Study on mass balance and sensitivity to climate change in summer on the Qiyi Glacier, Qilian Mountains

摘要

Based on the glacier mass balance and meteorological data of air temperature and precipitation on the Qiyi Glacier from June 30 to September 5,2010,we used a degree-day mass balance model to simulate the change of mass balance during this period.Our results indicate that the current value of the mass balance is 856.2 mm w.e.Subjected to the strong influences of air temperature and precipitation,the mass balance process can be divided into three stages:accumulating exiguously → melting intensively → melting exiguously.The variation trends of the mass balance according to the degree-day mass balance model and the observed values are similar and wholly reflect the spatial distribution characteristics of the glacier mass balance,which increases with the increase of altitude.Our experiment on climate sensitivity of the mass balance showed that mass balance was very sensitive to the change of temperature;air temperature is the key factor which influences mass balance;and a slight increase in precipitation will have a negligible effect on mass balance when the air temperature increases continuously.