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Managing Air Quality - Air Quality Modeling

Air quality modeling is a mathematical simulation of how air pollutants disperse and react in the atmosphere to affect ambient air quality.

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Modeling helps estimate the relationship between sources of pollution and their effects on ambient air quality. Air quality managers use models to identify source contributions to air quality problems and assist in the design of effective strategies to reduce harmful air pollutants.

Inputs for air quality models include meteorological data and source information like emission rates and stack height. These models are designed to characterize primary pollutants that are emitted directly into the atmosphere.  Some models also characterize secondary pollutants that are formed as a result of complex chemical reactions within the atmosphere.

How is Modeling Used?

In the United States, air quality managers use models to predict the impacts from potential new emission sources. Managers also apply models to simulate ambient pollution concentrations under different policy scenarios, as a tool to make and justify decisions. Models are also used to determine the relative contributions from different sources in tracking trends, monitoring compliance, and making policy decisions.

Additional Resources Related to Models Used by EPA