make_hgrid

Structured YAML to run make_hgrid is validated by JSON Schema and requires the make_hgrid: block, described below. If make_hgrid is to be run via a batch system, the platform: block, described here, is also required.

Important

YAML keys and their descriptions are taken largely verbatim from the make_hgrid tool source code, available here. Best effort has been made to ensure its requirements are followed in the schema but users must ensure their parameters are valid to the source tool.

Here is a prototype UW YAML make_hgrid: block, explained in detail below:

make_hgrid:
  config:
    do_schmidt: true
    great_circle_algorithm: true
    grid_name: C96_foo
    grid_type: gnomonic_ed
    halo: 1
    iend_nest:
      - 87
    istart_nest:
      - 10
    jend_nest:
      - 78
    jstart_nest:
      - 19
    nest_grids: 1
    nlon:
      - 192
    parent_tile:
      - 6
    refine_ratio:
      - 2
    stretch_factor: 1.0001
    target_lat: 38.5
    target_lon: -97.5
  execution:
    batchargs:
      nodes: 1
      stdout: /path/to/runscript.out
      walltime: "08:00:00"
    executable: /path/to/make_hgrid
  rundir: /path/to/run/dir

UW YAML for the make_hgrid: Block

execution:

See this page for details.

config:

Describes the required parameters to run a make_hgrid configuration.

grid_type:

grid_type is the primary required key that defines the grid and additional required keys. It is specified with one of the following recognized key words:

Table 1 Grid Types and Requirements

Grid Type	Requirements
beta_plane_grid	For setting geometric factors according to beta plane. f_plane_latitude needs to be specified.
conformal_cubic_grid	nratio is an optional argument.
f_plane_grid	For setting geometric factors according to f-plane. f_plane_latitude must be specified.
from_file	my_grid_file must be specified.
gnomonic_ed	Equal distance gnomonic cubic grid.
simple_cartesian_grid	xbnds, ybnds must be specified to define the grid bounds location and grid size. simple_dx and simple_dy must be specified to specify uniform cell length.
spectral_grid	No other optional or required arguments.
regular_lonlat_grid	nxbnds, nybnds, xbnds, ybnds must be specified to define the grid bounds.
tripolar_grid	nxbnds, nybnds, xbnds, ybnds must be specified to define the grid bounds.

angular_midpoint:

If specified, when grid_type is from_file and the input is a NetCDF file, then the supergrid face midpoint coordinates are simply and independently (the lat independently from the lon) calculated as simple angular midpoints from the model grid coordinates.

center:

Specify the center location of grid.

do_cube_transform:

Set to re-orient the rotated cubed sphere so that tile 6 has ‘north’ facing upward. When do_cube_transform is set, the following must be set: stretch_factor, latget_lon, and target_lat.

do_schmidt:

Set to do Schmidt transformation to create a stretched grid. When do_schmidt is set, the following must be set: stretch_factor, target_lon and target_lat.

dlat:

Nominal resolution of meridional regions.

dlon:

Nominal resolution of zonal regions.

great_circle_algorithm:

When specified, great_circle_algorithm will be used to compute grid cell area.

grid_name:

Specify the grid name.

halo:

Halo size is to make sure the nest, including the halo region, is fully contained within a single parent (coarse) tile. It only needs to be specified when nest_grids is set.

lat_join:

Specify latitude for joining spherical and rotated bipolar grid. Default value is 65 degrees.

my_grid_file:

Read grid information from ‘my_grid_file’. The file format can be ascii file or netcdf file. Required when grid_type is from_file.

nest_grids:

Set to create this # nested grids as well as the global grid. This option could only be set when grid_type is gnomonic_ed.

istart_nest:

Specify the list of starting i-direction index(es) of nest grid(s) in parent tile supergrid(Fortran index).

iend_nest:

Specify the list of ending i-direction index(es) of nest grids in parent tile supergrid(Fortran index).

jstart_nest:

Specify the list of starting j-direction index(es) of nest grids in parent tile supergrid(Fortran index).

jend_nest:

Specify the list of ending j-direction index(es) of nest grids in parent tile supergrid(Fortran index).

non_length_angle:

When specified, will not output length(dx,dy) and angle (angle_dx, angle_dy).

nlat:

Number of model grid points(supergrid) for each meridinal regions of varying resolution.

nlon:

Number of model grid points(supergrid) for each zonal regions of varying resolution.

nxbnds:

Specify number of zonal regions for varying resolution.

nybnds:

Specify number of meridinal regions for varying resolution.

nratio:

Specify the refinement ratio when calculating cell length and area of supergrid.

out_halo:

Extra halo size data to be written out. This is only works for gnomonic_ed.

parent_tile:

Specify the list of the parent tile number(s) of nest grid(s).

refine_ratio:

Specify the list of refinement ratio(s) for nest grid(s).

rotate_poly:

Set to calculate polar polygon areas by calculating the area of a copy of the polygon, with the copy being rotated far away from the pole.

shift_fac:

Shift west by 180/shift_fac. Default value is 18.

simple_dx:

Specify the uniform cell length in x-direction for simple cartesian grid.

simple_dy:

Specify the uniform cell length in y-direction for simple cartesian grid.

stretch_factor:

Stretching factor for the grid.

target_lat:

Center latitude of the highest resolution tile.

target_lon:

Center longitude of the highest resolution tile.

verbose:

Will print out running time message when this is set. Otherwise the run will be silent when there is no error.

xbnds:

Specify boundaries for defining zonal regions of varying resolution. When tripolar is present, also defines the longitude of the two new poles.

ybnds:

Specify boundaries for defining meridional regions of varying resolution.

rundir:

The path to the run directory.