SOFAR float observations of an intermediate-depth eastern boundary currentand mesoscale variability in the eastern tropical Atlantic Ocean

Two neutrally buoyant SOFAR floats vigorously looped and meandered at depth s of 950-1150 m in the eastern tropical Atlantic Ocean. The float trajector ies illustrate a poleward how along the tropical eastern boundary and signi ficant intermediate-depth mesoscale variability in the low-latitude eastern basin. One float, caught within an energetic cyclonic eddy near the easter n boundary, looped cyclonically 14 times while translating 600 km northward parallel to the African coastline. A second float. launched near the Mid-A tlantic Ridge, meandered eastward with a Lagrangian zonal wavelength of 400 km and meridional amplitude exceeding 200 km. Satellite infrared imagery i ndicates that horizontal shear associated with the system of near-surface z onal equatorial currents may contribute to the observed intermediate-depth variability.