Rossby wave radiation in the Cape Verde frontal zone

Abstract

Radiating baroclinic Rossby waves excited through instability of the Cape Verde frontal zone are proposed as a mechanism for the generation of mesoscale variability at middepth (1000 m) in the southeastern North Atlantic basin. Linear quasigeostrophic theory is applied to an idealized front representative of the Cape Verde frontal zone to demonstrate that the front is unstable to modes that may radiate away from the frontal region as baroclinic Rossby waves. Evidence for the existence of these waves is obtained from an eddy-resolving, basin-scale general circulation primitive equation model. In addition, the model fields are used to identify characteristic signatures of the waves in terms of quantities that may be directly observed in the ocean. -from Authors