Turbulent eddy diffusion takes energy up from the ocean rather than down from the surface because warm water is lighter than colder water. (scienceofdoom.com)
The downward path coming from eddy diffusion and the downward flow to the northern polar vortex at the tale end of planetary and gravity waves. (landscheidt.info)
Waters with longer τ are spread across the deep oceans by the «diffusive conveyor» and, by τ ∼ 3000 years, organized into a characteristic deep - North - Pacific pattern that is dominated by eddy diffusion. (pubs.giss.nasa.gov)