… In this region the diffusivity can be interpreted as a horizontal eddy mixing in the mixed
layer. (bottom) Isopycnal effective diffusivity, which characterizes the mixing of passive
tracers such as PV in the ocean interior. The magenta contour lines show the streamwise-averaged
zonal velocity, indicating the position of the mean jet of the ACC, and mean isopycnals
appear in white. The velocity contour interval is 2 cm s −1 . … A snapshot of sea surface
height from SOSE from the same time is overlaid, with contour levels of 10 cm. …