1960-2020年高加索山地冰川变化研究

Glacier variations in the Caucasus Mountains from 1960 to 2020

冰川融水是高加索重要的淡水资源,对区域农业灌溉、水利发电等具有重要意义。本文基于Landsat影像和Sentinel影像对的相干系数图,结合GLIMS冰川编目以及WGMS冰川物质平衡资料,研究了1960-2020年高加索山地冰川变化的时空格局。研究结果表明,2020年高加索山共分布有冰川1 912条,总面积(1 087.36±66.44)km^(2)。1960-2020年冰川面积共计萎缩(587.36±98.66)km^(2)[(35.07±5.89)%],年均萎缩率达到(0.58±0.10)%·a。1960-1986年、1986-2000年、2000-2020年高加索冰川的面积萎缩率分别为(0.44±0.20)%·a、(0.66±0.77)%·a和(0.96±0.31)%·a,表明近60年以来高加索冰川处于加速退缩状态。对物质平衡资料的分析结果显示,近60年来高加索山脉的Djankuat和Garabashi冰川均处于强烈的负平衡状态,并在2000年后物质亏损明显加速。对气候资料的分析结果则表明气温的加速上升是近几十年来高加索山地冰川加速退缩的主要原因。

Glacial meltwater is an important freshwater resource in the Caucasus and is important for regional irrigation and hydroelectricity generation. This paper analyses the spatial and temporal patterns of glacier change in the Caucasus Mountains from1960 to2020 based on Landsat images,coherence images from Sentinelimage pairs,GLIMS glacier inventory and WGMS glacier mass balance data. The results of the study show that in2020 there were1912 glaciers in the Caucasus Mountains,with a total area of(1 087.36±66.44)km^(2). The total glacier area shrank by(587.36±98.66)km^(2)(35.07±5.89%)between1960 and2020,with an average annual shrinkage rate of(0.58±0.10%)·a. The area shrinkage rates of Caucasian glaciers for1960-1986,1986-2000 and2000-2020 are(0.44±0.20%)·a,(0.66±0.77%)·aand(0.96±0.31%)·a,respectively,indicating that Caucasian glaciers in a state of accelerated retreat over the last60 years. Analysis of mass balance information shows that both the Djankuat and Garabashi glaciers in the Caucasus have been in a strong negative equilibrium for nearly60 years,with a significant acceleration of mass deficit after2000. Analysis of climate data suggests that the strong warming is the main reason for the accelerated retreat of glaciers in the Caucasus mountains in recent decades.