2000-2014年祁连山西段老虎沟12号冰川高程变化

祁连山冰川自1990s以来持续萎缩，冰川融水径流变化对邻近的干旱区水资源产生重要影响。以往遥感与实测研究显示祁连山西段老虎沟12号冰川面积减少、末端退缩、运动速度降低及平衡线高度升高。为了进一步验证老虎沟12号冰川变化规律，利用高分辨率TerraSAR-X/TanDEM-X微波影像数据，与SRTM-C DEM进行差分干涉，得出老虎沟12号冰川2000-2014年高程年平均变化值为（-0.29±0.09）m·a^-1。为了验证遥感观测结果，利用RTK-GPS对老虎沟12号冰川表面进行测高，并与SRTM-C DEM上相应点的高程值进行比较，计算测量点的高程年变化值，结果显示两种方法获得的年平均变化值之间具有很好的正相关性，表明利用TerraSAR-X/TanDEM-X微波影像数据及差分干涉技术监测祁连山冰川高程变化具有较好的可行性。

Elevation change of the Laohugou Glacier No.12 in the western Qilian Mountains from 2000 to 2014

Glaciers in the Qilian Mountains have retreated since the 1990s,and the glacier ablation has great effect on the water resources in the add Hexi corridor.The past studies based on remote sensing technology and field investigation has showed that the glacierized area had decreased,with terminus shrink upward,flow velocity slowing down and the equilibrium line altitude rising.In order to investigate the glacier elevation change by remote sensing technology,the interferometric phase of TerraSAR-X/TanDEM-X (TSX/TDX) subtracted the interferometric phase simulated from the co-registered SRTM-C DEM using the satellite geometry and baseline model of the TSX/TDX,the resulted differential interferometric synthetic aperture radar (DInSAR) phase was converted to the height difference.The thinning rate of the Laohugou Glacier No.12 had been (0.29 ± 0.09)m · a-1 from 2000 to 2014.In an expedition in 2016,the elevation of the ablation area was measured using the Real Time Kinematic Global Position System (RTK-GPS),and the change in elevation was calculated via compadsons with the elevation of the matching points on the SRTM-C DEM acquired in 2000.These values were used to validate the DInSAR results and found a correlation coefficient of 0.6.The microwave remote sensing images of TerraSAR-X/TanDEM-X and differential interferometry technology can be applied to study glacier elevation change in the western Qilian Mountains.