黄河源区阿尼玛卿山典型冰川表面高程近期变化

Recent surface elevation changes of three representative glaciers in nyêmaqên Mountains,source region of Yellow River

阿尼玛卿山位于青藏高原的东缘,是黄河源区冰川分布比较集中的区域。该区域的冰川物质平衡变化研究对于冰川水资源评估及冰川对气候变化响应研究具有重要借鉴意义。通过TerraSAR-X/TanDEM-X数据的干涉测量方法获得阿尼玛卿山区冰川的高分辨、高精度的数字高程模型(DEM),与SRTM DEM进行差分获得该区域冰川2000年至2013年间的表面高程变化。对比发现:近13 a来该区域典型大冰川表面高程整体均有所下降,唯格勒当雄冰川末端区域冰川表面高程平均下降(4.16±3.70)m,冰舌中部表面高程有所增加,冰川末端区域表碛覆盖范围有所增加;哈龙冰川表面高程从末端往上呈递减下降的趋势,平均下降(8.73±3.70)m;耶和龙冰川表面平均下降了(13.0±3.70)m,但从冰川末端往上1.6 km区段表面高程平均增加约25 m,冰舌中部表面高程下降明显,对比冰川编目数据、Landsat TM图像可知,该冰川在2000年至2009年间发生过跃动,冰川末端位置前进了约500m。总体来说,即使存在个别冰川前进现象,该区域冰川在近13 a间仍处于退缩状态。

Anyemaqen Mountains is located in the eastern part of the Tibetan Plateau,where there are many glaciers. The glacier change has an important significant in glacier response to climate change and for glacier meltwater resource accessment. In this article,interferometry of Terra SAR-X/TanDEM-X with bistatic mode was employed to retrieve high resolution and high precision Digital Elevation Models（DEM）. Elevation changes of three representative glaciers between 2000 to 2013 were calculated by differential methods with SRTM DEM covered. It was found that surface elevation of the three glaciers has decreased as a whole in recent 13 years. In the Weigele Dangxiong Glacier,the surface elevation has decreased（4. 16 ± 3. 70） m in average,mostly near the terminus; the debris covered area has expanded; the surface elevation has increased in the middle part of the glacier tongue. In the Halong Glacier,surface elevation has decreased（8. 73 ± 3. 70） m in average from terminus to accumulation zone. In the Yehelong Glacier,surface elevation has decreased（13. 0 ± 3. 70） m in average. However,from terminus up to 1. 6 km,the surface elevation has increased 25. 0 m in average,then has decreased clearly in average up to 1. 6 km along the main flowline. Comparison between glacier outline of Chinese Glacier Second Inventory and Lansat 7/8 image found that terminus of the Yehelong Glacier had advanced about500 m,indicating a fast advance or surge between 2000 and 2009. Thus,the conclusion can be drawn that the glaciers in Anyemaqen Mountains had retreated as a whole from 2000 through 2013 with some advances.