A multi-institution field experiment is designed to study the spatial and temporal evolution of North Brazil Current (NBC) retroflection and the separation of rings from the retroflection. The physical structure of the rings after separation from the NBC, including their sizes, vertical structure, horizontal swirl velocities and the volume of South Atlantic water they trap and transport will be determine. The observations will combine complementary techniques: an inverted echo sounder array within satellite altimeter tracklines, current, temperature and salinity mooring, Lagrangian surface drifters and subsurface floats and shipboard surveys.
