Ocean Science www.ocean-sci.net 1812-0784 1812-0792 2 2 2006 10.5194/os-2-173-2006 http://www.ocean-sci.net/2/173/2006/ http://www.ocean-sci.net/2/173/2006/os-2-173-2006.html http://www.ocean-sci.net/2/173/2006/os-2-173-2006.pdf 173 181 2006-10-17 Analysis of the circulation and shelf-slope exchanges in the continental margin of the northwestern Mediterranean A. Jordi vieaajb@uib.es G. Basterretxea A. Orfila J. Tintoré IMEDEA (CSIC-UIB), Institut Mediterrani d'Estudis Avançats, Esporles, Illes Balears, Spain In this paper, we present the results from a high horizontal resolution numerical simulation of the northwestern Mediterranean using a z-level, non-hydrostatic, primitive equation ocean model (DieCAST). The high resolution allows an accurate representation of the submarine canyons that presides in the region. The model is one-way coupled to a large scale model of the Mediterranean Sea through open boundaries and uses the atmospheric forcing fields provided in terms of HIRLAM outputs by the Spanish National Institute of Meteorology. Results show that the model can successfully reproduce the complex general circulation characteristics of the area, including the modifications induced by canyons in their vicinity and other phenomena observed such as instabilities and coastal trapped waves. The sea surface temperature is similar to satellite observations except that simulated temperatures are slightly warmer near the coast than observations and colder near the open boundaries. An important topic of this work is the computation of the shelf-slope exchanges, which are able to renew shelf waters in a few months. Álvarez, A., Tintoré, J., and Sabatés, A.: Flow modification of shelf-slope exchange induced by a submarine canyon off the northeast Spanish coast, J. Geophys. 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