1959-2008年新疆阿尔泰山友谊峰地区冰川变化特征

Glacier changes in Youyi Area in the Altay Mountains of Xinjiang during 1959-2008

利用1959年地形图、2008年ASTER数字遥感影像及数字高程模型,在地理信息系统技术支持下分析了新疆阿尔泰山友谊峰地区冰川的变化特征。研究表明:1959-2008年该区冰川整体呈萎缩趋势,且变化幅度相对较大。相对于1959年,2008年冰川面积和数量分别变化-32.5%和-27.9%。其中,小于1 km2的冰川面积平均变化率为-66.7%,面积小于0.5 km2的冰川面积变化率大于-70%,面积大于1 km2以上的冰川面积变化率为-35.0%,1～5 km2的冰川面积变化率为-27.9%。冰川末端平均后退253 m,末端退缩比例为-18.3%,且南坡冰川末端变化率大于北坡。分析发现,研究区冰川面积亏损较大主要缘于该区小冰川分布数量较多(面积小于1 km2的冰川数量达75%),对气候变化的响应较为敏感。

Research on glacier change has been limited in Chinese Altay Mountains among the border of China, Russia and Mongolia, despite the fact that the number of glaciers in the Altay Mountains is less among all mountain ranges in China, and the glaciers in this region provide very important water resources for local economic develop- ment and drinking water for man use. Most of the research on glaciers in China is in Tianshan Mountains, Qinghai -Tibet Plateau and Qilian Mountains, but not in Altay Mountains. During the past several decades, most glaciers are in a state of rapid retreating due to climate warming. The glaciers of Youyi in the Altay Mountains were selected as the study area. Based on 1：50 000 topographic maps in 1959, ASTER remote sensing data in 2008 and digital information systems technology. The results indicate that the amplitude of the whole change of glaciers in the Youyi Area is large and glaciers in this area have retreated rapidly during the study period from 1959 to 2008. In the stud- y period, the total area and number of the investigated glaciers （226） have reduced by 32.5% and 27.9%. At the same time, the results showed that glaciers average rate of change with area less than 1 km2 is - 66.7 % and glac- iers average rate of change with area less than 0.5 km2 is -70%. Moreover, those glaciers with area from 1 to 5 km2 have reduced by 27.9%. The paper analyzed the reasons of the large change rate of glaciers, and the results indicate that the large change rate of glaciers is caused by the large proportion of small glaciers, whose glaciers smaller than 1 km2 account for nearly 75% in the investigated glaciers. Moreover, the results show that the larger the glaciers are, the higher the amplitude of the ablation is, but the reduced rate is lower. And those glaciers have the highest degree of response to climate change. The glaciers retreated by 253 m at a rate of 18.3%. The glacier changes exhibited obvious spatial differences, indicating that the reduction rate of glaciers to the south slope of the Youyi Area was larger than that of the north.