WRF-Chem is the Weather Research and Forecasting (WRF) model coupled with Chemistry. The model simulates the emission, transport, mixing, and chemical transformation of trace gases and aerosols simultaneously with the meteorology. The model is used for investigation of regional-scale air quality, field program analysis, and cloud-scale interactions between clouds and chemistry.

The development of WRF-Chem is a collaborative effort among the community. NOAA/ESRL scientists are the leaders and caretakers of the code. The Official WRF-Chem web page is located at the NOAA web site. Our model development is closely linked with both NOAA/ESRL and DOE/PNNL efforts. Description of PNNL WRF-Chem model development is located at the PNNL web site as well as the PNNL Aerosol Modeling Testbed .

Use the MOZART Download page to retrieve MOZART-4 model results.

Information on running WRF-Chem with the MOZART chemical mechanism can be found in the MOZCART User's Guide.

Processors Available to the Community:

NEW (October 2013): Release of a new pre-processing tool. Anthro_emiss can be used to map from global anthropogenic emission inventories to WRF-Chem input files.


NCAR/ACD has developed a program to create time-varying chemical boundary conditions for WRF-Chem from MOZART-4 output. For questions about running mozbc please contact: Stacy Walters (stacy at ucar . edu), Mary Barth (barthm at ucar . edu), or Gabriele Pfister (pfister at ucar . edu). For technical details please refer to this document: Conversion of MOZART species to WRF-Chem. To obtain mozbc, see the Download section below.


Bio_emiss is a pre-processor for creating MEGAN input for WRF-Chem. To obtain bio_emiss, see the Download section below.

preprocessor tools

Pre-processor tools for running WRF-Chem / MOZCART. See the Download section below.


Fortran based preprocessor to create WRF-Chem ready anthropogenic emissions files (wrfchemi_<domain>_<date> or wrfchemi_{00z,12z}_<domain>) from global inventories on a lat/lon projection. Users are strongly advised to consult the README files before compiling and using the code. See the Download section below.


Use the Processors Download page to register and retrieve the above software packages.

Upper Boundary Conditions

Download input files for running WRF-Chem V3.3.1 with Chemical Upper Boundary Conditions: UBC_inputs.tar


Fortran based preprocessor for creating fire emission inputs for WRF-Chem when running with plumerise and also for creating fire emission inputs for the MOZART-4 and CAM-Chem global models. The fire emissions inventory is based on the Fire Inventory from NCAR (FINN). Both software (fire_emis.tgz) and required FINN input data sets are available at the download page.

The fire_emis.tgz file when uncompressed {tar -zxf fire_emis.tgz} yields three directories {data_files, src, and test} and two readme files {README.WRF.fire and README.GLB.fire }. The data_files directory is empty and is where users should put the FINN files and the wrfinput_d<domain> file(s). The test directory contains two test namelist input files, one for creating WRF inputs and another for creating global inputs. Users are highly advised to read the README files before using the fire emission utility.