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Data assimilation with the EnKF in a 1-D numerical model of a North Sea station

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Ponsar, Stephanie [UCL] Luyten, Patrick [UCL]

A series of numerical experiments for data assimilation with the Ensemble Kalman Filter (EnKF) in a shallow water model are reported. Temperature profiles measured at a North Sea location, 55A degrees 30ES North and 0A degrees 55ES East (referred to as the CS station of the NERC North Sea project), are assimilated in 1-D simulations. Comparison of simulations without assimilation to model results obtained when assimilating data with the EnKF allows us to assess the filter performance in reproducing features of the observations not accounted for by the model. The quality of the model error sampling is tested as well as the validity of the Gaussian hypothesis underlying the analysis scheme of the EnKF. The influence of the model error parameters and the frequency of the data assimilation are investigated and discussed. From these experiments, a set of optimal parameters for the model error sampling are deduced and used to test the behavior of the EnKF when propagating surface information into the water column.

Document type Communication à un colloque (Conference Paper) – Présentation orale avec comité de sélection
Access type Accès restreint
Publication date 2009
Language Anglais
Conference "14th International Biennial Conference of the Joint-Numerical-Sea-Modelling-Group", Univ Bergen, Bergen(Norway) (Jun 23-25, 2008)
Journal information "Ocean Dynamics : theoretical, computational oceanography and monitoring" - Vol. 59, no. 6, p. 983-996 (2009)
Peer reviewed yes
issn 1616-7341
e-issn 1616-7228
Publisher Springer Heidelberg (Heidelberg)
Affiliation UCL - Autre
Keywords Data Assimilation ; Ensemble Kalman Filter ; Numerical Modelling ; North Sea
Links
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Bibliographic reference Ponsar, Stephanie ; Luyten, Patrick. Data assimilation with the EnKF in a 1-D numerical model of a North Sea station.14th International Biennial Conference of the Joint-Numerical-Sea-Modelling-Group (Univ Bergen, Bergen(Norway), Jun 23-25, 2008). In: Ocean Dynamics : theoretical, computational oceanography and monitoring, Vol. 59, no. 6, p. 983-996 (2009)
Permanent URL http://hdl.handle.net/2078.1/58846