A nested pre-operational model for the Egyptian shelf zone: Model configuration and validation/calibration

We explored the variability of the Egyptian shelf zone circulation connected to atmospheric forcing by means of a numerical simulation of the general circulation. A high resolution model grid was used at 1/60° horizontal resolution and 25 sigma layers. The simulation was carried out using the most recent version of the Princeton Ocean Model (POM). The initialised model was run the whole year of 2006 using the analysis forcing data for the same year obtained from ECMWF and MFS (Mediterranean Forecasting System, Pinardi et al., 2003). The model skills were evaluated by means of the root mean square error (RMSE) and correlations. The Egyptian Shelf Model (EGYSHM) simulation suggests the presence of an Egyptian Shelf Slope Current (ESSC), which is flowing eastward at different depths in the domain. We found that the maximum velocity of the ESSC [0.25 m/s] is located near the continental slope during the summer time, while in winter the velocity of ESSC is weaker [0.12 m/s] in the same location. The ESSC appears to be directly affected by Mersa-Matruh gyre system. EGYSHM reproduced the main region circulation patterns, especially after adding the Nile River outflow. We found that wind stress is crucial to force the circulation of the Egyptian shelf zone. EGYSHM SST was significantly correlated to satellite SST in all months at a 95% confidence limit, with a maximum of 0.9743 which was obtained in May 2006. The RMSE between EGYSHM and Argo floats salinity data was about 0.09. We compared our results with satellite altimetry to verify the positions and shapes of mesoscale features.