High resolution (400 m) motion characterization of sea ice using ERS-1 SAR imagery
High resolution (400 m) motion characterization of sea ice using ERS-1 SAR imagery
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DOI：
10.1016/j.coldregions.2007.06.006
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发表时间：
2008-04
影响因子：
4.1
通讯作者：
M. Thomas;C. Geiger;C. Kambhamettu
中科院分区：
文献类型：
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作者：
M. Thomas;C. Geiger;C. Kambhamettu
利用ERS-1卫星合成孔径雷达（SAR）图像，采用多分辨率处理系统对海冰运动场进行高分辨率绘制。结果是以400米分辨率提供的，这比标准合成孔径雷达运动产品（5-10公里）大一个数量级。一个误差传播实验表明，对于位置不确定性和处理技术造成的不变切变中的噪声，标准偏差为1.3% day-1。当识别剪切带不连续性时，我们使用此噪声水平来确定显著较低的阈值。作为例子，一个24天的图像序列处理使用该系统来检查剪切带的发展和演变。这种演变是由于海洋环流和风迫使沿着大陆架断裂所造成的地形转向。此外，我们适应线积分卷积（LIC）来描绘存在于运动场的流动模式。总的来说，这些运动产品提供了有价值的描述的非刚性动力学发生在海冰。我们的目标是补充现有的雷达卫星地球物理处理系统（RGPS）运动产品，并帮助验证和进一步发展目前最先进的“铅解决”海冰模型。这种形式的海冰可视化是重要的了解空气-冰-海动量传递过程，通过小规模到大规模的断裂事件与船舶航行的应用。
Using Synthetic Aperture Radar (SAR) images from ERS-1, we render high resolution motion fields of sea ice using a multi-resolution processing system. The results are provided at a 400 m resolution, which is an order of magnitude greater than the standard SAR motion products (5–10 km). An error propagation experiment shows a standard deviation of 1.3% day−1for the noise in invariant shear resulting from position uncertainties and processing techniques. We use this noise level to determine a significant lower threshold when identifying shear zone discontinuities. As example, a 24-day sequence of images is processed using this system to examine the development and evolution of a shear zone. This evolution is in response to the topographic steering caused by ocean circulation and wind forcing along a continental shelf break. In addition, we adapt the Line Integral Convolution (LIC) to depict flow patterns present in the motion field. Collectively, these motion products provide valuable descriptions of the non-rigid dynamics taking place within the sea ice. Our goal is to complement the existing RADARSAT Geophysical Processing System (RGPS) motion products and aid in the validation and further development of the most progressive “lead-resolving” sea ice models currently available. This form of sea ice visualization is important for understanding air–ice–sea momentum transfer processes that transcend through small-scale to large-scale fracture events with application to ship navigation.