Mean and standard deviation of the far-field vertical diffusivity (K in cm^{2} s^{−1} averaged over the last 500 m of the water column 3500 m ≤ z ≤ 4000 m) for various values of the parameter L_{s} in (12). The mean K agrees well with oceanic measurements of pelagic vertical diffusivity, and this result is not sensitive to the value of the parameter. But deviations from this mean increase with L_{s}, i.e., as the nonlocality of the saturation increases.