The glaciers of the Hindukush-Karakoram-Himalayan (HKH) region consist of a huge amount of perpetual snow and ice. These glaciers are retreating in the face of accelerating global warming. Assessment of glacial hazard is carried out in this research using Satellite and Topographic data.
About 5,218 large and small glaciers cover a glaciated area of 15,040 km2 and ice reserves of 2,738 km3. The Shayok, Hunza and Shigar basins contain the major part (83%) of ice reserves.
This research presents the glacial hazard computations of largest glaciers of Pakistan. The results computed through study are compared with mathematical model of ice reserves and ice thickness which has supplemented their validity. The correlation of glacial hazard of these glaciers with average temperature rise of northern areas is confirmed.
The location of a site, snow cover/ melting behavior of the glacier, slope/ aspect of glacier, geo-morphology of the rocks and glacier dynamics are taken as indicators of disasters in the form of avalanches, snow/ land slide and glacier breakdown in the form of debris along with rock material.
The percentage degree of risk of glacial hazard is computed, which indicates that three out of world's seven largest glaciers have experienced degradation / volume loss over the years subjected to host of factors including anthropogenic activities.
For analysis, various methods of image classification in visible and thermal bands are used. The DEM is incorporated to detect the indicators of hazard as slope, orientation and glacier mass balance of the glaciers overlooking the settlements. The results show that settlements are found threatened by disastrous events of glacial activity which is further reconfirmed during the field visits.