Point-Stat Tool: Configure

The behavior of Point-Stat is controlled by the contents of the configuration file passed to it on the command line. The default Point-Stat configuration file may be found in the METv1.1/data/config/PointStatConfig_default file. The configuration used by the test script may be found in the METv1.1/scripts/config/PointStatConfig file. Prior to modifying the configuration file, users are advised to make a copy of the default:

cp data/config/PointStatConfig_default tutorial/config/PointStatConfig_tutorial

Open up the tutorial/config/PointStatConfig_tutorial file for editing with your preferred text editor.

The configurable items for Point-Stat are used to specify how the verification is to be performed. The configurable items include specifications for the following:

• The forecast fields to be verified at the specified vertical levels.
• The threshold values to be applied.
• The type of point observations to be matched to the forecasts.
• The areas over which to aggregate statistics - as predefined grids, configurable lat/lon polylines, or individual stations.
• The confidence interval methods to be used.
• The interpolation methods to be used.
• The types of verification methods to be used.

You may find a complete description of the configurable items in section 4.3.2 of the MET User's Guide or in the comments of the configuration file itself. Please take some time to review them.

For this tutorial, we'll configure Point-Stat to verify the model temperature at two vertical levels. However, Point-Stat may be configured to verify as many or as few model variables as you desire. Edit the tutorial/config/PointStatConfig_tutorial file as follows:

• Set vx_grib_code[] = [ "TMP/Z2", "TMP/P750-850" ]; to verify 2-meter temperature and temperature fields between 750hPa and 850hPa.
• Set thresholds[] = [ "gt278 gt283 gt288", "gt278" ]; to indicate the thresholds to be applied to the fields listed above (TMP is in Kelvin).
• Set message_type[] = [ "ADPUPA", "ADPSFC" ]; to verify using those 2 observation types.
• Set mask_grids[] = [ "G212" ]; to accumulate statistics over the NCEP Grid 212 region.
• Set mask_polys[] = [ "MET_BASE/data/poly/EAST.poly" ]; to also accumulate statistics over the Eastern United States as defined by the polyline specified.
• Set interp_width[] = [ 1, 5 ]; to indicate that the forecast values should be interpolated to the observation locations using the nearest neighbor method and by averaging the forecast values over the 5 by 5 box surrounding the observation location.
• Set output_flag[] = [ 0, 2, 0, 0, 0, 2, 2, 2, 0, 0, 0, 0 ]; to indicate that the contignecy table counts (CTC), contingecy table statistics (CTS), continuous statistics (CNT), and scalar partial sums (SL1L2) line types should be output.