CFM (CCl3F or freon F-11 and CCl2F2 or freon F-12) measurements were made on board the R.V. Atalante as part of a quasi-synoptic survey of the tropical Atlantic Ocean. The work was carried out during the CITHER 1 cruise, part of the French CITHER program (Circulation THERmohaline) between January and March 1993. Two zonal sections at 4°30 S and 7°30N (the A7 and A6 WOCE sections) and two meridional sections at 35°W and 3°50 W were sampled for CFMs between the African and South American continents. The results reported here deal primarily with the North Atlantic Deep Water. The CITHER 1 sections were made just 10 years after the first CFMs snapshot of the tropical Atlantic ocean obtained during the Transient Tracers in the Ocean Program.The detection limit was approximately 0.0025 pmol.kg-1 for both F-11 and F-12. This is sufficient to allow the determination of “apparent” ages and dilution factors for the freon- enriched tongues of the Upper and Lower North Atlantic Deep Water (UNADW centered around 1600 m and LNADW centered around 3800 m).Both zonal sections clearly show the propagation of UNADW into the eastern basin. The eastern meridional section at 3°50W shows the CFM cores extending from 4°S to 3°N with a maximum around 2°S. From the equatorial CFM ratios in the eastern basin, we estimate an eastward velocity close to 2 cm/s.The CFM distributions at the levels of the UNADW and LNADW show a large variability, probably linked to northern and southern deep recirculation gyres. In both sections, CFM enriched cells are clearly the result of reversed currents.The net decrease of CFM in the LNADW between 7°30N and 4°30S is partly the result of the bifurcation of the deep flow north and at the equator. This is confirmed by data taken in November 1992 in the region of the Equatorial Romanche Fracture Zone by the ROMANCHE 2 cruise. The influence of Antarctic Bottom Water is noticeable along the South American continent in the southern section. There is no evidence, through CFM data alone, for a northward flow of this “young” bottom water mass, which is probably blocked by the topography near the sampled areas.
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