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基于1970年冰川编目数据、1999年和2011年ETM+数据,利用决策树分类和目视解译方法提取了念青唐古拉山东段则普乡地区则普冰川、则普北冰川和央别贡冰川边界,并结合丁青和波密站的气温、降水量资料分析研究区冰川变化原因。结果表明:1970-2011年冰川总体呈退缩状态,冰川面积共减少81.51km2,各冰川在1970-1999年退缩速率均大于1999-2011年,冰川退缩具有减缓趋势;温度升高是近40a来冰川退缩的主导因素,而1990-2001年降水增加是冰川减缓退缩的主要原因。冰川相对变化率随冰川规模增大而减小,即小规模冰川对气候变化响应更为敏感。依据气象资料,对研究区未来十几年冰川变化情况作初步预测,认为研究区冰川将呈加速退缩趋势。
Based on the data of glacier inventory in 1970, ETM + data in 1999 and 2011, we extracted the Jipu glacier in Zebu plain in the eastern segment of the Nyainqentanglha Mountain using the decision tree classification and visual interpretation method, then the boundary between the Pubei glacier and the central Beigong glacier, Based on the data of temperature and precipitation in Dingqing and Bomi stations, the causes of glacier changes in the study area are analyzed. The results show that the glacier generally retreated from 1970 to 2011, with a total decrease of 81.51km2 in glacier area. The retreat rates of glaciers from 1970 to 1999 were all greater than those from 1999 to 2011, with the retreat of glaciers slowing down. The temperature rise was nearly 40 years The main reason for the retreat of glaciers is the increase of precipitation in 1990-2001. The relative change rate of glacier decreases with the increase of glacier, that is, the small-scale glacier is more sensitive to the climate change. Based on the meteorological data, the preliminary prediction of the glacier changes in the study area in the coming ten years is made, and the glaciers in the study area will show an accelerated trend of withdrawal.