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Ocean Dynamics

, Volume 65, Issue 1, pp 49–63 | Cite as

Optimized boundary conditions at staircase-shaped coastlines

  • Eugene KazantsevEmail author
Article

Abstract

A 4D-Var data assimilation technique is applied to a rectangular-box configuration of the NEMO in order to analyze the optimal parametrization of boundary conditions at lateral boundaries. The impact of staircase-shaped coastlines is studied by rotating the model grid around the center of the box. Rotations on 30 and 45 are studied with single and double gyre forcing patterns. It is shown that optimized boundary conditions compensate the errors induced by the staircase-like approximation of the coastline.

Keywords

Variational data assimilation Boundary conditions NEMO model 

Notes

Acknowledgments

The author would like to express his gratitude to Julien Le Sommer for helpful discussions on the physical background of the model and to two anonymous reviewers for valuable comments and constructive suggestions on the manuscript.

This work was supported by the French National Programme LEFE/INSU-GMMC. All the contour pictures have been prepared by the Grid Analysis and Display System (GrADS) developed in the Centre for Ocean-Land-Atmosphere Interactions, Department of Meteorology, University of Maryland.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.INRIA, Projet MOISE, Laboratoire Jean KuntzmannGrenoble Cedex 9France

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