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Community Multiscale Air Quality Modeling System (CMAQ)

CMAQ Documentation

CMAQ can be customized to fit your research needs. Below are several types of CMAQ documentation designed for both new and veteran users of CMAQ. 


Release Notes 

Release notes for each CMAQ version are provided to outline the specific changes that were made to the modeling system since the previous release.  Click on the links below to view the selected version's release notes.

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CMAQ User's Guide

A comprehensive set of instructions for model users that covers:

  • Overview of science in the CMAQ modeling system
  • System requirements and installation
  • Required libraries
  • Description of CMAQ programs, input and output files
  • Directions for defining grids, layers, domains and chemistry
  • Directions for developing new CMAQ simulations and source code
  • Analysis tools for CMAQ
  • Table of CMAQ species names
  • Glossary

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Tutorials for Common Tasks 

Step-by-step directions to help you get started with various tasks within the CMAQ system including:

  • How to get started: Preparing your Linux system for installing and running CMAQ
  • How to run the CMAQ test case
  • How to create an ocean file
  • How to add chemically inert tracers to the CMAQ model
  • Understanding CMAQ program relationships: A flow diagram showing the dependencies between the different CMAQ programs

View CMAQ tutorials.Exit

We hope to add more tutorials over time.  We welcome suggestions for new tutorials for specific tasks.  Click on the "Contact Us" link at the top or bottom of the page to submit your idea. 

CMAQ Science Document

The original CMAQ Science Document (dated March 1999) contains chapters that address specific scientific and technical issues involved in the development and application of the CMAQ system. Collectively, it provides the scientific basis and point of reference for the state of the science captured in the June 1998 initial release of CMAQ. 

View the documentation for CMAQ's original science alrgorithms. Exit

Spatial Data Projection and Processing 

Information on how to create consistent geospatial data for CMAQ inputs using the Spatial Allocator (SA) utility.

Parallel Implementation of CMAQ

An introduction to how data-parallelism can be applied in the CMAQ system to increase computational efficiency. 

Read more about parallel implementation of CMAQ.

Configuring Weather Research and Forecasting Model (WRF) for Use with Air Quality Models 

  • Section from WRF3.7 Technical Documentation related to air quality modeling Exit- Description and procedures for using the Pleim-Xiu LSM, ACM2 PBL and Pleim Surface Layer Scheme in WRF including best practices and namelist options.
  • How to Run WRF with lighting assimilation:
    • User's Guide
    • WRF Lightning Assimilation Code(9 pp, 223 K) - Registry and FORTRAN files with the updates needed to run WRF with lightning assimilation.  Also a generic Python script to grid lightning data to your WRF domain.
    • Reference: Heath, N. K., J. E. Pleim, R. C. Gilliam, and D. Kang (2016), A simple lightning assimilation technique for improving retrospective WRF simulations, J. Adv. Model. Earth Syst., 8, 1806 – 1824, doi: 10.1002/2016MS000735Exit