Abstract. Within the framework of the Copernicus Marine Environment Monitoring Service (CMEMS),
an operational wave forecasting system for the Mediterranean Sea has
been implemented by the Hellenic Centre for Marine Research (HCMR) and
evaluated through a series of preoperational tests and subsequently for 1
full year of simulations (2014). The system is based on the WAM model and it
has been developed as a nested sequence of two computational grids to ensure
that occasional remote swell propagating from the North Atlantic
correctly enters the Mediterranean Sea through the Strait of Gibraltar.
The Mediterranean model has a grid spacing of 1∕24∘. It is driven with
6-hourly analysis and 5-day forecast 10 m ECMWF winds. It accounts for
shoaling and refraction due to bathymetry and surface currents, which are
provided in offline mode by CMEMS. Extensive statistics on the system
performance have been calculated by comparing model results with in situ and
satellite observations. Overall, the significant wave height is accurately
simulated by the model while less accurate but reasonably good results are
obtained for the mean wave period. In both cases, the model performs
optimally at offshore wave buoy locations and well-exposed Mediterranean
subregions. Within enclosed basins and near the coast, unresolved
topography by the wind and wave models and fetch limitations cause the wave
model performance to deteriorate. Model performance is better in winter when
the wave conditions are well defined. On the whole, the new forecast system
provides reliable forecasts. Future improvements include data assimilation
and higher-resolution wind forcing.