CMAQ Documentation | US EPA
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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 i
ssues 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
View CMAQ tutorials.
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.
Read the CMAQ Developer's Guide online
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 O
, PM
2.5
and regional haze.
Modeling Guidance for Demonstrating Air Quality Goals for Ozone, PM2.5, and Regional Haze
Community Multiscale Air Quality Modeling System (CMAQ)
Contact Us about the Community Multiscale Air Quality Modeling System
Contact Us about the Community Multiscale Air Quality Modeling System
to ask a question, provide feedback, or report a problem.