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The spatial and temporal variability of the surface circulation in the Western Mediterranean (WMED) is examined using an eddy permitting numerical simulation (NM8) and satellite altimetry records over a 15 year period (1993-2007). First, the analysis of the mean currents provided by the model reveals an overall circulation scheme that presents minor discrepancies with observations. Secondly, the variability is assessed by computing the mean Eddy Kinetic Energy (EKE). Both datasets (altimetry and NM8) exhibit comparable levels of EKE and confirm that the Alborán and the Algerian basins are the regions of maximum EKE. Altimetry and NM8 reproduce the Western and Eastern Alborán gyres as well as the high EKE regions along the path of the Algerian current. Finally, the principal patterns of the WMED surface circulation are estimated from standard EOF analysis in three sub-basins of high interest: the Alborán Basin, the Algerian Basin and the North-Western Mediterranean. NM8 shows an exceptional performance when compared to altimetry for the spatial pattern and seasonal variability of the first EOF mode. For what concerns the second mode, the spatial patterns are very similar for altimetry and NM8 in all regions, although some differences are observed for the interannual variability of the temporal amplitude.