Improving InSAR elevation models in Antarctica using laser altimetry, accounting for ice motion, orbital errors and atmospheric delays
Improving InSAR elevation models in Antarctica using laser altimetry, accounting for ice motion, orbital errors and atmospheric delays
复制标题
使用激光测高改进南极洲的 InSAR 高程模型，考虑冰运动、轨道误差和大气延迟
DOI：
10.1016/j.rse.2015.01.017
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发表时间：
2015
影响因子：
13.5
通讯作者：
Wen Yangmao
中科院分区：
文献类型：
--
作者：
Zhou Yu;Zhou Chunxia;Deng Fanghui;E Dongchen;Liu Haiyan;Wen Yangmao
冰动力学与气候变化密切相关。然而，缺乏足够的水平分辨率和垂直精度的数字高程模型（DEM）多年来一直是动态研究的主要问题。现有的南极DEM来自卫星雷达和激光测高以及有限的地面数据;这些稀疏的数据集导致空间分辨率很差（几百米到1公里）。在本文中，我们提出了一种方法，用于生成高精度和高分辨率DEM使用干涉合成孔径雷达（干涉合成孔径雷达）和冰，云和陆地高程卫星（ICESat）激光测高减少冰运动，卫星轨道误差和地形相关的大气延迟的影响。在格罗夫山脉地区的案例研究表明，干涉合成孔径雷达DEM的均方根（RMS）误差为5.9 m，优于雷达卫星南极测绘项目（RAMP）（21.1 m）和班伯（Bamber）（8.5 m）DEM。新的DEM被用来计算冰速度超过格罗夫山脉地区的GPS测量已收集比较。与美国航天局的“制作用于研究环境的地球系统数据记录”（MEaSUREs）的“基于InSAR的南极洲冰速图”相比，根据长基线干涉图和新的数字高程模型估算的冰速具有较小的RMS误差;这表明，有了新的数字高程模型，基线长度不再是基于InSAR的冰速制图准确性的限制因素。
Ice dynamics is closely related to climate change. However, a lack of digital elevation models (DEMs) of sufficient horizontal resolution and vertical precision has been a major issue in dynamic studies for years. Existing Antarctic DEMs are derived from satellite radar and laser altimetry as well as limited terrestrial data; these sparse datasets result in poor spatial resolution (hundreds of metres to 1 km). In this paper, we propose a method for generating high-accuracy and high-resolution DEMs using interferometric synthetic aperture radar (InSAR) and Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry by reducing the influence of ice motion, satellite orbital errors and topographically correlated atmospheric delays. A case study in the Grove Mountains area shows that the InSAR DEM has a root-mean-square (RMS) error of 5.9 m, which is better than the Radarsat Antarctic Mapping Project (RAMP) (21.1 m) and Bamber (8.5 m) DEMs. The new DEM is used to calculate ice velocity over the Grove Mountains area where GPS measurements have been collected for comparison. Compared to the NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) InSAR-Based Antarctica Ice Velocity Map, ice velocity estimates from long-baseline interferogram and the new DEM have a smaller RMS error; this suggests that with the new DEM, baseline length is no longer a limiting factor for the accuracy of InSAR-based ice velocity mapping.