2008—2018年中国冰川变化分析

Analysis of glacier changes in China from 2008 to 2018

调查冰川资源的分布与变化,对区域乃至全球的自然环境与经济社会发展都具有十分重要的意义。基于315景Landsat 8 OLI遥感影像,结合中国第二次冰川编目数据与Google Earth软件,通过人工目视解译等方法调查了2018年中国冰川的分布与变化。结果表明:中国现存冰川53238条,总面积为(47174.21±19.93)km^(2),72%的冰川面积<0.5 km^(2),规模在1~32 km^(2)的冰川的面积占中国冰川总面积的60%。2008—2018年,中国冰川总面积减少1393.97 km^(2),面积变化率为-0.43%·a^(-1)。冰川面积变化率表现出明显的空间差异,面积退缩最快的是冈底斯山,达-1.07%·a^(-1);最慢的是羌塘高原,为-0.05%·a^(-1)。坡度上,各山系之间的冰川面积变化率差异较为明显。超过70%的山系位于正东和东南方向的冰川面积退缩快,2008—2018年退缩率为-5.0%;正北方向的冰川面积退缩相对缓慢,同时期退缩率为-3.8%。气温和降水变化率差异以及海拔、坡度、坡向等地形差异,共同影响中国冰川的变化。

For the regional and global natural environment and economic and social development,it is of great significance to investigate the distribution and changes of glacier.In this paper,the boundary of the existing gla⁃ciers in China was achieved by manually visual interpretation guided by the methodology of the Second Chinese Glacier Inventory based on 315 Landsat 8 OLI remote sensing images,global watershed data and Google Earth in 2018.The state and area changes of glacier were examined during 2008—2018 compared to glacier boundary from the Second Chinese Glacier Inventory.The results show that there are 53238 glaciers with a total area of(47174.21±19.93)km^(2)in China currently,72%of the glaciers in China are less than 0.5 km^(2),and the area of glaciers with a scale of 1 to 32 km^(2)accounts for 60%of the total area of Chinese glaciers.From 2008 to 2018,the total area of glaciers in China has decreased by 1393.97 km^(2),and the area change rate was-0.43%·a^(-1).The area change rate of glacier shows obvious spatial heterogeneity.The fastest rate of glacier area retreat is the GangdisêMountains,reaching-1.07%·a^(-1);the slowest is the Qiangtang Plateau,with-0.05%·a^(-1).In terms of slope,the difference in change rate of glacier area between various mountains is relatively obvious.During 2008—2018,more than 70%of the mountains are located in the east and southeast with a fast average retreat ratio,which is-5.0%,and the retreat of glaciers in the north direction is relatively slow,with a retreat ratio of-3.8%during the same period.Differences in temperature and precipitation change rates,as well as differences in alti⁃tude,slope and aspect,affect glacier changes in China together.