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
- CMAQ user's guide
- Tutorials for common tasks
- CMAQ developers guide
- CMAQ Science Document
- EPA Regulatory Modeling Guidance
- How to cite CMAQ
- CMAQ publications
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. Beginning with CMAQv5.4, release notes are available on the CMAQ wiki. Release notes for prior versions are included in the DOCS folder of the code repository. Click on the links below to view the selected version's release notes.
- FAQ for upgrading to the latest CMAQ version
- Release Notes Wiki for CMAQv5.5 (current version) and CMAQv5.4
- CMAQv5.3, v5.3.1, v5.3.2, v5.3.3
- CMAQv5.2.1
- CMAQv5.2
- CMAQv5.2 DDM-3D
- CMAQv5.1
- CMAQv5.0.2
- CMAQv5.0.1
- CMAQv5.0
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
- Description of CMAQ programs, input and output files
- Directions for defining grids, layers, domains and chemistry
- Description of configuration options for CMAQ science options
- Directions for using CMAQ instrumented models
- Directions for customizing emissions processing
- Analysis tools for CMAQ
- Tips on creating CMAQ geospatial data inputs
- An introduction to the parallel implementation CMAQ for increased computational efficiency
- Tips on configuring the Weather Research and Forecasting Model (WRF) for use with air quality models
Read the CMAQ User's Guide online.
Read the tutorial on running the CMAQ benchmark case
Tutorials for Common Tasks
Step-by-step directions to help you get started with various tasks within the CMAQ system including:
- Scripts to install software needed to run CMAQ (New with v5.5 release!)
- How to run the CMAQ test case with the Community Regional Atmospheric Chemistry Multiphase Model (CRACMM) chemical mechanism (New with v5.5 release!)
- How to run the CMAQ CB6r5 test case (Updated for v5.5 release!)
- How to run the CMAQ-DDM-3D test case (Updated with v5.5 release!)
- How to run the CMAQ-ISAM test case (Updated for v5.5 release!)
- Building WRF-CMAQ for GNU
- How to modify a chemical mechanism in CMAQ
- How to build CMAQ using the GNU compiler
- How to build CMAQ using the Intel compiler
- How to debug issues issues encountered when installing and running the CMAQ test case.
- Getting started with the CRACMM chemical mechanism
- How to prescribe emissions using the DESID module
- How to create an ocean file
- How to add chemically inert tracers to the CMAQ model
- How to create Initial and Boundary Conditions files from seasonal average Hemispheric CMAQ output
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 Developers Guide
EPA welcomes submissions of new code to the CMAQ system from the user community. To facilitate the integration of new code into a future CMAQ public release, our team created the CMAQ Developers Guide. The Developers Guide describes general development practices within the CMAQ system and step-by-step instructions on how to contribute source code to the EPA CMAQ code repository hosted on GitHub. Prospective developers are asked to read the guide prior to starting a project within the CMAQ framework.
General guidelines for new code submissions include:
- Check that the code is consistent with the current model version.
- Use consistency in coding practices for any new code.
- Document all code testing activities including results showing:
- A benchmark case for the revised code (including documentation of input data, output data and runscripts).
- Impacts on computational time performance.
- Viability on different platform-compiler combinations (at least Intel, GNU and Portland Group Fortran).
- Document or provide references to the peer-reviewed literature supporting new science algorithms.
- Provide ongoing support and technical guidance for the use of the code updates.
The CMAQ Developers Guide is available through GitHub with the official release of CMAQ.
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 algorithms.
EPA SIP Modeling Guidance
The Air Quality Modeling Group within the Office of Air Quality Planning and Standards provides technical guidance to states on how to conduct modeling as part of State Implementation Plan (SIP) demonstrations for O3, PM2.5 and regional haze.
