The improvement of modelled wind and wave fields with increasing resolution

Abstract We have simulated a number of periods using different resolutions of the ECMWF meteorological model. Then we have explored how the quality of the surface wind and wave model results varies with the resolution. The comparisons have been done in the oceans and in the Mediterranean Sea, using measured data from buoys and satellite. At the highest resolution we have used, T799 or 25 km, the biases in the oceans reduce to very small values of the order of a few percent. In enclosed seas, represented in this case by the Mediterranean, the errors decrease with increasing resolution, but a substantial underestimate still remains. The maximum values of both the wind speeds and the wave heights increase with resolution. However, the suggestion is that even T799 fails to model properly the highest peaks of the storms, a fact possibly due to the inaccurate description of physics in these extreme events. This seems particularly true in the case of a cyclone in the Bay of Bengal.