The shallow thermohaline circulation of the Red Sea
Deep-Sea Res., 44, 1355-1376, 1997.
The circulation of the Red Sea is driven by strong surface evaporation, but
the buoyancy budget alone cannot determine the circulation and thermohaline
structure. The circulation could be rapid with weak stratification or slow
with strong stratification. These possible states are examined in the
dynamical framework of Phillips' similarity model applied to the upper 140m.
A large eddy viscosity in the return flow between 70 and 140m is required
for the solution to match the observed stratification. The circulation for
this solution is slow in accord with the weak geostrophic currents observed
in the Red Sea and partially justifies the neglect of rotation. The
internal viscous force required to match the model to observations seems
too big to be a proxy for bottom friction on the sloping sides, though the
mismatch is not large at the southern end of the Sea if the model is
modified to allow for decreasing width with depth. The model may also be
used to confirm that forcing by the wind stress is of secondary importance.
Overall the Red Sea appears not to be overmixed, though the model displays
the counterintuitive result that increased vertical mixing increases the
buoyancy difference between surface and bottom.
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