Case 1: Single observation test with GLOBAL BE
Case 1: Single observation test with GLOBAL BE cindyhg Mon, 07/15/2019 - 14:38ARW SINGLE OBSERVATION TEST W/ GLOBAL BE
Introduction
This exercise consists of running the GSI analysis with a single pseudo observation at a specified location, to illustrate how that observation influences the analysis.
Further information on setting up a single observation test is available in section 4.2 of the GSI User's Guide.
The ARW background field is provided in netcdf format, and the global BE is employed as the background error covariance.
Setting up the Run Script
Setting up the Run Script cindyhg Mon, 07/15/2019 - 14:40ARW SINGLE OBSERVATION TEST W/ GLOBAL BE
Setting up the Run Script
For this exercise, make a copy of the prepared basic run script from the section Prepare run script for basic cases:
cp run_gsi_regional.ksh run_gsi_regional.ksh_psot
.Make the following additional modifications to the script
run_gsi_regional.ksh_psot
:
- Set the name/path for the analysis run directory
- Set up the one observation test option to true
if_oneob=Yes
- Select the background field format
bk_core=ARW
- Select the global background error covariance
bkcv_option=GLOBAL
An example of this run script is available from the link run_gsi_regional.ksh
Check the GSI namelist
Users can check the namelist to see how to set up a single observation test. The related namelist options include :
oneobtest=.true.
- Set the location of the pseudo observation:
&SINGLEOB_TEST
maginnov=1.0,magoberr=0.8,oneob_type='t',
oblat=38.,oblon=279.,obpres=500.,obdattim=${ANAL_TIME},
obhourset=0.,
/
An example namelist is available here.
Running the Script
Running the Script cindyhg Mon, 07/15/2019 - 14:40ARW SINGLE OBSERVATION TEST W/ GLOBAL BE
Running the Script
In this example, GSI is run as a 4-core MPI job. If you named your run script
run_gsi_regional.ksh_psot
and run on PBS system (Cheyenne), type:
qsub run_gsi_regional.ksh_psot
to launch the job. The progress of the job can be monitored by examining the tail of the standard out file in the run directory as set in the variable
WORK_ROOT
:
tail stdout
When completed,the contents of this run directory are provided in the following list .