近50 年气候变化背景下中国冰川面积状况分析

根据近年来中国典型区域冰川面积变化遥感监测数据,结合139 个地面站的气温、降水量与28 个探空站的0 ℃层高度气象资料,分析了近50 年气候变化背景下中国冰川面积状况。结果表明,研究区冰川面积从20 世纪60-70 年代的23982 km²减小到21 世纪初的21893 km²,根据冰川分布进行加权计算后冰川面积退缩了10.1%,对时间插补后得到1960 年以来的冰川面积年均变化率为0.3 % a^-1。就冰川面积变化的空间分布特征而言,天山的伊犁河流域、准噶尔内流水系、阿尔泰山的鄂毕河流域、祁连山的河西内流水系等都是冰川退缩程度较高的区域。近50 年中国冰川区夏季地面气温与大气0 ℃层高度均呈上升趋势,而降水量的增幅却相对轻微,增长的降水量不足以抵消升温对冰川的影响,气候变暖是影响冰川面积变化的主要因素。

Variation of Glacier Area in China against the Warming in the Past 50 Years

According to the remote sensing records on glacier area in the typical regions of China, as well as the meteorological data of air temperature and precipitation at 139 stations and the 0 ℃ isotherm height at 28 stations, the variation of glacier area in China and its climatic background in the past 50 years was discussed. The initial glacier area calculated in this study was 23982 km² in the 1960s/1970s, but the present area was only 21893 km² in the 2000s. The area-weighted shrinking rate of glacier was 10.1% , and the temporal-interpolated annual percentage of area changes (APAC) of glacier was 0.3% a^-1 since 1960. The high APAC was found at the Ili River Basin and the Junggar Interior Basin around the Tianshan Mountains, the Ertix River (a tributary of the Ob River) Basin around the Altay Mountains, the Hexi Interior Basin around the Qilian Mountains, etc. The retreat of glaciers was affected by climatic background, and the influence on glaciers of the slightly-increased precipitation is counteracted by the significant warming in summer.