RECENT VARIATIONS OF THE INSUKATI GLACIER AND ADJACENT GLACIERS IN THE KARAKORAM MOUNTAINS
Zhang Xiangsong ( Lanzhou Institute of Glaciology and Cryopedology, Academia Sinica )
The changes in the positions of glacier termini in Karakoram Mountains for the Period of 1938-1973 present a very heterogeneous picture. Among 5 glaciers on the northwest of Qogir Feng, ( K2 ) 3 were retreating and 2 advancing. The Insukati Glacier with a length of 41.5 km is the longest in China.Though its lower reaches was covered by thick debris and its terminus stable in 1937-1968, yet the lowest position of bare ice stretched downward about 5 km. The Braldu Glacier located in Pakistan is 35 km long with its terminus covered by thick debris also. In 1937-1968, the position of the terminus was unchanged, Yet the lower limit of bare ice stretched 4 km downward and in 1968-1973 it developed to be having an eminent advance of terminus at a distance of 900 m. In contrast, the Skyang Glacier, K2 Glacier and Westmiyaz Glacier has retreated 4,250 m ( 137m/yr), 1, 700m ( 50m/yr) and 550 m(18m/yr) respectively. In addition, the Skyang Glacier had retreated again by 1,000 m(200m/yr)in 1968-1973. However, the recession rate of K2 Glacier is obviously reduced during the same period.