Community Modeling and Analysis System
CMAS Community Modeling and Analysis System
Upcoming Training
- CMAQ Online Training: Apr 08, 2025
- SMOKE Online Training: Apr 01, 2025
CMAS Conference
23rd Annual CMAS Conference, October 21-23, 2024Latest Releases
- CMAQ 5.5 (10/2024)
- VERDI 2.1.6 (10/2024)
- SMOKE v5.1 (07/2024)
- VERDI 2.1.5 (01/2024)
- All releases
Help
If you need help compiling or running one of our supported products, try the following:
Step 1 Read Model Documentation
Step 2 Search the CMAS Forum
Step 3 Take a Training
News
CMAQ 2024 User Survey
Greetings CMAS Community!
Following the release of CMAQv5.5, EPA is now in the development cycle for the next major release, planned for 2026. Input from the CMAQ user community can influence development priorities and improve the resources that EPA offers.
We invite you to fill out the CMAQ 2024 User Survey facilitated by the CMAS Center.
We appreciate your feedback and will carefully consider your comments. Thank you for your time and for your continued support!
https://unc.az1.qualtrics.com/jfe/form/SV_08mbELpkjwq8fNY
The survey will remain live until November 8th. We will share results of the survey on our website and at CMAS 2025.
You can view past survey results and how they were incorporated into CMAQ releases and resources here: CMAQ Community Survey Results | US EPA
Announcing the release of CMAQ version 5.5 (October 2, 2024)
The U.S. EPA Office of Research and Development and the Community Modeling and Analysis System Center are pleased to announce the release of CMAQ version 5.5.
What's new in CMAQv5.5?
- Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM) version 2 including updated formaldehyde chemistry impacting ozone and secondary organic aerosol formation
- New support for running pre-configured global CMAQ simulations coupled with meteorology from the Model for Prediction Across Scales - Atmosphere (MPAS-A)
- Expanded capabilities of the Integrated Source Apportionment Method (ISAM) to quantify source contributions to total secondary organic aerosol (SOA) and individual species
- Updates to ISAM source attribution estimates, mainly impacting coarse particles and secondary organic aerosols formed through cloud processes
- Updates to the Decoupled Direct Method (DDM) to improve second order ozone sensitivities
- Updated chemistry to properly capture photolysis effects from sub-grid clouds
- Revised algorithms for modeling dry deposition (M3DRY and STAGE updates)
- Improved accuracy and error checking for BDSNP soil NO in the MEGAN biogenic emissions algorithm
- MCIP (meteorology preprocessor) updates to grid origin definition for fine scale Lambert Conformal Grids (i.e., < 4km )
- Updates to Sulfur Tracking Model (STM) to properly attribute sulfate from gas phase chemistry
- Updates to the Explicit and Lumped Model Output (ELMO) synthesizer to fix erroneous output for several PM aggregates including PMF_OC, PMF_NCOM, TNO3
- New shp2cmaq python tool to convert GIS shapefiles into gridded netCDF mask files that can be used for defining regions and region families with DESID and using geographic source regions when running CMAQ-ISAM
- Simplified workflows for easier CMAQ installation
See the full list of CMAQv5.5 updates on our new CMAQ Wiki page: https://github.com/USEPA/CMAQ/wiki/CMAQv5.5-Series-FAQ
Download the source code and scripts, and access all documentation for this release from the USEPA GitHub repository: https://github.com/USEPA/CMAQ
Two-day test data for CMAQ version 5.5 are available from the CMAS Data Warehouse: https://www.epa.gov/cmaq/cmaq-inputs-and-test-case-data
Documentation for this release includes the following:
- Frequently asked questions for upgrading to version 5.5
- New and updated step-by-step tutorials for different features and functions of the software including tutorials for running CMAQ using chemical mechanism CRACMM2
- Release notes providing details on major changes and new features
- Tables of model species and chemical reactions in each chemical mechanism available in v5.5
CMAQ version 5.5 documentation direct link on GitHub: https://github.com/USEPA/CMAQ/blob/main/DOCS/README.md
Please report any bugs or problems with this release to the CMAS User Forum: https://forum.cmascenter.org
Additional user support, including training courses and other CMAS-supported software products is available through the CMAS Center website: www.cmascenter.org
Information for New Users
Welcome to CMAS! We are a community of environmental and air quality modelers. If you are interested in downloading CMAQ, SMOKE, BenMAP, or any of our other supported models, if you are looking for assistance with any of our supported models, if you are looking for a bibliography of air quality modeling related published works, or you are looking for an atmospheric modeling position, you've come to the right place!
The first thing you should do is create a CMAS user account. This will allow you full access to everything the site has to offer, including model downloads. Once you have a CMAS account, registering for our annual CMAS Conference or model trainings is a snap. Even if you change your email or address, you can easily edit your contact information (once you are logged in). All of your registrations and payment information can be found in your User Details on the top menu.
You can always use our search bar at the top to search within our site. You can always reach a CMAS team member with general CMAS-related questions (please no technical questions) by emailing cmas@unc.edu. And don't forget to read the latest issue of the CMAS Newsletter!
Supported Products
BenMAP is a Windows-based computer program that estimates the health benefits from improvements in air quality.
The Community Multiscale Air Quality (CMAQ) Modeling System combines current knowledge in atmospheric science and air quality modeling with multi-processor computing techniques in an open-source framework to deliver fast, technically sound estimates of ozone, particulates, toxics, and acid deposition.
CoST/EMF allows users to estimate the emission reductions and costs associated with future-year control scenarios, and then to generate emission inventories with the control scenarios applied.
C-TOOLS are a suite of web-based modeling and visualization tools for community scale modeling of local air quality.
The Fertilizer Emission Scenario Tool for CMAQ (FEST-C) system is used to simulate daily fertilizer application information using the Environmental Policy Integrated Climate (EPIC) model for a defined CMAQ domain.
The Input/Output Applications Programming Interface, otherwise known as the I/O API, is the standard data access library for EPA's Models-3 project. The I/O API provides a variety of data structure types for organizing data, and a set of access routines which offer selective direct access to data in terms meaningful to the modeler.
MCIP (Meteorology-Chemistry Interface Processor) is a processing program that takes in meteorological model outputs and prepares meteorological data needed by CMAQ.
The Research LINE-source dispersion model for near-surface releases (R-LINE) research grade dispersion model that is currently under development by EPA ORD for near-roadway assessments. R-LINE is a part of EPA ORD's ongoing evaluation of air quality impacts in the near-road environment. The research model is based upon a steady-state Gaussian formulation and is designed to simulate line type source emissions (e.g. mobile sources along roadways) by numerically integrating point source emissions.
The Sparse Matrix Operator Kernel Emissions (SMOKE) Modeling System allows emissions data processing methods to integrate high-performance-computing (HPC) sparse-matrix algorithms. The SMOKE system is a significant addition to the available resources for decision-making about emissions controls for both urban and regional applications. It provides a mechanism for preparing specialized inputs for air quality modeling research, and it makes air quality forecasting possible.
A collection of tools designed to create spatial surrogates for meteorological and air quality modeling without using GIS software.
VERDI is a Java program for visualizing meteorology, emissions, and air quality modeling data. With options for overlaying GIS Shapefiles and observational data onto model output, VERDI offers a range of options for viewing atmospheric modeling data. VERDI scripting provides a powerful interface for automating the production of graphics for analyzing your data.
Community Modeling and Analysis System (CMAS)
General inquiries about the CMAS Center and questions about the web site should be directed to cmas@unc.edu
