Preliminary Study of Mass Balance on the Keqicar Baxi Glacier on the South Slopes of Tianshan Mountains

Since the late 1980s,there is a strong signal of climate shift from warm-dry to warm-humid in Northwest China.The mean air temperature of West China from 1987 to 2000 had increased by 0.7 °C as compared with the that from 1961 to 1986.With the rapid rising of air temperature,the annual mean precipitation during the period from 1987 to 2000 increased by 11% in northern Xinjiang and 32% in southern Xinjiang relative to that from 1960 to 1986 within the Tarim basin.In this paper,mass balance of the Keqicar Baxi Glacier in the Tarim River basin,Northwest China,is simulated under the condition of climate change,using a degree-day glacier mass-balance model.The glacier has detailed mass-balance measurement over the period 2003-2005.The modeling results are in good agreement with the measured variations in the mass balance changing with elevation during 2003-2005.The mean mass balance was-494 and-384 mm in the mass balance year of 2003-2004 and 2004-2005,respectively;compared to that in the 1970s,the equilibrium line altitude shifted up about 300 m.It can be seen that,though precipitation increases significantly,there is in the state of strong mass loss on the Keqicar Baxi Glacier due to the air temperature rising significantly.This study aims at providing a method for modelling the mass balance in the glacierised areas of the Tarim River basin,especially,in the non-monitored glacierised areas of Northwest China,as well as to assess the change in the cryosphere due to climate change.