2000—2015年格拉丹东冰川面积变化与物质平衡遥感监测

Remote Sensing Monitoring of Glacier Change and Mass Balance(2000-2015)in Geladandong

为评估格拉丹东冰川在全球气候变暖背景下的变化,利用Landsat遥感影像、SRTM1、TanDEM-X资料,基于大地测量法对格拉丹东地区2000—2015年的冰川面积变化和物质平衡进行了探讨.结果表明:①2000—2015年格拉丹东地区冰川总面积从(842.46±2.1)km^(2),减少到(819.82±1.6)km^(2),面积缩小(26.6±2.6)km^(2),占冰川总面积的3.20%±0.3%,年均缩小率为0.2%±0.02%.②2000—2015年格拉丹东地区冰川平均减薄(-2.72±0.21)m,年均变化为(-0.17±0.04)m·a^(-1).冰川体积减少(2.29±0.17)km^(3),年均物质平衡为(-0.13±0.01)mw.e·a^(-1),累计物质亏损量为(-2.08±0.15)mw.e.,换算成水当量约为(108.2±37.9)×10^(4) m^(3),格拉丹东地区冰川物质平衡总体呈现负平衡状态,但其中有4条冰川表现出正物质平衡状态.③2000—2015年格拉丹东冰川总体面积一直减少,冰川物质平衡处于负状态,气温升高可能是导致格拉丹东地区冰川不断退缩的主要原因.④格拉丹东地区前进与跃动冰川是热控和水控机制共同促成的,内部液态水的增加导致其对冰川的润滑作用也增大,促使冰川上游物质不断向下游转移,从而导致冰川前进与跃动.

In order to further understand the glacier change in Geladandong under the background of climate change,Glacier area changes and mass balance between 2000 and 2015 in Geladandong were determined by using geodetic methods based on Landsat TM,SRTM1 and TanDEM-X data.Results show that from 2000 to 2015,the area of the glacier in Geladandong decreased from(842.46±2.1)km^(2) to(819.82±1.6)km^(2),accounting for 3.20%±0.3%of the area of the glacier,with an average annual shrinking rate of 0.2%±0.02%.The average glacier thinning in Geladandong region was(-2.72±0.21)m,with an average annual change of(-0.17±0.04)m·a^(-1).The glacier volume decreased(2.29±0.17)km^(3),the annual average mass balance was(-0.13±0.01)mw.e·a^(-1),and the cumulative mass loss was(-2.08±0.15)mw.e.,which was about(108.2±37.9)×10^(4) m^(3) in water equivalent.The glacial material balance in Geladandong region presents negative balance on the whole,but four glaciers show positive mass balance.During 2000-2015,the overall area of Geladandong glacier has been decreasing,and the balance of glacier material is in a negative state.The rising temperature may be the main reason for the continuous shrinking of Geladandong glacier.The advancing and leaping glacier in Geladandong region is facilitated by the mechanism of heat control and water control,the increase of internal liquid water leads to its lubricating effect on the glacier is also increased,and causes the upstream material of the glacier to transfer to the downstream,thus leading to the advancing and leaping of the glacier.