Faculty of Geography, M.V.Lomonosov Moscow State University, Moscow, Russia.
ETC "ScanEX", Moscow, Russia.
Sci Total Environ. 2016 Aug 15;562:364-378. doi: 10.1016/j.scitotenv.2016.03.162. Epub 2016 Apr 19.
The observed increase in summer temperatures and the related glacier downwasting has led to a noticeable decrease of frozen water resources in Central Asia, with possible future impacts on the economy of all downstream countries in the region. Glaciers in the Ak-Shyirak massif, located in the Inner Tien Shan, are not only affected by climate change, but also impacted by the open pit gold mining of the Kumtor Gold Company. In this study, glacier inventories referring to the years 2003 and 2013 were created for the Ak-Shyirak massif based on satellite imagery. The 193 glaciers had a total area of 351.2±5.6km(2) in 2013. Compared to 2003, the total glacier area decreased by 5.9±3.4%. During 2003-2013, the shrinkage rate of Ak-Shyirak glaciers was twice than that in 1977-2003 and similar to shrinkage rates in Tien Shan frontier ranges. We assessed glacier volume in 2013 using volume-area (VA) scaling and GlabTop modelling approaches. Resulting values for the whole massif differ strongly, the VA scaling derived volume is 30.0-26.4km(3) whereas the GlabTop derived volume accounts for 18.8-13.2km(3). Ice losses obtained from both approaches were compared to geodetically-derived volume change. VA scaling underestimates ice losses between 1943 and 2003 whereas GlabTop reveals a good match for eight glaciers for the period 2003-2012. In comparison to radio-echo soundings from three glaciers, the GlabTop model reveals a systematic underestimation of glacier thickness with a mean deviation of 16%. GlabTop tends to significantly underestimate ice thickness in accumulation areas, but tends to overestimate ice thickness in the lowermost parts of glacier snouts. Direct technogenic impact is responsible for about 7% of area and 5% of mass loss for glaciers in the Ak-Shyirak massif during 2003-2013. Therefore the increase of summer temperature seems to be the main driver of accelerated glacier shrinkage in the area.
观测到的夏季气温上升以及相关的冰川消融，导致中亚地区的冻结水资源明显减少，这可能对该地区所有下游国家的经济产生未来影响。天山内部的阿克什亚雷克山脉的冰川不仅受到气候变化的影响，还受到库姆托尔金矿露天开采的影响。在这项研究中，根据卫星图像，为阿克什亚雷克山脉创建了 2003 年和 2013 年的冰川清单。193 条冰川总面积为 351.2±5.6km(2)在 2013 年。与 2003 年相比，总冰川面积减少了 5.9±3.4%。在 2003-2013 年间，阿克什亚雷克冰川的退缩速度是 1977-2003 年的两倍，与天山前缘山脉的退缩速度相似。我们使用体积-面积 (VA) 缩放和 GlabTop 建模方法评估了 2013 年的冰川体积。整个山脉的结果值差异很大，VA 缩放得到的体积为 30.0-26.4km(3)，而 GlabTop 得到的体积为 18.8-13.2km(3)。从两种方法获得的冰损失与大地测量得出的体积变化进行了比较。VA 缩放方法在 1943 年至 2003 年期间低估了冰损失，而 GlabTop 方法在 2003-2012 年期间对于 8 条冰川的结果与实测值吻合较好。与三条冰川的无线电回声测深结果相比，GlabTop 模型显示冰川厚度存在系统低估，平均偏差为 16%。GlabTop 倾向于在积累区显著低估冰厚度，但在冰川末端的较低部分倾向于高估冰厚度。在 2003-2013 年间，阿克什亚雷克山脉的冰川直接受到人为影响的面积约占 7%，质量损失约占 5%。因此，夏季气温升高似乎是该地区冰川加速退缩的主要驱动因素。
