[en] A free-surface, three-dimensional, primitive equation model has been implemented with a horizontal resolution of 4.6 km to study the ocean circulation in the Gulf of Lions at time scales ranging from weeks to seasons. Numerical experiments have been conducted, in which the regional model is nested into a basin-scale model of the whole western Mediterranean. The global model is operated with a relatively coarse resolution (16 km) and provides boundary conditions at the open-sea boundaries of the regional domain. There is, however, no Feedback loop from the regional to the global model. The simulations are consistently driven with atmospheric fluxes computed from the output of the French PERIDOT meteorological forecasting system, between August 1988 and 1989. In addition to the initial conditions, in situ measurements of temperature and salinity are assimilated in the simulation of the general circulation, adopting a simple nudging technique to prevent an excessive drift of the model against climatology. The response of the regional model below and above the thermocline is discussed in the context of the prevailing meteorological situations. Some experiments give indications that a double-gyre system may develop from wind regimes that exhibit a cyclonic/anticyclonic wind stress curl. Advection-diffusion of passive tracers are also examined on the basis of the local hydrodynamic features, because this work has been conceived with the aim of determining the physical conditions in which ecological and biochemical processes develop at the interface between river mouths and the open ocean. (C) 1997 Elsevier Science Ltd.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Beckers, Jean-Marie ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie physique
Brasseur, P.
Nihoul, Jacques ; Université de Liège - ULiège > Services généraux (Faculté des sciences) > Relations académiques et scientifiques (Sciences)
Language :
English
Title :
Circulation of the western Mediterranean: From global to regional scales
Publication date :
1997
Journal title :
Deep-Sea Research. Part II, Topical Studies in Oceanography
ISSN :
0967-0645
Publisher :
Pergamon Press - An Imprint of Elsevier Science, Oxford, United Kingdom
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