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全球气候变暖严重影响冰川的稳定性，南极多条冰川表面发生塌陷。由于缺少高空间和高时间分辨率的南极地表高程模型（Digital Elevation Model，DEM），目前单支冰川表面时空变化的研究不充分。利用2011至2016年间11期南极参考高程模型（The Reference Elevation Model of Antarctica, REMA）数据，开展东南极达尔克冰川表面塌陷区域的高程变化监测，并利用Landsat 7、8和Worldview-2光学影像等数据分析塌陷过程和原因。结果表明，达尔克冰川在2013年发生了一起严重的塌陷事件，塌陷深度最大约45.29 m，造成了约26.29×10^6 m^3的水体损失；塌陷发生后，该区表面高程不断增加，于2016年恢复至塌陷前的高程。塌陷区具有明显的整体性沉降特征，并存在融水聚集，推测塌陷和达尔克冰川冰下湖的排水过程存在密切的联系。本研究证明达尔克冰川存在较大的不稳定性，同时验证了REMA数据监测冰川表面塌陷的可行性，为未来精细化监测南极冰盖/冰架响应气候变化提供技术参考。
With global warming, glacier surface depressions are frequently occurring in Antarctica, which is challenging for stability evaluation of glaciers. However, the shortage of high spatial and temporal resolution digital elevation model, researches on single glacier surface variations remain rather limited. 11-period REMA during 2011-2016 were used to measure surface sudden depression on Dalk Glaicer, East Antarctica. Landsat 7, 8 Wordlview-2 satellite images and so on were utilized to analyze the process and reason of the glacier surface evolution. The results show that: a serious surface depression occurred on Dalk Glacier in 2013 with maximum depression depth of 45.29 m and caused the englacially stored meltwater loss of 26.29×10^6 m^3; then the elevation were increasing until that the elevation achieved the pre-depression level in 2016.The depression was typical of uniform settlement and intense surface melting. And the depression was closely interconnected with active ice-covered lakes drainage inside Dalk Glacier. Thus, Dalk glacier has been in a dangerous and unstable position due to melting and depressions. In addition, REMA was verified to monitor glacier surface depression, which was valuable for refine monitoring ice shelf and glacier response to climate change.