Equatorial zonal jets formation

After a brief review of oceanic mid -latitude zonal jets observations and of their currently proposed formation mechanisms, the characteristics of oceanic equatorial zonal jets are presented. A new mechanism for zonal jets formation is proposed based on the destabilization of short Mixed Rossby Gravity waves, providing a rationale for the difference of scales observed in the Pacific and in the Atlantic deep equatorial jets. Results of numerical simulations performed on the Earth Simulator are presented to validate the analytical theory