Simulation and scaling of the turbulent vertical heat transport and deep-cycle turbulence across the equatorial Pacific cold tongue

However, virtually all observations of this deep-cycle turbulence (DCT) are from 0 degrees, 140 degrees W. Here, a hierarchy of ocean process simulations, including submesoscale-permitting regional models and turbulence-permitting large-eddy simulations (LES) embedded in a regional model, provide insight into mixing and DCT at and beyond 0 degrees, 140 degrees W. A regional hindcast quantifies the spatiotemporal variability of subsurface turbulent heat fluxes throughout the cold tongue from 1999 to 2016.

Mean subsurface turbulent fluxes are strongest (similar to 100 W m(-2)) within 2 degrees of the equator, slightly (similar to 10 W m(-2)) stronger in the northern than Southern Hemisphere throughout the cold tongue, and correlated with surface heat fluxes (r(2) = 0.7). The seasonal cycle of the subsurface heat flux, which does not covary with the surface heat flux, ranges from 150 W m(-2) near the equator to 30 and 10 W m(-2) at 4 degrees N and 4 degrees S, respectively.