35.2.2.3 Diffusivity and the basic tunable parameter

Once the length and time scales are computed, the diffusivity is given by

$$\kappa = \alpha \, L^{2}_{vmhs} \, T^{-1}$$ (35.101)

where $\alpha$ is a tuning parameter. $\alpha = 0.015$ was found by VMHS to be optimal for fitting their model experiments. This value is also used in the Hadley Centre ocean model. It is the default value in MOM, and can be changed by setting the namelist parameter $vmhs\_alpha$.