Frontal recession of Parkachik Glacier between 1971-2015, Zanskar Himalaya using remote sensing and field data

摘要

Parkachik Glacier is located in the Suru sub-basin of the Upper Indus River, Zanskar Himalaya. The Glacier has been analysed using Corona KH-4B (1971), Landsat-TM (1999), field survey (2015), Google Earth (TM) (2015) and ASTER GDEM (2015) for frontal recession and area changes. Overall, from 1971 to 2015, the Glacier has retreated by 127 +/- 0.09 m i.e. (0.75 +/- 0.07%) at a rate of 2.9 +/- 0.004 ma(-1) with a simultaneous decrease in area from 49.5 to 48.8 km(2) i.e. 740 +/- 0.7 m(2) (1.5 +/- 0.09%) at a rate of 74 +/- 0.7 m(2)a(-1). However, during recent decade (1999-2015), the rate of glacier recession of 3.9 +/- 0.004 ma(-1) with a corresponding area loss of 500 +/- 0.74m(2) (1 +/- 0.1%) was higher than the retreat rate of 2.3 +/- 0.001 ma(-1) and an area loss of 240 +/- 0.02m(2) (0.48 +/- 0.08%) during 1971-1999. In the field, the evidences of glacier recession are present in the form of separated dead ice blocks from the main Glacier, recessional dumps/moraines, active ice calving activity and a small proglacial pond/lake at the terminus/snout of the Glacier. However, the recession over the studied period has been very slow and is controlled by its topographic configuration, particularly the large altitudinal range (6030-3620 m), almost northerly aspect and steep slope (average similar to 30 degrees).