References:
- Gridspec: A standard for description of grids used in Earth System models
- Mosaic Tool User Guide
- A Guide to Grid Coupling in FMS
- FRE-NCtools
- Python gridtools
The Flexible Modeling System operates from the same directory (INPUT
). This is defined in
MOM_input
variable INPUTDIR
. The MOM_input
file is defined in input.nml
.
The top level file is the grid_spec.nc
. This file links to three types of files:
- Mosaics
- Ocean topography
- Exchange grid files
A quick setup entails using the same ocean_mosaic.nc
file for atmosphere, land and ocean mosaics.
- atm_mosaic_file =
ocean_mosaic.nc
- lnd_mosaic_file =
ocean_mosaic.nc
- ocn_mosaic_file =
ocean_mosaic.nc
- All should reside in the
INPUT
directory and the mosaics should specify the directory as./
.
The ocean topographic file can be named anything, but the default name is ocean_topog.nc
.
- ocean_topog_file =
ocean_topog.nc
- This file typically resides in the
INPUT
directory which is specified using./
.
For the quick case, three files are specified for tile1
. The general pattern is:
- atmos X land
- atmos X ocean
- land X ocean
The included points are usually correspond to those requested in the 2nd element. The land points
are exchanged in atmosXland
and the ocean points are exchanged in atmosXocean
and landXocean
.
This defines the name of the mosaic without the extension: ocean_mosaic
. The gridlocation
defines the location of this file which should reside in the INPUT
directory and should be
specified as ./
.
Each mosaic then points to respective gridfiles
and gridtiles
. In the quick case, there is
only one of each.
- gridfiles =
ocean_hgrid.nc
- gridtiles =
tile1
Within the netCDF file for MOM6 grids the following descriptions of variables and dimensions:
- Dimensions
- nx, ny : grid centers
- nxp, nxp : grid verticies
- The supergrid is twice the horizonal resolution.
- The supergrid contains all the staggered points, but the model only solves equations for the actual grid.
- When talking about the resolution of a MOM6 grid, the convention is to talk about the resolution of the grid not the supergrid.