COMPARISON OF TOPEX-POSEIDON ALTIMETER DATA WITH GENERAL-CIRCULATION MODEL IN THE MEDITERRANEAN

Outputs of a primitive-equation numerical model of the Mediterranean f orced by 6-h ECMWF winds are compared with Topex-Poseidon surface topo graphy measurements in 1993. The comparisons show a fair qualitative a greement on the structure of the general surface circulation and on a number of large-scale features. The high-frequency wind forcing is tho ught to objectively contribute to the control of the model trajectory. There is good agreement on the variations of the surface transport of the Algerian Current and Mid-Mediterranean jet. As expected, the medi um model resolution (1/4(0)) does not allow for a satisfying represent ation of the smaller scales in the model. The limited resolution accou nts for large errors on the response to wind forcing, on the spindown of seasonal gyres, and on th instabilities and meanders of coastal cur rents. Nevertheless, this study can serve as a reference for a future step involving higher resolution modelling and assimilation.