A diagnostic study of interpentadal variability in the North Atlantic Ocean using a finite element model

Previous work has shown that major changes to the thermohaline structure of the North Atlantic occurred between the pentads 1955-1959 and 1970-1974 and that these changes led to significant changes in the transport of the Gulf Stream system. Here we expand on these results by examining the changes in North Atlantic transports for the entire period 1950-1994. Based on temperature and salinity data from the Lozier climatology, and the deviations from this during different periods since 1950, the thermohaline densities are reconstructed. The circulations associated with these different periods are then derived using a diagnostic finite element model. The results show significant decadal variability in transports in both the sub-tropical and sub-polar gyres.