[MITgcm-support] Choosing coordinate system for Adriatic sea

[Ed Hill]

On Mon, 2006-04-10 at 16:10 +0200, Andrea Cimatoribus wrote:
> Hi, I am writing again after some time, as I am working again at the
> OGS (trieste-Italy) to set up a model for the Adriatic Sea.
> I would like to have a tip about what coordinate system I should use.
> Adriatic sea is approximately a rectangle 800x300km pointing NW-SE
> (about 45° from the north), so we wanted to rotate axis to save
> computing time.

Hi Andrea,

> The questions are:
> - should we use cartesian or spherical coordinates (we have always
> used Cartesian coordinates, but on a smaller domain)?

I don't know all the implications here for your particular problem so I
can't say which is better.


> - is there any difference in the output using one or the other?

In terms of the MITgcm file formats for the output, it makes basically
no difference which coordinate system you use -- the output file formats
remain the same.  What does change file formats is whether you use the
mdsio (old-style fortran "binary blobs") or mnc (netCDF) packages and
whether you use single-cpu-io or not.


> - is there any problem in modifing ini_cori.F to rotate axis?

Not at all -- its very straight-forward!  A number of people have done
this in order to use rotated lat-lon grids.

Ed


-- 
Edward H. Hill III, PhD
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