[MITgcm-support] 2D boundary conditions at the poles

[Angela Marie Zalucha]

Hi,

I am running the MIT GCM in 2D for the atmosphere (latitue and r* 
coordinates).  When I look at eta vs. latitue, I get a very huge spike in 
the second to last gridpoint from the poles.  I believe it is numerical 
and not physical.  I was wondering what the boundary conditions are at the 
poles and how to explain it.

Here's what I have for the horizontal grid:
usingSphericalPolarGrid=.TRUE.,
  delX=1*2.8125,
  delY=64*2.8125,
  ygOrigin=-90.,

The pressure is extremely low because this is Pluto!
Ro_SeaLevel=1.6,
rSphere=1180.E3,

I have seen that the Shapiro filter can affect numerical spikes in eta in 
other 2D planets, but haven't been able to modify it successfully here. 
Here's my data.shap :
  &SHAP_PARM01
  shap_filt_uvStar=.FALSE.,
  shap_filt_TrStagg=.TRUE.,
  Shap_funct=4,
  nShapT=4,
  nShapUV=4,

Does anybody have any ideas?

    Angela



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Angela Zalucha, Ph.D.
Postdoctoral Associate
Department of Earth, Atmospheric,
   and Planetary Sciences
Massachusetts Institute of Technology

Office located at Southwest Research Institute
1050 Walnut Street, Suite 300
Boulder, CO 80302
USA
(720) 208-7211


http://web.mit.edu/azalucha/www/index.html
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