Résumé
This paper presents CFC and nontransient tracer observations in the western equatorial Atlantic Ocean on repeated sections along 7 deg 30 min N, the 35 deg W meridian, and a transect crossing the Ceara Rise. Three World Ocean Circulation Experiment cruises were carried out in this area, during February-March 1993 (CITHER 1) and September-October 1995 and April-May 1996 (ETAMBOT 1 and 2). Together with the tracer data, the direct current measurements are used to deduce the circulation pathways. The data confirm the principal circulation features of the Upper North Atlantic Deep Water within the area. The Deep Western Boundary Current flows southward along the continental slope, while, adjacent to the DWBC, there is a northward flow corresponding to the DWBC recirculation, whose origin appears variable. The largest variability is observed along the 35 deg W meridional section, where the DWBC bifurcates eastward north of 3 deg S, but the eastward equatorial flow does not appear to be permanent. At the Middle North Atlantic Deep Water level, CFC distributions exhibit the most important contrast between waters of northern and southern origin. (Author)