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Contact Us

CMAQ: The Community Multiscale Air Quality Modeling System

  • Expanded analysis capabilities with AMETv1.5

    • The Atmospheric Model Evaluation Tool (AMET) is a suite of software for evaluation of meteorological and air quality models. 

    • Version 1.5 includes: 
      • New evaluation plots and plotting options
      • New evaluation options for real or near-real-time modeling
      • Streamlined batch and wrapper scripts for creating many plots at once
  • CMAQ SOA used to inform cardiorespiratory mortality analysis

    • Learn more about a new study in Nature Communications
  • Explore global-to-local chemical transport modeling

    • The Advanced Air Quality Modeling System (AAQMS) is used to simulate influences of global emissions and meteorology on regional and local air quality. 
    • Learn more about a new study in JGR Atmospheres 
  • Latest Release: CMAQv5.3.3

    • Learn about new features in our latest release
    • CMAQ source code and User's Guide available on GitHub
    • Watch the CMAQv5.3 webinar on Enhanced Capabilities to Analyze Emissions Scenarios

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 Models
  • Overview of Science Processes
  • Publications and Peer Review
  • CMAQ Fact Sheets
  • CMAQ Impact Statement

CMAQ Applications

Forest fire
  • EPA Mission Support
  • Evaluation Studies
  • Human Exposure to Pollutants
  • Ecosystems and Air Quality
  • Emerging Applications

Download CMAQ

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  • Model Source Code
  • Documentation
  • Model Inputs and Test Case Data
  • Resources/Utilities for Model Users

CMAQ Research

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  • Research Highlights
  • How to Cite CMAQ
  • Opportunities for Collaboration
  • CMAQ Developers Guide

CMAQ Community

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  • CMAQ User Community
  • CMAQ Community Survey Results

CMAQ Data

Map of CMAQ output
  • About CMAQ Data 
  • EPA's Air Quality Time Series (EQUATES) Project 
  • Download CMAQ Data
Frequent Questions about CMAQ
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on August 2, 2022
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