Anatomy and decadal evolution of the Pacific Subtropical-Tropical cells (STCs)

The STCs consist of equatorward pycnocline transports in the ocean interior and in the western boundary current, equatorial upwelling, and poleward flow in the surface Ekman layer.

The interior pycnocline transports exhibit a decreasing trend after the mid-1970s, in agreement with observational transport estimates, and are largely anticorrelated with both the Ekman transports and the boundary current transports at the same latitudes. The boundary current changes tend to compensate for the interior changes at both interannual and decadal time scales. The meridional transport convergence across 9 degrees S and 9 degrees N as well as the equatorial upwelling are strongly correlated with the changes in sea surface temperature (SST) in the central and eastern equatorial Pacific.