ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-30-929-2012 Electron radiation belt data assimilation with an ensemble Kalman filter relying on the Salammbô code Bourdarie S. A. 1 Maget V. F. 1 ONERA the French Aerospace lab, Toulouse, France 08 06 2012 30 6 929 943 Copyright: © 2012 S. A. Bourdarie 2012 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/30/929/2012/angeo-30-929-2012.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/30/929/2012/angeo-30-929-2012.pdf

In this study we implement a data assimilation tool using a 3-D radiation belt model and an ensemble Kalman filter approach. High time and space reanalysis of the electron radiation belt fluxes is obtained over the time period 5 October to 25 October 1990 by combining sparse observations with the Salammbô 3-D model in an optimal way. The convergence of the ensemble Kalman filter is analyzed carefully. The risk of using a biased physical model is discussed and relative consequences are highlighted. Finally, a validation against CRRES data and major improvements compared to pure physics based model are presented.

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