[Mitgcm-support] RE: detatfreesurf == deltatracer

[mitgcm-support at dev.mitgcm.org]

BTW - i keep meaning to ask, does it really change many of the numbers?
aren't
most expts (xcept global) synchronous time-stepping?

chris

-----Original Message-----
From: adcroft at localhost.localdomain
[mailto:adcroft at localhost.localdomain]On Behalf Of Alistair Adcroft
Sent: Tuesday, June 25, 2002 8:28 PM
Cc: support at mitgcm.org
Subject: Re: detatfreesurf == deltatracer


Jean-Michel Campin wrote:
> By the way, deltaT_freesurf is not the time step of
> barotropic mode but only the time step of the free
> surface equation d.eta/dt = -Div.U.
> the equivalent time step of the barotropic mode is
> in fact the square root of deltaT_freesurf*deltaT_Mom

Good point - it means the damping is only a faction of what
Chris would estimate based on wave speed with dt=1 day.

BTW, the rigid-lid (deltaTfreesurface=Infty) is also stablizes
the global_ocean expt with dt=86400.

A.