Articles | Volume 28, issue 1
https://doi.org/10.5194/npg-28-93-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/npg-28-93-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Feb 2021
Research article |
| 08 Feb 2021
| 08 Feb 2021
Behavior of the iterative ensemble-based variational method in nonlinear problems
Department of Statistical Modeling, The Institute of Statistical Mathematics, Tachikawa, Japan
Center for Data Assimilation Research and Applications,
Joint Support Center for Data Science Research, Tachikawa, Japan
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Short summary
The ensemble-based variational method is a method for solving nonlinear data assimilation problems by using an ensemble of multiple simulation results. Although this method is derived based on a linear approximation, highly uncertain problems, in which system nonlinearity is significant, can also be solved by applying this method iteratively. This paper reformulated this iterative algorithm to analyze its behavior in high-dimensional nonlinear problems and discuss the convergence.
The ensemble-based variational method is a method for solving nonlinear data assimilation...
