EFFECT OF REDUCED DIFFUSION ON SURFACE WIND AND WAVE-FIELDS

Horizontal diffusion is used in meteorological models to reduce noise in the shorter spatial scales and to increase numerical stability. In turn, this affects the surface wind distribution. A series of tests on real situations in the Mediterranean Sea has been done to explore the practical consequences on wind and wave fields. The results indicate a substantial reduction of the peak values, particularly in areas with strong spatial gradients, and a general smoothing of the fields, more evident where these are dominated by the local orography.