Surface crevasses covered by snow bridges can be mapped remotely on ice sheets and glaciers using active microwave synthetic aperture radar. They are highlighted against the surrounding snow due to increased scattering from the side-walls and base of snow bridges and usually appear as linear features. The contrast between crevasses and crevasse-free regions depends on the design of the sensor, the image acquisition parameters and the properties of the snow. Here we quantify how crevassed regions are represented at X-band for different polarizations, look directions and incidence angles, and discuss whether additional information about their physical properties can be gained from their radar signature. Snow bridge thicknesses and crevasse widths are measured on the ground in the McMurdo Shear Zone and Brunt Ice Shelf by ground-penetrating radar and excavation. TerraSAR-X is shown to reliably distinguish crevasse location, balancing penetration into the snow and horizontal resolution. We provide recommendations for radar imaging parameters that optimize the identification of individual crevasses and crevassed regions.

可以使用有源微波合成孔径雷达将被雪桥覆盖的地表裂缝远程绘制在冰盖和冰川上。由于从雪桥的侧壁和底部的散射增加，它们在周围的雪上突出显示，并且通常显示为线性特征。裂隙和无裂隙区域之间的对比度取决于传感器的设计，图像采集参数和积雪的性质。在这里，我们量化了如何在X波段上针对不同的极化，观察方向和入射角表示裂隙区域，并讨论是否可以从其雷达特征中获得有关其物理特性的其他信息。雪道厚度和裂隙宽度是通过探地雷达和挖掘在麦克默多剪力区和布伦特冰架的地面上测量的。已显示TerraSAR-X能够可靠地区分缝隙位置，平衡对雪的穿透力和水平分辨率。我们为雷达成像参数提供建议，以优化单个裂缝和裂缝区域的识别。