||Box 1:"The shape of a solute patch is affected by two transport processes: diffusion and turbulence. Turbulence stirs the patch into ever-finer filaments. As a
filament thins, the associated gradient (the concentration contrast with the background, divided by the filament width) grows. This increases the effect of
diffusion, which is proportional to the magnitude of the gradient, in erasing the gradient. There is, hence, a scale where the effects of turbulence and diffusion
balance. This scale is the Batchelor scale (primary source), (?D^2/?)^(1/4), which in the sea ranges from 30 to 300µm depending on the turbulent dissipation rate ?, the
diffusivity of the solute D, and the kinematic viscosity of seawater, ?."