OS Ocean Science OS Ocean Sci. 1812-0792 Copernicus Publications Göttingen, Germany 10.5194/os-3-345-2007 Assessment of the importance of the current-wave coupling in the shelf ocean forecasts Jordà G. 1 2 Bolaños R. 2 Espino M. 2 Sánchez-Arcilla A. 2 Institut Mediterrani d'Estudis Avançats (IMEDEA), c./Miquel Marqués 21, 07190 Esporles, Illes Balears, Spain Laboratori d'Enginyeria Martima (LIM-UPC), c./Jordi Girona 1-3, mòdul D1 Campus Nord UPC, 08034 Barcelona, Spain 11 07 2007 3 3 345 362 Copyright: © 2007 G. Jordà et al. 2007 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://os.copernicus.org/articles/3/345/2007/os-3-345-2007.html The full text article is available as a PDF file from https://os.copernicus.org/articles/3/345/2007/os-3-345-2007.pdf

The effects of wave-current interactions on shelf ocean forecasts is investigated in the framework of the MFSTEP (Mediterranean Forecasting System Project Towards Enviromental Predictions) project. A one way sequential coupling approach is adopted to link the wave model (WAM) to the circulation model (SYMPHONIE). The coupling of waves and currents has been done considering four main processes: wave refraction due to currents, surface wind drag and bottom drag modifications due to waves, and the wave induced mass flux. The coupled modelling system is implemented in the southern Catalan shelf (NW Mediterranean), a region with characteristics similar to most of the Mediterranean shelves. The sensitivity experiments are run in a typical operational configuration. The wave refraction by currents seems to be not very relevant in a microtidal context such as the western Mediterranean. The main effect of waves on current forecasts is through the modification of the wind drag. The Stokes drift also plays a significant role due to its spatial and temporal characteristics. Finally, the enhanced bottom friction is just noticeable in the inner shelf.

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