Background error covariance functions for Doppler radial‐wind analysis
Background error covariance functions for Doppler radial‐wind analysis
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DOI：
10.1256/qj.02.129
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发表时间：
2003-04
影响因子：
8.9
通讯作者：
Qin Xu;J. Gong
中科院分区：
文献类型：
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作者：
Qin Xu;J. Gong
Under the assumption that the vector field of the background wind error is Gaussian random, homogeneous and isotropic in the horizontal, a two‐dimensional form of error covariance function is derived for the radial component of the background wind projected onto the direction of radar beam at a low elevation. The derived covariance function is homogeneous but non‐isotropic in the horizontal, and approximately homogeneous on the conical surface of low‐elevation radar scans. This covariance function can be applied directly to statistical interpolation of radar‐observed radial winds on the conical surface, although the true optimality of the analysis depends on the underlying assumption. It can also be used as an influence function for the radial‐wind analysis with zero background. The structure of this covariance function is interpreted in terms of the influence of a single point observation on the radial‐wind analysis. The utility and merits of this covariance function are demonstrated by numerical experiments. Copyright © 2003 Royal Meteorological Society
