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  2. Community Multiscale Air Quality Modeling System (CMAQ)
  3. Learn About CMAQ

Browse CMAQ Applications

The CMAQ system has been used to address major environmental issues. Click on a category below to learn about the different ways the CMAQ model is applied to help communities, states and countries improve human health and the environment on global to local scales.    


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EPA Mission Support

Models are widely used to identify sources of air quality problems and to assist in the design of effective strategies to reduce pollutants. Read more about how CMAQ informs federal and state actions:

  • CMAQ's Support of EPA's Mission

Evaluation Studies

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Evaluation of the CMAQ system has been designed to characterize how model predictions compare to observations, as well as identify what model improvements are needed in future versions of the modeling system. The following are some recent evaluation studies of the CMAQ system: 

  • Model Evaluation Framework
  • Incremental Evaluation of New CMAQ Versions
  • Improving PM2.5 chemistry in CMAQ
  • Air Quality Model Evaluation International Initiative (AQMEII)
  • Dynamic Evaluation and Trend Analysis
  • Evaluation of CMAQ Applications at Neighborhood Scales

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Human Exposure to Pollutants

People are exposed to a number of environmental pollutants as a result of different sources including wildfires, combustion, and agriculture. Learn about how CMAQ model predictions inform human health exposure estimates:

  • Modeling Toxic Air Pollutants
  • Nitrate in Groundwater
  • Air Quality and Climate
  • Trends in Air Pollution Exposure
  • Projecting Changes to Human Health

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Ecosystems and Air Quality

Ecosystem exposure to atmospheric pollutants influences the flow of benefits from nature to people. Listed below are a few examples of how CMAQ is used to predict the exposure of plants, animals, soil, and water to pollutants:

  • Chesapeake Bay
  • Atmospheric Deposition
  • Watershed Acidification
  • Gulf of America Hypoxia

Stock photo of a wildfire - modeling emissions from wildland fires is an area of ongoing research in CMAQ

Emerging Applications

As a deterministic model, the CMAQ model lends itself to novel applications.  Learn more about emerging applications of the CMAQ model below:

  • Volatile Chemical Products (VCPs)
  • PFAS Fate and Transport
  • Wildland Fires
  • Hemispheric Scales
  • Windblown Dust

Community Multiscale Air Quality Modeling System (CMAQ)

  • Learn About CMAQ
    • CMAQ's Purpose
    • CMAQ 25th Anniversary
    • Overview of Science Processes
    • Browse CMAQ Applications
  • CMAQ Models
    • CMAQ-ISAM
    • CMAQ-DDM-3D
    • WRF-CMAQ
    • MPAS-CMAQ
  • Download CMAQ
    • Model Source Code
    • Documentation
    • Resources/Utilities for Model Users
  • CMAQ Research
    • Research Highlights
    • CRACMM
    • How to Cite CMAQ
    • Publications and Peer Review
  • CMAQ Community
    • CMAQ User Community
    • Opportunities for Collaboration
    • CMAQ Webinars
    • CMAQ Community Survey Results
  • Download Data
    • Download CMAQ data
    • Test Cases
    • EPA'S Air Quality Time Series (EQUATES) Project
  • About Us
  • Frequent Questions
Contact Us about the Community Multiscale Air Quality Modeling System
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 4, 2025
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