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CMAQ: The Community Multiscale Air Quality Modeling System

  • New CMAQv5.5 Release!

    • Learn about new features in our latest release
  • A New Aerosol Dry Deposition Model for Air Quality and Climate Modeling

    • Learn more about how advanced measurement techniques have lead to improvements in CMAQ's M3DRY dry deposition module.

  • Cloud-based data sharing and CMAQ modeling

    • Learn about running CMAQ on a cloud environment
    • Access a full set of CMAQ-ready inputs on the cloud
    • Access 3D CMAQ output on the cloud
  • Impact of Aerosol Nitrate Photolysis on air quality

    • Photolysis of aerosol nitrate creates tropospheric ozone.

    • Learn more about a chemical pathway that prolongs the lifetime of nitrogen oxides.

CMAQ (see-mak): an active open-source development project of the U.S. EPA that consists of a suite of programs for conducting air quality model simulations. CMAQ combines current knowledge in atmospheric science and air quality modeling, multi-processor computing techniques, and an open-source framework to deliver fast, technically sound estimates of ozone, particulates, toxics and acid deposition.

Learn about CMAQ

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  • CMAQ's Purpose
  • CMAQ 25th Anniversary
  • Overview of Science Processes
  • CMAQ Applications

CMAQ Models

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  • CMAQ-ISAM
  • CMAQ-DDM-3D
  • WRF-CMAQ
  • MPAS-CMAQ

Download CMAQ

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CMAQ Research

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  • Research Highlights
  • Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM)
  • How to Cite CMAQ
  • Publications and Peer Review

CMAQ Community

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  • CMAQ User Community
  • Opportunities for Collaboration
  • CMAQ Webinars
  • CMAQ Community Survey Results

Download Data

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  • Download CMAQ Data
  • Model Inputs and Test Case Data
  • EPA's Air Quality Time Series (EQUATES) Project 
Frequent Questions about CMAQ
Contact Us about the Community Multiscale Air Quality Modeling System to ask a question, provide feedback, or report a problem.
Last updated on December 30, 2024
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