EPA Releases Updated Air Model to Advance Gold Standard Science and Cooperative Federalism

EPA Releases Updated Air Model to Advance Gold Standard Science and Cooperative Federalism

October 19, 2026

WASHINGTON - Today, U.S. Environmental Protection Agency (EPA) released a major update to the Community Multi-scale Air Quality (CMAQ) model version 6.0, which provides the precise data state, local, and Tribal air agencies need to develop effective State Implementation Plans (SIPs) and meet National Ambient Air Quality Standards (NAAQS). The new update will give EPA's partner air agencies a more accurate and user-friendly platform that will allow for enhanced modeling capabilities for ozone, particulate matter, and other air emissions. The release marks a major milestone in the agency's renewed commitment to promoting cooperative federalism and advancing gold standard science to protect human health and the environment.

"By putting CMAQ version 6.0 into the hands of our state, local, and tribal partners, we are directly strengthening cooperative federalism," said Acting Assistant Administrator for Air and Radiation Abigale Tardif. "Environmental protection is a shared responsibility. This tool empowers regional authorities with gold standard science, ensuring they have the cutting-edge capabilities needed to make informed, localized decisions that protect their communities and comply with Clean Air Act requirements."

Key updates in CMAQ version 6.0 include:

• Upgraded Chemical Mechanisms: Improved simulations of ozone and secondary organic aerosol (SOA) formation.
• Global-to-Local Scaling: Improved integration of global-scale simulations to fine neighborhood-scale resolutions.
• Enhanced Source/Region Tracking Extensions: Upgrades to tools that give policy managers insights to the source categories and regions that may be contributing most to downwind pollutant impacts.
• Optimized Computational Efficiency: Faster processing times to help agencies save resources.

In addition to supporting regulatory bodies, this publicly available resource reinforces EPA's strong partnership with the academic community. Researchers and atmospheric scientists worldwide can leverage the updated framework to drive further innovations in air quality science.

To download CMAQ version 6.0 or access the updated technical documentation and user guides, visit the official EPA Photochemical Air Quality Modeling page.