The CMEMS Mediterranean and Black Sea analysis and forecasting physical systems: description and skill assessment

Abstract

The Mediterranean and Black Sea operational forecasting systems are developed and continuously improved in the context of the Copernicus Marine Environment and Monitoring Service (CMEMS). The two systems operationally produce analyses and 10-days forecasts of the main physical parameters (Temperature, Salinity, Sea Level, Currents, Mixed Layer Depth) with a resolution of about 4.5km in the horizontal over 141 vertical levels in the Mediterranean Sea, and about 3km in the horizontal over 31 vertical levels in the Black Sea. The hydrodynamic numerical solutions are based on the NEMO (Nucleus for European Modelling of the Ocean) model coupled to a 3D variational data assimilation method (3DVAR) able to assimilate in-situ temperature and salinity profiles, satellite along-track sea level anomaly and sea surface temperature (in the Mediterranean Sea a nudging to satellite SST-L4 dataset is provided). The Mediterranean system is also 2-way online coupled with the WW3 (WaveWatch3) wave model to better represent the surface drag coefficient. The two systems are forced by 1/8o degree ECMWF (European Centre for Medium-range Weather Forecasts) atmospheric fields.

The systems are validated in near real time and the quality of the products is monitored through regional websites (http://medfs.cmcc.it/ and http://bsfs.cmcc.it/) showing the analysis and forecast field maps at different depths (in case of 3D variables) as well as a weekly validation of model analysis compared with available observations.

The focus of this work is to present the latest modelling system upgrades and the related improvements achieved by showing the model skill assessment including comparison with in-situ and satellite observational datasets.