Full‐Depth Global Estimates of Ocean Mesoscale Eddy Mixing from Observations and Theory

Mixing by mesoscale eddies profoundly impacts climate and ecosystems by redistributing and storing dissolved tracers such as heat and carbon. Eddy mixing is parameterized in most numerical models of the ocean and climate. To reduce known sensitivity to such parameterizations, observational estimates of mixing are needed. However, logistical and technological limitations obstruct our ability to measure global time‐varying mixing rates. Here, we extend mixing length theory with mean‐flow suppression theory, and first surface modes, to estimate mixing from readily‐available observational‐based climatological data, of salinity, temperature, pressure and eddy kinetic energy at the sea surface. The resulting full‐depth global maps of eddy mixing can reproduce the few available direct estimates and confirm the importance of mean‐flow suppression of mixing. The results also emphasize the significant effect of eddy surface intensification and its relation to the vertical density stratification. These new insights in mixing dynamics will improve future mesoscale eddy mixing parameterizations.