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Community Multiscale Air Quality Modeling System (CMAQ)

Browse CMAQ Applications

Exploring Air Pollution from Global Scales to Local Impacts

The CMAQ system has been used to address major environmental issues. Click on the map  below to learn about how the CMAQ model provides information to help communities, states and countries improve human health and the environment on global to local scales.

Source: Leaflet |Tiles © Esri

Click on a category below to learn more about the different ways the CMAQ model is applied.


Stock photo of the EPA headquarters in Washington DCEPA 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:

Evaluation Studies

Stock photo of a magnifying glass zooming in on a bar graph and line graph

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: 

Smog over Los Angeles at sunsetHuman 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:

Stock photo of ducklings swimming on a lakeEcosystems 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:

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

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