Single Domain Case - Geogrid

Setup the Model domain (geogrid.exe)

Ensure that that you have the terrestrial data somewhere on your computer
 

1. Ensure you are in the WPS/ directory

2. Edit namelist.wps
    Make the following changes:
    Note 1: As we are only interested in domain 1, you can ignore all values in the second column
    Note 2 : For detailed explanations of these variables, as well as suggestions for best practices, see the Best Practices WPS Namelist page, or Chapter 3 of the WRF User's Guide

max_dom = 1 
parent_id = 1,
parent_grid_ratio = 1,
i_parent_start = 1,
j_parent_start = 1,
e_we = 91,
e_sn = 100,
geog_data_res = 'default',
dx = 27000,
dy = 27000,
map_proj = 'mercator',
ref_lat = 28.00,
ref_lon = -75.00,
truelat1 = 30.0,
truelat2 = 60.0,
stand_lon = -75.0,
geog_data_path = 'Your WPS_GEOG data location'

4. Before running geogrid.exe, let's make sure the domain is in the right location

ncl util/plotgrids.ncl

    You should see the following domain:

    
 

4. Now run geogrid.exe to create static data for this domain:
    Note: This will overwrite any geo_em.d01.nc files you may have from previous runs,
    so save your old files somewhere else if you would like to keep them.

./geogrid.exe

The text below should appear on your screen during run time. Look for "Successful completion of geogrid" at the end of the run, indicating that all when well during the execution. A geogrid.log file containing more information will also be created. You can use this log file for troubleshooting purposes if you run into any problems.

Parsed 20 entries in GEOGRID.TBL
Processing domain 1 of 1
Processing XLAT and XLONG
Processing MAPFAC
Processing F and E
Processing ROTANG
Processing LANDUSEF
Calculating landmask from LANDUSEF ( WATER = 16 )
Processing HGT_M
Processing SOILTEMP
Processing SOILCTOP
Processing SCT_DOM
Processing SOILCBOT
Processing SCB_DOM
Processing ALBEDO12M
Processing GREENFRAC
Processing SNOALB
Processing SLOPECAT
Processing SLOPECAT
Processing CON
Processing VAR
Processing OA1
Processing OA2
Processing OA3
Processing OA4
Processing OL1
Processing OL2
Processing OL3
Processing OL4
Processing VAR_SSO
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! Successful completion of geogrid.         !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Make sure that the static file has been created:

geo_em.d01.nc
 

5. Check the contents of this file:

a. Use the ncdump utility:
    ncdump -h geo_em.d01.nc
b. Use the ncview utility.
c. This file can also be viewed with any of the supported graphical tools.

 

Below is the output file generated by this step. You can use this file if, for some reason, you aren't able to run geogrid successfully and you cannot get past the error: geo_em.d01.nc

Now interpolate our input data onto this domain