[MITgcm-support] Curvilinear grid file formats

[Jeffery R Scott]

Hi all,

Was trying to convert an existing curvilinear setup which used  #define OLD_GRID_IO to the “new" compact format. This is a single domain of 210x192. EXCH2 is not activated.
Initially setting up for a single proc/tile.

I found an old thread (http://mailman.mitgcm.org/pipermail/mitgcm-support/2013-July/008420.html) which addressed my first problem,
namely that the new compact format requires fields (Nx+1,Ny+1) whereas old is (Nx,Ny). FWIW I did not get any difference (in mach prec)
when I filled in the Nx+1 and Ny+1 fields for XG and YG (which was unclear in thread discussion). A bit curious that the new way requires angleCS and angleSN
but not required in the old way.

However when I went to 80 procs/mpi the code wanted 80 grid files with extensions face001.bin, face002.bin etc. rather than accepting a global file
(I specify horizGridFile). I did not see a way to get around this in the code, is there?

As an aside, most things in MITgcm with a switch named as *OLD* indicate something obsolete (often inferior) and kept for backward compatibility.
In this instance, it seems OLD_GRID_IO might actually be the easiest way to set up this grid, and perhaps a more appropriate name should
be chosen for this CPP option?

Jeff
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.mitgcm.org/pipermail/mitgcm-support/attachments/20200804/dd9f6bcb/attachment.html>