WRF ARW User's Guide - MMM - UCAR

WPS
geog_data_path variable. Also, the user may select which resolution of static data
geogrid will interpolate from using the geog_data_res variable, whose value should
match one of the resolutions of data in the GEOGRID.TBL. If the full set of static data
are downloaded from the WRF download page, possible resolutions include '30s', '2m',
'5m', and '10m', corresponding to 30-arc-second data, 2-, 5-, and 10-arc-minute data.
Depending on the value of the wrf_core namelist variable, the appropriate
GEOGRID.TBL file must be used with geogrid, since the grid staggerings that WPS
interpolates to differ between dynamical cores. For the ARW, the GEOGRID.TBL.ARW
file should be used, and for the NMM, the GEOGRID.TBL.NMM file should be used.
Selection of the appropriate GEOGRID.TBL is accomplished by linking the correct file
to GEOGRID.TBL in the geogrid directory (or in the directory specified by
opt_geogrid_tbl_path, if this variable is set in the namelist).
> ls geogrid/GEOGRID.TBL
lrwxrwxrwx 1 15 GEOGRID.TBL -> GEOGRID.TBL.ARW
For more details on the meaning and possible values for each variable, the user is referred
to a description of the namelist variables.
Having suitably defined the simulation coarse domain and nested domains in the
namelist.wps file, the geogrid.exe executable may be run to produce domain files. In the
case of ARW domains, the domain files are named geo_em.d0N.nc, where N is the
number of the nest defined in each file. When run for NMM domains, geogrid produces
the file geo_nmm.d01.nc for the coarse domain, and geo_nmm_nest.l0N.nc files for
each nesting level N. Also, note that the file suffix will vary depending on the
io_form_geogrid that is selected. To run geogrid, issue the following command:
> ./geogrid.exe
When geogrid.exe has finished running, the message
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! Successful completion of geogrid. !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
should be printed, and a listing of the WPS root directory (or the directory specified by
opt_output_from_geogrid_path, if this variable was set) should show the domain files.
If not, the geogrid.log file may be consulted in an attempt to determine the possible cause
of failure. For more information on checking the output of geogrid, the user is referred to
the section on checking WPS output.
> ls
drwxr-xr-x 2 4096 arch
-rwxr-xr-x 1 1672 clean
-rwxr-xr-x 1 3510 compile
-rw-r--r-- 1 85973 compile.output
-rwxr-xr-x 1 4257 configure
-rw-r--r-- 1 2486 configure.wps
-rw-r--r-- 1 1957004 geo_em.d01.nc
WRF-ARW V3: User’s Guide 3-13