Decadal Glacier Mass Balance over West Nyainqentanglha Range and Its Contribution to Nam Co Lake Increasing

摘要

Nyainqentanglha Range locates in the south-eastern center of Inner Tibetan Plateau. Glaciers in the whole range covered an area of 795 km2 in 2001 and locate at the transection zone between continental and maritime glaciers. Their melting at the northwestern slope feeds Nam Co Lake. Elevation of Nam Co Lake increased at a rate of 0.26m/a during 2003-2009 by ICESat laser altimetry monitoring which implied that retreating of glaciers within its drainage might accelerated. Previous study applied in situ observations on Zhadang Glacier's height change (-0.59m/a) and yielded during 1999 and 2010 glacier melting contributed 28.7% of the lake increasing (Lei et al., 2013). However, Zhadang Glacier only occupies less than 1% of the whole glacier area and almost bellows zero equilibrium line (ZEL), therefore the result should be biased and with large error. In this study, aiming on analyzing glacier melting's contribution to the endorheic lake increasing we applied DEM differencing method to quantify glacier mass balance at Nyainqentanglha Range by using SRTM and newly obtained bistatic TanDEM-X and TerraSAR-X images.