Scale and Space Dependent Horizontal Eddy Diffusivity at the Global Surface Ocean

Sea surface temperature (SST) and idealized temperature tracer based estimates of horizontal diffusivity at the ocean surface. See https://doi.org/10.5281/zenodo.4126315 for the code to reproduce these estimates.

There are two files which include the following

KxKy_SST_MITGCM_025.nc

SST based estimates are based on 35 years of satellite SST data (1982-2017) and we have divided the data in 30 chuncks, both using a 5 year and 10 year sub-sampling. The 'ens' dimension marks these chuncks whereas 'lat' and 'lon' mark the two Cartesian directions (latitude and longitude). Note that 'ens' can be also viewed as time.

There are two fields 'Kx' and 'Ky' for each dataset ('SST' for the OI-SST based estimates or 'MITGCM' for the tracer simulation based estimates) and length of sub-sampling. 'Kx' is the diffusivity in 'lon' direction whereas 'Ky' is the diffusivity in 'lat' direction. Data is given at 0.25° resolution, but the effective resolution is twice that i.e. 0.5°.

K_SST_MITGCM_2deg.nc

Scale dependent estimate of the diffusivity magnitude i.e. \(K= \sqrt{K_xK_y}\) . As for the other data, here as well the estimates are done using 5 year and 10 year sub-sampling, and all the data is interpolated to a common 2° by 2° global grid. The coordinate 'dg' defines the scale in degrees. Note that again the effective resolution of the estimates is twice the 'dg'.