[MITgcm-support] Re: single layer run

[Ed Hill]

On Fri, 2005-05-13 at 07:15 -0700, Dimitris Menemenlis wrote:
> > I am convinced that even in the case of constant (in time) pressure
> > forcing you should end up with a steady state that is non-zero, also
> > in the case of a single layer.
> 
> Martin and Sergey, I have been following your discussion with some 
> interest.  I don't understand why a constant in time surface pressure 
> forcing would establish a non-zero circulation at steady state.  Isn't 
> the inverse barometer adjustment meant to insure that there is no such 
> circulation, i.e., that (for a flat ocean) the pressure at the bottom of 
> be constant?

Hi Martin, Sergey, & Dimitris,

Please correct me if I'm wrong, but if you have *any* viscosity, then
doesn't energy conservation ensure that a steady-state pressure forcing
(with no other forcings) must result in an asymptotic solution with zero
velocities?

With viscosity, any non-zero velocity field will be losing energy to
drag.  And a steady pressure forcing field cannot continuously supply
energy.  So the whole system must (however slowly) relax to a quiescent
steady-state.  Right?

Ed

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Edward H. Hill III, PhD
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