The Squeezing of Eddies through Gaps

The islands of the Lesser Antilles present a porous meridional barrier to North Brazil Current (NBC) rings. To better understand if, when, and how a NBC ring could be squeezed into the Caribbean Sea through such a gappy barrier, the encounter of a westward drifting eddy with a porous meridional wall is considered. First an eddy encountering a single aperture is modeled. To do so, both an analytical model and a reduced-gravity primitive equations numerical model are used. This was followed by numerical experiments that explored eddy collisions with barriers containing many gaps. In all of these models, the collisions were forced by either or a steady advection through the gap(s).