Parallelization in the time dimension of four‐dimensional variational data assimilation
Tóm tắt
The current evolution of computer architectures towards increasing parallelism requires a corresponding evolution towards more parallel data assimilation algorithms. In this article, we consider parallelization of weak‐constraint four‐dimensional variational data assimilation (4D‐Var) in the time dimension. We categorize algorithms according to whether or not they admit such parallelization and introduce a new, highly parallel weak‐constraint 4D‐Var algorithm based on a saddle‐point representation of the underlying optimization problem. The potential benefits of the new saddle‐point formulation are illustrated with a simple two‐level quasi‐geostrophic model.
Từ khóa
Tài liệu tham khảo
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