[MITgcm-support] noise again, coarse resolution

[Patrick Heimbach]

Hi Martin,

I presume it's relatively coarse-res(?).
Definetely worth trying the one thing you haven't,
i.e. use C-D scheme.

-p.



On Tue, 2006-05-02 at 12:08, Martin Losch wrote:
> Hi there,
> 
> I am trying to reproduce the results of
> Pacanowski and Gnanadesikan 1998: Transient response in a z-level  
> ocean model that resolves topography with partial-cells. MWR, Vol  
> 126, No 12, December 1998.
> with the MITgcm (checkpoint58b_post). I tried to copy the  
> configuration as closely as possible (running into all sorts of  
> trouble, there is a typo in the equation for lambda and the density  
> perturbation may be too large), but the model becomes unstable after  
> 50 days or so (visible in a peak in kinetic energy and a deltaX  
> pattern in temperature). I tried free slip, no slip, JamartWetPoints,  
> staggering the time step (but not CD-scheme), different advection  
> schemes, increased friction by factor 10, timesteps between 3600 and  
> 900 seconds, but nothing improves the situation. I have attached my  
> configuration (code and input directory, need to regenerate input  
> files with matlab), which is very simple and takes about 60sec to  
> run. Can anybody see what I am doing wrong?
> 
> Martin
> 
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Patrick Heimbach   Massachusetts Institute of Technology
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