, are few factors which pose huge hindrance towards disaster preparedness and risk reduction strategies in Pakistan. This study aims to bridge the existing gap in data and knowledge by exploiting satellite observations and efforts are made to compile and update glacier lake inventories. GLOF susceptibility assessment is achieved by using Analytical Hierarchy Process (AHP), a multicriteria structured technique based on three susceptibility contributing factors like geographic, topographic and climatic. A total of 294 glacial lakes are delineated with total area of 7.85 ± 0.31 square kilometers as of the year 2018. The distribution of glacial lakes is vastly skewed towards more glaciated region of Hunza River Basin. Analysis has identified six glacier lakes as potential GLOF and met the pre-established criteria of damaging GLOFs. The historical background of earlier GLOF events are utilized to validate the anticipated approach and found this method appropriate for first order detection and prioritization of potential GLOFs in Northern Pakistan.