Eddy diffusivity in the equatorial and tropical Pacific Ocean diagnosed from an ocean state estimate

We present analysis of eddy diffusivity in the equatorial and tropical Pacific Ocean based on18 years of output from a 1/6 degree ocean state estimate. The data product from the Estimating the Circulation and Climate of the Ocean (ECCO) group at JPL is a free running model with initial conditions, boundary conditions and parameterizations fit to the available satellite, buoy, float, and ship data using a Green’s function approach. The average surface diffusivity in the tropical Pacific estimated using salinity is found to be around 4000 m²/s, with salinity behaving as a passive tracer. We explore the latitudinal dependence of the eddy diffusivity and compare the implied eddy stresses to the wind stress forcing.