Variable penetration depth of interferometric synthetic aperture radar signals on Alaska glaciers: a cold surface layer hypothesis
Variable penetration depth of interferometric synthetic aperture radar signals on Alaska glaciers: a cold surface layer hypothesis
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阿拉斯加冰川干涉合成孔径雷达信号的可变穿透深度：冷表层假设
DOI：
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发表时间：
2013
影响因子：
2.9
通讯作者：
Joanna C. Young
中科院分区：
文献类型：
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作者：
A. Gusmeroli;A. Arendt;D. Atwood;B. Kampes;M. Sanford;Joanna C. Young
摘要美国阿拉斯加山脉最大的冰川Kahiltna冰川5 m分辨率的P波段干涉合成孔径雷达（干涉合成孔径雷达）数据显示，穿透深度δP具有明显的空间变化。我们通过对X-和P-波段数字高程模型进行差分来获得δP。δP在冰川上变化很大，但可以区分出代表性的区域。在堆积区，δP随海拔的降低而降低，从渗滤带的18 ± 3 m降低到湿雪带的10 ± 4 m。在消融区的中心部分，没有碎片和裂缝的位置，我们确定了一个非常高的δP（34 ± 4 m）的区域，该区域在较低的海拔（裸冰为23 ± 3 m，碎片覆盖的冰为5- 10 m）处降低。我们观察到，δP的空间配置是一致的，每个带的预期的热状况：δP是高的冷的积雪/冰可能发生的区域（即渗透区和消融区上部）和低的温带表面积雪/冰可能存在的区域（湿雪区和消融区下部）。我们认为，在烧蚀区上部观察到的非常高的δP是由于冷表面层的存在。
Abstract P-band interferometric synthetic aperture radar (InSAR) data at 5 m resolution from Kahiltna Glacier, the largest glacier in the Alaska Range, Alaska, USA, show pronounced spatial variation in penetration depth, δP. We obtained δP by differencing X- and P-band digital elevation models. δP varied significantly over the glacier, but it was possible to distinguish representative zones. In the accumulation area, δP decreased with decreasing elevation from 18 ± 3 m in the percolation zone to 10 ± 4 m in the wet snow zone. In the central portion of the ablation area, a location free of debris and crevasses, we identified a zone of very high δP (34 ± 4 m) which decreased at lower elevations (23 ± 3 m in bare ice and 5-10m in debris-covered ice). We observe that the spatial configuration of δP is consistent with the expected thermal regime of each zone: δP is high in areas where cold firn/ice likely occurs (i.e. percolation zone and upper ablation area) and low in areas where temperate surface firn/ice likely exists (wet snow zone and lower ablation area). We suggest that the very high δP observed in the upper ablation area is due to the presence of a cold surface layer.