Ocean Science www.ocean-sci.net 1812-0784 1812-0792 4 3 2008 10.5194/os-4-199-2008 http://www.ocean-sci.net/4/199/2008/ http://www.ocean-sci.net/4/199/2008/os-4-199-2008.html http://www.ocean-sci.net/4/199/2008/os-4-199-2008.pdf 199 213 2008-09-01 Influence of Rossby waves on primary production from a coupled physical-biogeochemical model in the North Atlantic Ocean G. Charria guillaume.charria@legos.obs-mip.fr I. Dadou P. Cipollini M. Drévillon V. Garçon Laboratoire d'Etudes en Géophysique et Océanographie Spatiales, UMR5566/CNRS, Toulouse, France National Oceanography Centre, Southampton, United Kingdom CERFACS, MERCATOR-Océan, Toulouse, France Rossby waves appear to have a clear signature on surface chlorophyll concentrations which can be explained by a combination of vertical and horizontal mechanisms. In this study, we investigate the role of the different physical processes in the north Atlantic to explain the surface chlorophyll signatures and the consequences on primary production, using a 3-D coupled physical/biogeochemical model for the year 1998. <br><br> The analysis at 20 given latitudes, mainly located in the subtropical gyre, where Rossby waves are strongly correlated with a surface chlorophyll signature, shows the important contribution of horizontal advection and of vertical advection and diffusion of inorganic dissolved nitrogen. The main control mechanism differs according to the biogeochemical background conditions of the area. <br><br> The surface chlorophyll anomalies, induced by these physical mechanisms, have an impact on primary production. 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