Knowing where crevasses are is critical for planning safe on-ice field operations. Previous methods have ranged from real-time imaging of subsurface structures using ground penetrating radar, to mapping of crevasses over large areas using satellite imagery, with each method having it's own strengths and weaknesses. In this paper we compare the detection of crevasses at the Totten Glacier, East Antarctica, from helicopter-borne ground penetrating radar with satellite-based microwave synthetic aperture radar imagery. Our results show that the 80 MHz helicopter-borne ground penetrating radar was able to detect crevasses up to a depth of 70 m, with snow bridge thickness of >30 m. Comparison with TerraSAR-X (X-band, 9.6 GHz) satellite imagery indicates that the latter is highly effective, detecting 100% of crevasses with snow bridges of up to 4 m thick and detected 95% of crevasses with snow bridges up to 10 m thick. The ability of both methods to identify individual crevasses is affected by several factors including crevasse geometry, survey or satellite orientation and snow moisture content, and further experiments are planned to investigate performance under a wider range of conditions.

中文翻译：

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比较卫星和直升机观测裂缝的方法，在东南极洲的应用

了解裂缝的位置对于规划安全的冰上野外作业至关重要。以前的方法范围从使用探地雷达实时成像地下结构，到使用卫星图像绘制大面积裂缝，每种方法都有自己的优点和缺点。在本文中，我们比较了从直升机机载探地雷达和基于卫星的微波合成孔径雷达图像对南极东部托滕冰川裂缝的检测。我们的结果表明，80 MHz 直升机机载探地雷达能够探测到深度达 70 m、雪桥厚度 >30 m 的裂缝。与 TerraSAR-X（X 波段，9.6 GHz）卫星图像的比较表明后者非常有效，检测到 100% 具有高达 4 m 厚的雪桥的裂缝和检测到 95% 具有高达 10 m 厚的雪桥的裂缝。这两种方法识别单个裂缝的能力受到若干因素的影响，包括裂缝几何形状、测量或卫星方向以及雪的含水量，并且计划进行进一步的实验以研究更广泛条件下的性能。