Incorporating Ensemble Covariance in the Gridpoint Statistical Interpolation Variational Minimization: A Mathematical Framework

• DOI: 10.1175/2010mwr3245.1
• Publication Date: 2010-03-09T16:00:30Z
• Authors: Xuguang Wang
• Keywords: Interpolation; Minification

Abstract Gridpoint statistical interpolation (GSI), a three-dimensional variational data assimilation method (3DVAR) has been widely used in operations and research numerical weather prediction. The operational GSI uses static background error covariance, which does not reflect the flow-dependent statistics. Incorporating ensemble covariance provides natural way to estimate manner. Different from other 3DVAR-based hybrid systems that are preconditioned on square root of commonly minimization is upon full matrix. A mathematical derivation therefore provided demonstrate how incorporate minimization.