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本文采用1978、1991、2001和2015年的Landsat MSS、TM、ETM+和OLI遥感影像,通过遥感图像计算机辅助分类和目视解译等方法提取冰川边界,分析喀喇昆仑山克勒青河流域冰川在1978-2015年间的进退变化。结果表明:1978-2015年间研究区冰川面积由1821.70 km2减少至1675.92 km2,减少145.78 km2,占1978年冰川总面积的8.00%;冰川消融率较低,在气候变暖的背景下反而呈现出退缩速率由快变慢的趋势。研究区东南向冰川退缩率明显高于西北向,冰川退缩率随冰川规模的增大而减小。研究区内有27处冰川在1978-2015年间发生过特殊的前进现象,面积与长度显著增加。其中,木斯塔冰川西侧冰川末端在1996-1998年间前进速度为904 m/a,乔戈里冰川东侧冰川末端在2007-2009年间前进速度为446 m/a,5Y654D0097冰川末端在1978-1990年间前进速度为238 m/a,初步判定这三条冰川为跃动冰川。以10 a为滞后期分析研究区周边气象站点资料发现:研究区气温持续升高,降水量以1981年为分界点呈现“先减后增”趋势是冰川退缩速率减慢的原因之一;此外,亚大陆型冰川性质、巨大山势条件和高山冷储作用,也可能是冰川退缩幅度较小的原因。
In this paper, the Landsat MSS, TM, ETM + and OLI remote sensing images of 1978, 1991, 2001 and 2015 were used to extract the glacier boundaries by means of computer-aided classification and visual interpretation of remote sensing images. The glacier in the Keleqing River Basin Change between 1978 and 2015. The results show that the glacier area in the study area decreased from 1821.70 km2 to 1675.92 km2 from 1978 to 2015, decreasing by 145.78 km2, accounting for 8.00% of the total area of the glacier in 1978. The glacier ablation rate is relatively low, but retreat in the context of climate warming The trend of speed from fast to slow. The retreat rate of southeast glaciers in the study area is obviously higher than that in the northwest direction, and the retreat rate of glaciers decreases with the increase of glacier scale. In the study area, 27 glaciers have undergone special advancement during 1978-2015, with a significant increase in area and length. Among them, the glacier to the west of the Mupita Glacier advanced at a rate of 904 m / a between 1996 and 1998, the glacier east of the Jogori Glacier advanced at a rate of 446 m / a from 2007 to 2009, and the end of the 5Y654 D0097 Glacier was at 1978-98. The speed of advance was 238 m / a between 1990 and it was initially determined that these three glaciers were glaciers. Based on the 10-year lag analysis of the meteorological stations around the study area, it was found that the temperature in the study area continued to increase, and the precipitation decreased from 1981 to the demarcation point In addition, the continental glacier nature, huge mountain conditions and alpine cold storage may also contribute to the smaller extent of glacier retreat.