[MITgcm-support] shapiro filter on partial domain

[Jean-Michel Campin]

Hi Bill,

When applying the shapiro filter on Theta or Q, the masks from
the dynamical grid (i.e. maskW, maskS & maskC) are used 
to avoid this kind of boundary effect next to topography.
You may try to use the same technique to filter land-points surface
temperature.
You can come to talk how to implement this, if you want.

Jean-Michel

On Wed, Oct 26, 2005 at 05:08:21PM -0400, William Boos wrote:
> I am running a 2D (latitude-height) version of the mitgcm, atmospheric
> version, with a land surface covering part of the domain.  I have found it
> is necessary to shapiro filter the land surface temperature to eliminate
> instability due to 2-gridpoint waves in this field.  However, when I do this
> I get an instability in the 2 to 3 land grid cells adjacent to the ocean.  I
> am guessing that this occurs when the shapiro filter tries to act on the
> surface temperature discontinuity which arises between ocean and land
> gridpoints (the ocean is held at fixed SST).
> 
> How can I run the shapiro filer on the land surface only, specifying the
> appropriate horizontal boundary conditions at the coast?  Or is there some
> other solution to this situation?
> 
> Regards,
> Bill Boos
> 
> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mitgcm.org/mailman/listinfo/mitgcm-support