Abstract
Multiyear turbulence measurements from oceanographic moorings in the
equatorial Atlantic and Pacific cold tongues reveal similarities in deep
cycle turbulence (DCT) beneath the ML and above the core of the
Equatorial Undercurrent (EUC). Diurnal composites of turbulence kinetic
energy dissipation rate, $\epsilon$, clearly show the
diurnal cycles of turbulence beneath the ML in both cold tongues.
Despite differences in surface forcing, EUC strength and core depth, DCT
persists at all three sites, and is consistent between the sites.
Time-mean values of $\epsilon$ at 30 m depth are nearly
identical at all three sites. Variations of averaged values of
$\epsilon$ in the deep cycle layer below 30 m range to
a factor of 10 between sites. A proposed scaling in depth that isolates
the deep cycle layers and of $\epsilon$ by the product
of wind stress and current shear collapses vertical profiles at all
sites to within a factor of 2.