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冰架崩解是南极洲物质损耗的主要途径,崩解是应力作用引起的裂隙(或裂缝)传播的结果,裂隙位置和深度的探测是理解崩解机理过程的重要基础.本文提出了一种利用卫星激光测高ICESat-1/GLAS高程数据产品提取冰架表面冰裂隙的方法,并以南极洲埃默里冰架为例验证了这种方法探测裂隙位置的准确性和深度探测精度.同时,基于提取的裂隙点深度分布特征提出了裂隙峰值应力点的探测方法,可用于追踪冰裂隙初始裂口位置和探测导致冰架崩解的高危区.利用2003～2008年间16个运行时期内132条ICESat-1/GLAS高程轨迹线分析了埃默里冰架冰裂隙深度的时空分布和裂隙峰值应力点的空间分布.结果显示,探测到的裂隙点深度在2.0～31.7 m均在海平面以上;裂隙深度变化未显示出随时间推移和冰流移动而增加的趋势,说明平流移动到冰架前缘的裂隙基本不会直接导致冰架的崩解;冰架局部应力集中区主要分布在冰流的缝合区内.
The disintegration of ice shelves is the main way of material loss in Antarctica, disintegration is the result of the propagation of cracks (or cracks) caused by the stress, and the detection of crack location and depth is an important basis for understanding the disintegration mechanism. Satellite laser altimeter ICESat-1 / GLAS elevation data extraction ice shelves surface ice fissure method and an example of the Emery Ice Shelf in Antarctica to verify the accuracy of this method to detect fracture location and depth of detection accuracy.At the same time, based on This paper proposes a method to detect the peak stress point of fractures, which can be used to track the location of the initial rips and detect the high-risk areas that cause the ice shelves to disintegrate. Using 132 ICESat- 1 / GLAS elevation trajectories were used to analyze the spatio-temporal distribution of ice crack depth and the spatial distribution of crest stress points in the Emery Ice Shelf. The results show that the depths of the detected fractures are above sea level from 2.0 to 31.7 m; The changes do not show an increase over time and along the ice flow, indicating that the fissures moving advancing to the front of the ice shelf do not generally cause the ice shelf to disintegrate directly; ice Local stress concentration region is mainly distributed in the ice flow zone suture.