Deep circulation in the equatorial Atlantic Ocean

In the Atlantic Ocean, the northward export of warm surface water is compen sated by a southward flow of cold North Atlantic Deep Water (NADW). The NAD W is transported southward along the American continental margin within the Deep Western Boundary Current (DWBC). Some tracer and float observations h ave shown that part of the DWBC water flows eastward along the equator. Her e we present three meridional velocity sections which give an instantaneous image of the top-to-bottom zonal circulation along the equatorial Atlantic . They reveal the presence of Equatorial Deep Jets (EDJs) between 1 degrees 30'N and 1 degrees 30'S, alternating eastward-westward currents with short vertical scale, surrounded by columns of eastward currents (the Extra Equa torial Jets or EEJs) at 2 degreesN and 2 degreesS. In addition to direct ve locity measurements, tracer distributions give indications of water-mass fe eding of the EDJs and EEJs by the DWBC.