Science Wednesday – Modeling Matters: See Mack Run the Half-Marathon

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By Tanya Otte

Lots of people like running. I’m not one of them…unless it involves running models! Since I was hired, I’ve been a part of a team that develops and runs models to help understand interactions between meteorology, natural and anthropogenic (“human-caused”) emissions, and air quality. The heartbeat of the air quality model development occurs in EPA’s Atmospheric Modeling and Analysis Division and with the Community Multiscale Air Quality Modeling (CMAQ) system, the Nation’s premier air quality simulation model.

CMAQ (pronounced “see mack”), a state-of-the-science tool for air quality modeling, was first publically released in 1998 by the EPA, and it now boasts a worldwide community of more than 3,700 users in 95 countries. CMAQ has been used by the EPA and by state environmental agencies to support air quality policy decisions. Nations around the world use CMAQ to study air pollution issues and create air quality management strategies. CMAQ provides daily ozone forecast guidance issued by the National Weather Service. The CMAQ user community spectrum spans academia, government, and private industry. CMAQ is one of the most widely respected modeling tools of its genre.

This month, EPA is releasing CMAQ 5.0. Major updates to CMAQ, like this, occur about every three years. CMAQ 5.0 incorporates the latest developments in air quality science, and it can be used to examine the interactions between air quality and climate. One of the biggest advances in CMAQ 5.0 is a comprehensive and synchronized coupling of meteorology and air chemistry to more accurately simulate the feedbacks between weather and air pollution.

This month, EPA also celebrates the 10th anniversary of its partnership with the Community Modeling and Analysis System (CMAS) Center. CMAS has been the conduit for public releases of CMAQ, and they have been instrumental in brokering international scientific contributions to CMAQ. CMAS has provided training and online support for the CMAQ community, and they host an annual workshop dedicated to exchanging the most updated scientific findings. This year’s workshop takes place October 24-26, and more than 250 participants have registered.

CMAQ just completed the half-marathon (measured in years, not miles). With a strong team at the EPA and a diverse and growing community of international collaborators, CMAQ will be running the race for many years to come!

About the author: Tanya Otte, a research physical scientist, has worked at EPA in atmospheric modeling and analysis since 1998.

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