ON A PHYSICAL-MECHANISM OF THE FORMATION OF THE GULF-STREAM RECIRCULATION GYRE

The formation of the recirculation gyre of the western boundary curren t due to the transport of the relative vorticity by the boundary curre nt is examined. The regional barotropic numerical model is suggested f or the quantitative analysis of the proposed mechanism. The domain of integration and the corresponding boundary conditions are chosen to mo del the mechanism in the simplest way. The formation of the prominent recirculation gyre is shown when the influx of the relative vorticity into the domain is on the same order as that of the planetary vorticit y, and the coefficient of horizontal turbulent diffusion A(L) is equal to 10(7) cm(2)/s. The increase of the coefficient A(L) destroys the r ecirculation gyre. The reasons for the southward deflection of the nor thern boundary current are discussed.