Orientational effects in geophysical fluid dynamics

The approach, accounting the interaction between essentially different scales of turbulent fluid motions on a rotating sphere, is developed. Representation of the large-scale oceanic circulation as a turbulent flow with orientational effects due to synoptic (mesoscale) eddies is the basis of this technique. The scale of these eddies is much less than that of the considered problem, their energetic significance however is important. Such representation leads to employment of nontrivial angular momentum equation, i.e. to micropolar or asymmetrical hydrodynamics. It allows to define a function which would characterize the averaged vorticity of mesoscale (subgrid) motions and does not relate to the mean flow vorticity. Using this parameterization, the calculations with barotropic and 2-layer global ocean models have been carried out. The model results do show an increase of basic ocean gyre transports.