diffwrf

Purpose

• List the contents of a WRF input, output, restart, or boundary datasets.
• Extract a field in wgrib text output format, also suitable for plotting using HMV.
• Compare two WRF datasets and generate field-by-field difference statistics.
• Supported formats include: NetCDF, Native binary, GRIB1 (use wgrib directly)

Necessary Software

NetCDF libraries needed for NetCDF version.

No additional libraries needed for native-binary version.

Distribution and compilation

diffwrf is distributed with WRF and built when WRF is configured and compiled.

• diffwrf for NetCDF is external/io_netcdf/diffwrf
• diffwrf for native binary I/O is external/io_int/diffwrf

Steps to Run Utility

• To list the fields of a dataset
  
  diffwrf filename list
  
  
• To extract all time frames of a field in ascii form and write to the file fort.88
  
  diffwrf filename fieldname [level]
  
  fieldname is the name of the field exactly as listed (case sensitive)
  
  level is an optional integer argument. If specified, only that level of a multi-level field will be output; otherwise, the entire field will be output
  
  Note that the resulting fort.88 output file may be plotted to a X-window display device using the HMV tool with the following command:
  
  hmv -3 fort.88
  
  
• To difference two wrf datasets
  
  diffwrf filename1 filename2
  
  For each field in each time frame stored in the files, diffwrf will display RMS, L2, and point-max differences. Note that the files must match in other respects; the sizes, number, types, and time stamps of the fields must be the same in each file.