The transatlantic hydrographic section along 7°30N is of great interest for climate studies as it represents a crucial region of the global overturning cell. It has been previously surveyed twice, during the 1957 International Geophysical Year and during 1993 as part of the World Ocean Circulation Experiment program under the denomination of A06 line. Comparison of these realizations revealed a net warming of the intermediate and upper deep waters, and cooling of the bottom water. A third occupation of this section, during spring 2010, allows us to update the long‐term hydrographic variations in the tropical water masses. Temperature and salinity changes at constant pressures are partitioned into changes on isopycnal surfaces and changes due to the vertical movement of the isopycnals in order to identify the controlling mechanisms. The results are discussed in the context of previous variations found over the North Atlantic

I Encuentro de la Oceanografía Física Española (EOF), 13-15 de octubre 2010, Barcelona

Peer Reviewed