Abstract
Chlorofluoromethane (F-11) and hydrographic data show that the Deep Western Boundary Current (DWBC) in the North Atlantic Ocean is a continuous feature of the mean circulation between Abaco (26.5°N) and Barbados (13°N). Two cores of high F-11 concentrations are coincident with the DWBC. The deep core located between 3200 and 4600 m transports North Atlantic Deep Water. The shallow core at 1000–1700 m and warmer than 4.1°θ transports recently formed Subpolar Mode Water. This water probably formed sometime during the 1960s and 1970s when there was reduced convection in the Labrador Sea. Classical LSW with a potential temperature of about 3.3°θ, which is found between 2000 and 3000 m, has a minimum in F-11 concentration because it has not been ventilated recently. A representative geostrophic transport for the DWBC below 1000 m is 8 × 10
6 m
3 s
−1.
