Table 1
Short characteristics of polarimetric variables [2].
| POLARIMETRIC VARIABLE | DEFINITION | SHORT CHARACTERISTICS | APPLICATION |
|---|---|---|---|
| ZH Horizontal reflectivity | reflectivity in the horizontally polarized channel | Increases with horizontal particle dimension, number concentration, density and water content. | – |
| ZV Vertical reflectivity | reflectivity in the vertical polarized channel | Increases with vertical particle dimension, number concentration, density and water content. | – |
| ZDR Differential reflectivity | difference between ZH and ZV | Increases with density, flattening and water content and is proportional to the hydrometeor concentration. | hydrometeor classification, clutter detection |
| PHIDP Differential phase shift | cumulative phase shift between H and V polarized waves | Is a measure of the attenuation integrated along the path. | attenuation correction, precipitation estimation |
| RHOHV Correlation coefficient | correlation coefficient between ZH and ZV | Is a measure of the diversity of hydrometeors in the radar volume and the data quality. RHOHV is close to 1 for most hydrometeors and significantly less than 1 for non-meteorological scatters. | clutter detection, hydrometeor classification |
| KDP Specific differential phase | derivative of PHIDP | Increases with density, flattening and water content and is proportional to the hydrometeor concentration. | attenuation correction, precipitation estimation |
Table 2
Description of the parameter used in the configuration file.
| PARAMETER | DESCRIPTION | DATA FORMAT[RANGE IF NECESSARY] | DEFAULT VALUES(IF NECESSARY) |
|---|---|---|---|
| Read data | |||
| raw_data_directory | path to raw data | str | – |
| subfolder_structure_raw_data | regex format of subfolders in the raw data directory | str | Y/m/d/ |
| error_flist_directory | path to file list with faulty files | str | – |
| monthly_clutter_directory | path to monthly clutter maps | str | – |
| subfolder_structure_clutter_directory | date format of subfolders in the monthly clutter directory | str | Y/m/ |
| static_clutter_directory | path to the static clutter maps | str | – |
| static_cmap | complete file path to the selected clutter map | – | |
| Save data in output directory | |||
| output_directory_tar_gz_files | output directory for compressed raw data | str | – |
| output_path_processed_files | output directory for processed data | str | – |
| output_path_error_flist | output directory for file list with faulty files | str | – |
| Settings for processing data | |||
| radar_location_identifier | Abbreviation for location and type of weather radar | str | – |
| epsg_code | EPSG Code of the desired coordinate reference system | integer | 32633 |
| nb_pixels | Resolution in pixels of the georeferenced data | integer | 1400 |
| dimensions | dimension of the data, two or three dimensional | list | [“azimuth”,”range”,”time”] |
| scan_interval | scan interval of the weather radar in seconds | integer | 300 |
| re_index_parameters | Correction of the original azimuth angles | list [0–360°] | [0.25, 360, 0.5] |
| moments_in_processed_files | Moments which are to be stored in the processed data | list | [‘RATE’, ‘DBZH’, ‘VRAD’, ‘ZDR’, ‘KDP’, ‘PHIDP’, ‘RHOHV’, ‘WRADH’, ‘FUZZ’,’DBZH_no_clutter’, ‘DBZH_CORR’, ‘PREC_ZR’] |
Figure 1
Software architecture of WRalNfo.
Figure 2
Polarimetric variables of raw data.
Figure 3
Clutter map.
Table 3
Weights of the fuzzy echo classification procedure.
| POLARIMETRIC VARIABLE | WEIGHT |
|---|---|
| RHOHV | 0.4 |
| PHIDP | 0.1 |
| ZDR | 0.4 |
| VRAD | 0.1 |
| CMAP | 0.5 |
Figure 4
Comparison of the clutter map and results of the fuzzy echo classification.
Figure 5
Comparison of raw reflectivity and clutter corrected reflectivity.
Figure 6
Results of the processed phase PHIDP.
Figure 7
ZPHI based recalculated PHIDP, KDP and specific attenuation.
Figure 8
Reflectivity before and after attenuation correction.
Figure 9
Attenuation corrected reflectivity and estimated precipitation.
Figure 10
Georeferenced and gridded precipitation data with WRalNfo.
Figure 11
Flowchart of WRalNfo in operation mode.