Global Grid-to-Grid (g2g) Retro Verification (against ECMWF analyses)

Updated: February 26, 2026

Step 1: Pull the relevant grids from the model output and analysis files¶

Copy /home/role.amb-verif/GSL_verif-global/xml/retro/gfs_g2g_init_ecmwf_retro_template.xml to a working directory of your choice.
Open it in vi or another editor.
String replace MODELNAME for your model name. In vi, this is done with :%s/MODELNAME/<your_model_name>/g
1. Note: you can verify more than one model in the same workflow. For an example of how this works, you can view (but please don’t edit!) /home/role.amb-verif/GSL_verif-global/xml/gfs_g2g_init_rt.xml.
Change the path on line 12 from “/PATH/TO/MODEL/DATA” to the actual path to your model output files.
1. If your model is a standard MPAS setup, your path should point to the directory that has all of the dated output directories in it. For example, the correct path for the MPAS_global_uniform on Jet is /home/role.wrfruc/mpas_global_uniform.
2. If your model grib2 files are in a format like “2203418000012”, your path should point to the directory that contains those grib2 files.
3. If your model grib2 files are in a format like gfs.t00z.pgrb2.0p25.f090, your path should point to the root directory for your model cycles, which contains sub-directories such as gfs.20220111, gfs.20220112, etc. For example, the correct path for the FV3_GSL_L127_dev1 on hera would be /home/rtfim/UFS-CAMsuite_dev1/FV3GFSrun/rt_ufscam_l127_dev1.
Change the path on line 16 from /PATH/TO/ANL/DATA to the actual path to your ECMWF analysis files.
1. The path should be to the directory that contains the ECMWF oper and scda subdirectories.
On line 69, set the date strings for your start and end dates. These should be in the format YYYYMMDDHHMM.
On line 83, if your model is a standard MPAS setup, change “GFS_init_with_calc.py” to be “MPAS_init_with_calc.py”. If your model grib2 files are in a format like “2203418000012”, leave that line as-is. If they are in a format like gfs.t00z.pgrb2.0p25.f090, and the path to the output includes “/products/atmos/grib2/0p25/”, change “GFS_init_with_calc.py” to be “GFS_GSL_init_with_calc_new_dirs.py”. Otherwise if the path just contains “/atmos/”, use “GFS_GSL_init_with_calc.py”.
Submit and run the workflow in rocoto. Upon completion, you should have new pre-processed grib2 files in /home/role.amb-verif/GSL_verif-global/verif/g2g_retro/MODELNAME/realtime and /home/role.amb-verif/GSL_verif-global/verif/g2g_retro/ECMWF_anl/realtime

Step 2: Run the METplus verification to generate statistics¶

Copy /home/role.amb-verif/GSL_verif-global/xml/retro/metplus_ecmwf_g2g_retro_template.xml to a working directory of your choice.
Open it in vi or another editor.
String replace MODELNAME for your model name. In vi, this is done with :%s/MODELNAME/<your_model_name>/g
1. As before, you can modify the workflow to verify more than one model at once. For an example of how this works, you can view (but please don’t edit!) /home/role.amb-verif/GSL_verif-global/xml/metplus_gfs_g2g.xml.
On line 71, set the date strings for your start and end dates. These should be in the format YYYYMMDDHHMM.
The templates are currently configured for a retro which has been initialized every 120 hours (5 days), for a 120hr cadence. You can modify this to whatever the initialization cadence is for your own model by changing the “120:00:00” on line 71 to reflect the desired cadence in hours, and then also updating the “120hr” string to your new cadence on lines 19 and 71.
On line 147, set the resolution of the region polygons that you wish to use. Current options are “0deg25” and “15km”. Your region polygons don’t need to be the same resolution as your model, although note that MPAS doesn’t seem to go all the way to the edge of the global domain (it stops at 89.1 degN instead of 90, for example), so for MPAS it is recommended that you use the 15 km regions.
Submit and run the workflow in rocoto. Upon completion, you should have new .stat files in /home/role.amb-verif/GSL_verif-global/verif/g2g_retro/MODELNAME/realtime/METplus
Repeat steps 1-5 for /home/role.amb-verif/GSL_verif-global/xml/retro/metplus_ecmwf_g2g_anom_retro_template.xml if you also want to calculate ACC.

Step 3: Load your stat files into the METexpress database¶

Copy /home/role.amb-verif/GSL_verif-global/xml/retro/mv_load_gsl_retro_g2g_template.xml to a working directory of your choice, and rename it something descriptive.
Change the database on line 9 from mv*gsl_global_g2g_retros to something to describe your work. For example, if this retro is part of a certain case study, the database name could be mv_your-name_case-study-name. YOUR DATABASE NAME MUST START WITH “mv*” OR METEXPRESS WILL IGNORE IT. You can use the same database for multiple retro loadings (and you should load all related retros into one database), but please don’t load data into other people’s databases without their permission!
On line 26, replace “/PATH/TO/STAT/FILES” with the absolute path to the top-level directory where your stat files exist.
Use lines 29-31 (you can add more or take some away if necessary) to denote subdirectories under your top level path. These subdirectories should contain the stat files.
On line 3, enter your email.
If this is your first time using the database on line 9 (i.e., neither you nor anyone else has ever loaded data to it before), you will need to initialize the database. To do this, enter the following on the command line as amb-verif (replacing <your_db_name> with the actual name of your database):
```
mysql --defaults-file=/home/role.amb-verif/GSL_verif-global/config/gsd_met_admin_my.cnf -e'create database <your_db_name>;'
mysql --defaults-file=/home/role.amb-verif/GSL_verif-global/config/gsd_met_admin_my.cnf <your_db_name> < /home/role.amb-verif/GSL_verif-global/config/mv_mysql.sql
```

Run the following commands:

conda activate avid_verify_py3

setenv PYTHONPATH '/home/role.amb-verif/GSL_verif-global/bin/METdataio-3.2.0/'

python /home/role.amb-verif/GSL_verif-global/bin/METdataio-3.2.0/METdbLoad/ush/
met_db_load.py <path to your XML load file>

Your data will appear in METexpress the following morning, when the metadata refreshes.
If you need to view your data sooner than this, email mats.gsl@noaa.gov.