Eqn.(3) (discussed in the theory section) asserts that the restratification time-scale falls as the ambient stratification increases. The following figure shows a vertical temperature section from an experiment in which the ambient stratification was chosen to more closely approximate that which is characteristic of the Gulf of Lions (the upper 500m had N=2x10-3s-1, while beneath N=0.5x10-3s-1 as in our reference example. The heightened near-surface stratification accelerates collapse in surface layers, capping over the homogonised interior of the chimney in a matter of days. It seems plausible therefore that observations of rapid near-surface restratification reflect the same mechanism expressed in Eqn.(3) (discussed in the theory section). That is the stronger ambient stratification drives vigorous baroclinic eddies which rapidly break up and disseminate the anomalously dense water at the surface of the convection region.
Compare the figure below (after 20 days of integration) with the north-south temperature section after 20 days in the reference experiment. For the purposes of comparison the contour interval is 0.05 degrees; the same for each figure.
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