近50年丝绸之路经济带中国境内冰川变化

冰川是丝绸之路经济带中国境内重要的水资源,对该区农业建设和经济发展至关重要。基于修订后的中国第一次冰川编目数据和最新发布的第二次冰川编目数据,对丝绸之路经济带中国境内冰川变化进行分析。结果表明:(1)丝绸之路经济带中国境内现有冰川22523条,面积25516.80 km^2,冰储量约2592.85 km^3,分别占我国冰川相应总量的46.37%、49.22%和57.39%,其中新疆维吾尔自治区冰川储量最为丰富,共计2366.25 km^3。(2)丝绸之路经济带中国境内冰川以面积<0.5 km^2的冰川数量最多,共计15519条,占冰川总数量的68.90%;面积则以介于1~5 km^2冰川为主,共计6833.71 km^2,占冰川总面积的26.78%;各山系的冰川退缩海拔高度不同,面积减少速度在各个高度带均有差异。(3)近50年间丝绸之路经济带中国境内冰川面积共减少4527.43 km^2,变化百分比为-20.88%,有3114条冰川消失,冰川冰储量损失约419.35 km^3。(4)丝绸之路经济带中国境内冰川变化整体呈现自西向东加快趋势,减少速率整体上有自西南向东北加快趋势;冰川朝北消失数量大于朝南消失数量,东北方向面积减少最多,东南方向面积减少最快。(5)近50年间丝绸之路经济带中国境内有暖湿化趋势,冬季气温升高速率大于夏季且降水增加幅度小于夏季的气候组合模式,不利于冰川的积累从而导致冰川退缩;冰川发育规模对冰川退缩也有一定影响,但各山系冰川变化驱动力具有空间差异。

Glacier changes along the Silk Road Economic Belt in China in the past 50 years: Based on the revised First and Second Chinese Glacier Inventory

Glaciers, important water resources in northwestern China, are of great importance to the agricultural construction and economic development of the Silk Road Economic Belt. Based on the revised First (1956s-1983s) and the newly released Second Chinese Glacier Inventory (2005s-2010s), glacier changes in the glaciated regions along the Silk Road Economic Belt in China were analyzed. The results show that: (1) Glaciated areas along the Silk Road Economic Belt in China contained 22523 glaciers, covering an area of 25516.80 km² and ice volume of 2592.85 km³, respectively, accounting for 46.37%, 49.22% and 57.39% of the total glacier area accordingly, and among which the total amount of glacier resources in Xinjiang was the largest. (2) While most glaciers were small (15519 glaciers, 68.9% was smaller than 0.5 km²), some larger ones (totally 6833.71 km², with each having 1.0 and 5.0 km²) covered 26.78% of the total glacier area. The altitude of concentrating regions in the glacier retreat of each mountain range was different, and the rate of area reduction differed in each height zone. (3) During the period from 1956 to 2010s, the glacier area in glaciated regions along the Silk Road Economic Belt decreased by 4547.43 km² with a percentage change of -20.88%. In the past 50 years, 3114 glaciers have disappeared, 1318 glaciers have been separated into 2964, and 73 glaciers have been merged into 35, and the loss of glacial ice volume was about 419.35 km³. (4) The glacier changes along the Silk Road Economic Belt had the generally accelerated trend from west to east and accordingly the rate of reduction appeared from southwest to northeast. The number of glaciers that disappeared in the north was greater than that in the south. The area of the northeast was reduced most, and the largest reduction rate was found in the southeast. (5) During the period from 1961 to 2010, a warming and humidification trend was observed in the glaciated regions along the Silk Road Economic Belt, the increase rate of temperature in the dry season was greater than that in the wet season, and the increase in the precipitation in the dry season was smaller than that in the wet season. The pattern of climate combination was not conducive to the accumulation of glaciers, hence leading to the retreating of glaciers. The scale of glacier development also had some impact on the retreat of glaciers, but there were spatial differences in terms of the driving forces of glaciers in each mountain range.