Methods for inferring regional surface‐mass anomalies from Gravity Recovery and Climate Experiment (GRACE) measurements of time‐variable gravity
Methods for inferring regional surface‐mass anomalies from Gravity Recovery and Climate Experiment (GRACE) measurements of time‐variable gravity
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DOI：
10.1029/2001jb000576
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发表时间：
2002-09
影响因子：
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通讯作者：
S. Swenson;J. Wahr
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文献类型：
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作者：
S. Swenson;J. Wahr
重力恢复和气候实验（GRACE）将提供描述地球重力场的球谐系数的月平均值，我们期望从中推断质量随时间变化的变化，在长度尺度为几百公里或更大的任意区域平均，精度优于等效水厚度1厘米。这些数据将有助于研究海洋中的水分布、极地冰盖上的雪和冰以及大陆的水和雪储存的变化。我们描述了从GRACE重力系数提取区域质量异常的方法。创建空间平均核是为了隔离单个区域的重力信号，同时最大限度地减少GRACE观测误差和周围冰川、水文和海洋重力信号污染的影响。然后，我们估计了任意形状和大小区域的平均核的可能精度。
[1] The Gravity Recovery and Climate Experiment, GRACE, will deliver monthly averages of the spherical harmonic coefficients describing the Earth's gravity field, from which we expect to infer time-variable changes in mass, averaged over arbitrary regions having length scales of a few hundred kilometers and larger, to accuracies of better than 1 cm of equivalent water thickness. These data will be useful for examining changes in the distribution of water in the ocean, in snow and ice on polar ice sheets, and in continental water and snow storage. We describe methods of extracting regional mass anomalies from GRACE gravity coefficients. Spatial averaging kernels were created to isolate the gravity signal of individual regions while simultaneously minimizing the effects of GRACE observational errors and contamination from surrounding glacial, hydrological, and oceanic gravity signals. We then estimated the probable accuracy of averaging kernels for regions of arbitrary shape and size.