Ocean Science www.ocean-sci.net 1812-0784 1812-0792 2 2 2006 10.5194/os-2-223-2006 http://www.ocean-sci.net/2/223/2006/ http://www.ocean-sci.net/2/223/2006/os-2-223-2006.html http://www.ocean-sci.net/2/223/2006/os-2-223-2006.pdf 223 236 2006-11-22 Implementation of position assimilation for ARGO floats in a realistic Mediterranean Sea OPA model and twin experiment testing V. Taillandier vincent@sp.ismar.cnr.it A. Griffa CNR-ISMAR, La Spezia, Italy RSMAS, University of Miami, Florida, USA In this paper, a Lagrangian assimilation method is presented and implemented in a realistic OPA OGCM with the goal of providing an assessment of the assimilation of realistic Argo float position data. We focus on an application in the Mediterranean Sea, where in the framework of the MFSTEP project an array of Argo floats have been deployed with parking depth at 350 m and sampling interval of 5 days. 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