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Glaciers in the western Nyainqentanglha Range are an important source of water for social and economic development. Changes in their area were derived from two Chinese glacier inventories; one from the 1970 1:50,000 scale Chinese Topographic Maps series and the other from Landsat TM/ETM+ images acquired in 2009. Analyses also included boundaries from 2000 and 2014 Landsat TM/ETM+ images. A continuing and accelerating shrinkage of glaciers occurred here from 1970 to 2014, with glacier area decreasing by 244.38 ± 29.48 km~2(27.4% ± 3.3%)or 0.62% ± 0.08% a~(–1). While this is consistent with a changing climate, local topographic parameters, such as altitude, slope, aspect and debris cover, are also important influences. Recession is manifested by a rise in the elevation of the glacier terminus. The shrinkage of glaciers with NE, N and NW orientations exceeded that of other aspects, and glaciers with SE and S orientations experienced less shrinkage. Changes in the average positive difference of glaciation(PDG) show that the western Nyainqentanglha Range has unfavorable conditions for glacier maintenance which is being exacerbated by a warming climate since 1970.
Glaciers in the western Nyainqentanglha Range are an important source of water for social and economic development. Changes in their area were derived from two Chinese glacier inventories; one from the 1970 1: 50,000 scale Chinese Topographic Maps series and the other from Landsat TM / ETM + images acquired in 2009. Analyzes also included boundaries from 2000 and 2014 Landsat TM / ETM + images. A continuing and accelerating shrinkage of glaciers occurred from 1970 to 2014, with decreasing glacier area by 244.38 ± 29.48 km ~ 2 (27.4% ± 3.3% ) or 0.62% ± 0.08% a ~. While this is consistent with a changing climate, local topographic parameters, such as altitude, slope, aspect and debris cover, are also important influences. the elevation of the glacier terminus. The shrinkage of glaciers with NE, N and NW orientations exceeded that of other aspects, and glaciers with SE and S orientations experienced less shrinkage. Changes in the average positive dif ference of glaciation (PDG) show that the western Nyainqentanglha Range has unfavorable conditions for glacier maintenance which is being exacerbated by a warming climate since 1970.