A comparison of transport and position between the Gulf Stream east of Cape Hatteras and the Florida Current

The Florida Current (FC) transport and Gulf Stream (GS) transport and position have been measured almost continuously for many decades in the Florida Straits at ∼27° N and for the last 20 years at ∼38° N along the Oleander line, respectively. Variations in both currents have been linked to the North Atlantic Oscillation (NAO). Here we show five different proxies for the position of the GS near the Oleander line and find all five measures internally consistent. Further, using a zonally averaged index, the local measurements prove to be good representatives of overall meridional shifting of the current (between Cape Hatteras and the New England Seamounts). The second part of the study shows that the statistical relationship between the GS position proxies and the GS and FC transports, in turn, is inversely correlated with r values of approximately –0.30, significant at the 85% level. The GS and FC transports themselves, on the other hand, are not significantly correlated. Although both position and transport for the GS are shown to be linked to the NAO, the lack of a robust relationship between the GS and the FC transports indicates that the FC does not have a detectable interannual signal downstream in the GS.