Atmospheric Modeling and Analysis

CMAQ is an air quality model and software suite designed to model multiple pollutants at multiple scales. CMAQ allows regulatory agencies and state governments to evaluate the impact of air quality management decisions, and gives scientists the ability to probe, simulate, and understand chemical and physical interactions in the atmosphere.

The latest CMAQ software can be downloaded from the Community Modeling and Analysis Systems website .

Information about older versions and release notes are available from the "Release Notes" link on the right side of this page. CMAQv5.0 is currently undergoing final testing at EPA and the CMAS Center. CMAS will be releasing the model in the next few weeks and will send out notification on its availability. Information on updates and features in CMAQv5.0 and initial evaluation of the model will be presented at the 2011 CMAS Conference .

CMAQ 5.0 uses up-to-the minute data in its meteorology and chemical transport models. Additionally, instead of running models in sequence as it did previously, the meteorology and air chemistry models in CMAQ 5.0 interact on the fly in feedback loops to provide more accurate forecasts that reflect interactions between pollution and weather.

CMAQ 5.0’s new modeling framework will allow scientists to look at smaller, finer-resolution settings, such as individual towns and cities, and also to expand the model’s spatial scale to include the entire northern hemisphere.

Earlier versions of CMAQ have been used extensively in states’ National Ambient Air Quality Standards implementation plans, and by the National Weather Service to produce daily air quality forecasts for the nation.

Tutorial and Training course information for Model-3/CMAQ and related products can also be found on the CMAS website.