A Sigma-Coordinate Primitive Equation Model for Studying the Circulation Pattern in the South Caspian Sea

The aim of this study was to design and develop a three-dimensional numerical baroclinic model with the ability to accept complex bottom topography and variable wind in space and time to investigation wind-induced current at 10 layers in the south Caspian Sea. The finite difference method Was used for numerical solution of the primitive equation in spherical Sigma pressure coordinate system on staggered modified Arakawa C grid. The wind data available from ECMWF ERA 15 data sets and the bathymetric data obtained from the GEBCO data sets with spatial resolutions of 0.125o were utilized in the model. The result shows there are found a cyclonic eddy in middle of the basin and an anticyclonic current in close of the western coast that continued over the year. In addition, the circulation in the extensive continental shelve near the eastern coast is especially sensitive to wind direction and speed Also the maximum of surface current always take place in this area.