WRF ARW User's Guide - MMM - UCAR

POST-PROCESSING
NCL
With the use of NCL Libraries (http://www.ncl.ucar.edu), WRF-ARW data can easily
be displayed.
The information on these pages has been put together to help users generate NCL scripts
to display their WRF-ARW model data.
Some example scripts are available online
(http://www.mmm.ucar.edu/wrf/OnLineTutorial/Graphics/NCL/NCL_examples.htm), but
in order to fully utilize the functionality of the NCL Libraries, users should adapt these
for their own needs, or write their own scripts.
NCL can process WRF ARW static, input and output files, as well as WRF-Var output
data. Both single and double precision data can be processed.
WRF and NCL
In July 2007, the WRF-NCL processing scripts have been incorporated into the NCL
Libraries, thus only the NCL Libraries, are now needed.
Major WRF ARW related upgrades have recently been added to the NCL libraries.
In order to use many of the functions, NCL version 5.1.0 or higher is required.
Special functions are provided to simplify the plotting of WRF ARW data.
These functions are located in
"$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl".
Special NCL built-in functions have been added to the NCL libraries to help users
calculate basic diagnostics for WRF ARW data.
All the FORTRAN subroutines used for diagnostics and interpolation (previously
located in wrf_user_fortran_util_0.f) has been re-coded into NCL in-line functions. This
means users no longer need to compile these routines.
What is NCL
The NCAR Command Language (NCL) is a free interpreted language designed
specifically for scientific data processing and visualization. NCL has robust file input and
output. It can read in netCDF, HDF4, HDF4-EOS, GRIB, binary and ASCII data. The
graphics are world class and highly customizable.
WRF-ARW V3: User’s Guide 9-2