中文摘要：

度日模型是估算冰川消融的一种简单而有效的方法,度日因子是该模型的重要参数,反映了单位正积温产生的冰雪消融量,其时空变化特征对不同模型模拟冰雪消融过程的精度有较大影响.根据乌鲁木齐河源1号冰川22a的物质平衡花杆观测资料和大西沟气象站气象资料,分析了该冰川度日因子的时空变化规律及其影响因素.结果表明：时间尺度上,融雪度日因子年际变化不大,融冰度日因子随年际变化有增加趋势,且这种增加趋势在冰川中下部要比冰川上部明显;空间尺度上,随海拔升高,度日因子具有明显的下降趋势;2000-2004年与1983-1989年相比,1号冰川东、西支夏季物质平衡变化量分别为-240mm和-290mm,其中气候变化直接引起的变化量为-206mm和-175mm.

英文摘要：

The degree-day model is one of the simplest and significant methods to estimate glacier ablation. Degree-day factor is an important parameter of degree-day model,showing the glacier-snow ablation for a unit positive degree-day. Temporal and spatial variations of a degree-day factor have great impacts on the accuracy of snow or ice melt modeling.In this paper,the spatial-temporal variation characteristics of the degree-day factors and the influencing factors are analyzed according to the mass balance observed by stakes on the Glacier No.1 and the weather data of Daxigou Meteorological Station. The study shows that：1） temporally,the annual change of degree-day factors for snow ablation is not obvious,whereas the annual change of degree-day factors for ice ablation is increasing and the increasing trend in the lower part is more significant than that in the upper of glacier; 2） spatially,the degree-day factors obviously decrease with attitude;3） the mean summer mass balance variation was -240 mm and -290 mm in the east and west branch,respectively,of the Glacier No. 1 during 2000-2004,as compared with that during 1983-1989,among them -206 mm and -175 mm,respectively,was directly caused by climate change,and -34 mm and -115 mm,respectively,indirectly caused by ice-surface feature change.