عنوان مقاله [English]
The subject of this study is 3D modeling of density changes and double diffusion of salinity and temperature in a marine rectangular basin with closed boundaries and none-level bottom on longitude: 47º to 58º E and latitude: 24º to 30º N. In the area of the study every horizontal layer has regular mesh grid points. In this study the lattice that is applied is modified Arakawa C lattice and spatial grid distance in both east and north is equal to 0.5º and in vertical with respect to type of vertical coordinate, it is equal to 0.1 in sigma scale. Distance of grids is considered as long as 0.5-degree Longitude and Latitude. It is considered in 5 layers in spherical coordinate with sigma vertical component. In order to Numerical calculation of every parameter used in governing equations, equation should be discretize by special mathematical scheme, and wind blow is considered steady all over basin surface during the 4 days. Results show quality of changes in diffusion of temperature and salinity of each layer along longitude and latitude.