Inhomogeneous Background Error Modeling and Estimation over Antarctica
Inhomogeneous Background Error Modeling and Estimation over Antarctica
复制标题
南极洲非均匀背景误差建模与估计
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
T. Auligne
中科院分区：
文献类型：
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作者：
Y. Michel;T. Auligne
变分同化方案中分析增量的结构很大程度上受背景误差协方差矩阵公式的驱动，特别是在数据稀疏的地区，如南极地区。本研究中的网格点背景误差建模利用基于回归的变量间平衡算子、经验正交函数分解来定义垂直相关性、网格点方差和高阶高效递归滤波器来施加水平相关性。一个特殊之处在于回归算子和递归滤波器在空间上是非齐次的。利用天气研究与预报（WRF）模式，根据一组预报差值计算背景误差统计量。感兴趣的中尺度有限区域覆盖南极洲。背景误差的不均匀性与该地区特殊的地形和物理有关。差异似乎特别明显……
Abstract The structure of the analysis increments in a variational data assimilation scheme is strongly driven by the formulation of the background error covariance matrix, especially in data-sparse areas such as the Antarctic region. The gridpoint background error modeling in this study makes use of regression-based balance operators between variables, empirical orthogonal function decomposition to define the vertical correlations, gridpoint variances, and high-order efficient recursive filters to impose horizontal correlations. A particularity is that the regression operators and the recursive filters have been made spatially inhomogeneous. The computation of the background error statistics is performed with the Weather Research and Forecast (WRF) model from a set of forecast differences. The mesoscale limited-area domains of interest cover Antarctica. Inhomogeneities of background errors are shown to be related to the particular orography and physics of the area. Differences seem particularly pronounce...