1990-2015年喜马拉雅山东段中国和不丹边境地区冰川变化研究

利用Landsat影像，EDM影像等数据资料，使用遥感图像处理及目视解译方法提取了喜马拉雅山东段中国与不丹边境地区冰川从1990—2015年4期边界，研究其与气温降水变化关系，并选取特定冰川，对其表面流速进行估算。研究表明：1990—2015年，该地区冰川退缩速率达0.43%·a^-1，并且冰川年退缩率逐渐增大，表明冰川消融速度逐渐加快。该时段内，气温呈现明显上升趋势，导致了冰川的快速消融。通过对冰川表面流速的估算，得出中国与不丹边境地区研究选取的冰前湖对冰川流速具有促进作用，加速冰川消融。

Change of the modern glaciers in the eastern Himalaya near China and Bhutan border area from 1990 to 2015

Using the remote sensing technology and the visual interpretation,this paper extracted the glacier boundaries of four phases in the border area between China and Bhutan in eastern Himalaya based on the Landsat image and the DEM image from 1990 to 2015 to investigate the relationship between the glacier boundary change and climate change.The results show that from 1990 to 2015,the shrunk area of the glacier is 191.87 km2,and the glacier region retreat rate on average reaches to 0.43% per year.According to the time division,the average annual retreat rate of glaciers was increased gradually,indicating that the glacier ablation rate was gradually accelerated.The total area of glaciers in the region showed a decreasing trend,and the glacier area of different grades showed a trend of retreat.The distribution of glaciers is mainly north,north west and north east oriented while the main direction of retreat is east,southeast and northeast oriented.based on meteorological grid data,the change rates of air temperature and precipitation in winter and summer were retrieved by using the fitting operation on the air temperature and precipitation in different time periods.From 1990 to 2015,there was not obvious variation in precipitation while the temperature was significantly raised up.Therefore,it is believed that the main factor of glacier retreat is the rising temperature.Two specific adjacent glaciers were chosen to estimate the surface velocity using the CIAS software and it is found that the surface velocity of glacier is the fastest near the equilibrium line.The glacier flow rate was gradually slowed down to the highest altitude,and the glacier flow rate was the minimum.The glacier flow rate was gradually decreased along both sides of the glacier main stream.The surface velocity estimation shows that the chosen ice lake in the Bhutan region may speed up the melting of the glacier.There is a negative correlation between the change of glacier area and the change of temperature.There is a positive correlation between the change of ice front area and temperature change.