【摘要】 采用地形图、航空摄影相片、中巴资源卫星和Landsat TM数字影像, 对青藏高原东南部岗日嘎布山区20世纪初以来的冰川变化进行了研究, 分析了该地区冰川对 20 世纪后期全球变暖的响应.结果表明: 20世纪初期至1980年, 研究区的冰川基本处于退缩状态, 期间冰川面积减少了13 8%, 储量减少了9 8%, 储量减少量相当于249 2×108 m3水当量, 因冰川萎缩导致其对河川径流的调节作用减弱了一半左右. 1980年以来, 本区气候表现出升温和降水增加, 在此气候变化背景下, 冰川总体呈面积减小的退缩状态, 但有一定数量的冰川处于前进之中, 这可能与不同规模冰川对气候变化的响应特点和响应时间有关.更多还原

【Abstract】 Recent studies indicate that most alpine glaciers around the world have retreated during the past decades under global warming. In this study, a region with temperate glaciers, mainly influenced by the Indian Monsoon, is selected to examine the present status of glaciers under a warming background. Aerial photos, topographical maps, China-Brazil Earth Resource Satellite （CBERS, with resolution of 19 m and acquired on Jan. 30 2001） and Landsat Thematic Mapper （TM, acquired on Oct. 26 1999） images are used. Aerial photos are mainly applied for identifying the end and lateral moraines formed at the end of the Little Ice Age, which was thought to occur in the mid-1920s. CBERS and Landsat TM images geometrically corrected and co-registered to 1∶{100 000} topographical maps are applied to extract the information of glacier distribution at the time the imageries acquired. It was concluded that the measured 102 glaciers in the region have all in retreat from the 1920s to 1980, with a total areal and ice volumetric decreases of 47^9 km² and 6^95 km³. It is estimated that all glaciers in the region have lost 13^8% of their total area and 9^8% of the total ice volume during the same period. Since 1980, glaciers in the region have also experienced an ice mass loss process in general, according to the data of 88 glaciers with a total area of 797^78 km² from topographical maps in 1980 and the CBERS image in 2001. About 60% of these glaciers have been losing their mass and other glaciers have advanced. Analysis indicates that glacier retreat has significantly impacted glacial meltwater runoff, resulting in 50% decrease of runoff from 1915 to 1980. The trend of glacier retreat and climatic warming during the last century, especial during the past two decades, shows a possibility that mass loss of glaciers in the region will be accelerating in the future.更多还原