The behavior of PB2NC is controlled by the contents of the configuration file passed to it on the command line. The default PB2NC configuration may be found in the met-8.0/share/met/config/PB2NCConfig_default file. Additional information about configuration files can be found in $MET_BASE/config/README file. The configuration used by the test script may be found in the met-8.0/scripts/config/PB2NCConfig_G212 file. Prior to modifying the configuration file, users are advised to make a copy of the default:
Open up the $MET_TUTORIAL_DATA/config/PB2NCConfig_tutorial file for editing with your preferred text editor.
The configurable items for PB2NC are used to filter out the PrepBufr observations that should be retained or derived. You may find a complete description of the configurable items in the MET Users Guide or in the $MET_BASE/config/README file. Please take some time to review them.
For this tutorial, edit the $MET_TUTORIAL_DATA/config/PB2NCConfig_tutorial file as follows:
- Set message_type = [ "ADPUPA", "ADPSFC" ]; to retain only those 2 message types.
- In obs_window, set beg = -1800; and end = 1800; so that only observations within 30 minutes (1800 seconds) of the reference time will be retained.
- In mask, set grid = "G212"; to retain only those observations residing within the bounds of NCEP Grid 212 (on which the forecast data resides).
- Set obs_bufr_var = [ "QOB", "TOB", "ZOB", "UOB", "VOB", "D_WIND", "D_RH" ]; to retain observations for specific humidity, temperature, the u-component of wind, and the v-component of wind and to derive observation values for wind speed and relative humidity. This configuration replaces obs_grib_code. A list of valid GRIB codes, their units, and the corresponding abbreviations may be found here.
Save and close this file.