Getting an Upgrade to Protect Air Quality


EPA scientist Havala Pye uses CMAQ to show emissions related to vegetation in the Southeast United States.

By Dina Abdulhadi

What technology upgrades matter to you? Most people I know get excited about their new phones: faster speeds, better cameras, and new traffic apps, to name a few.

You know that camera on your old phone? The images were pixelated; if you zoomed in, you could not see the details of your dog’s whiskers or the horizon on a smoggy day. Just like your new phone with a better camera, scientists have an upgrade to an important tool used to visualize the earth’s atmosphere.

With this major upgrade to an atmospheric model – the Community Multi-scale Air Quality model (CMAQv5.1) – researchers and air quality managers have improved options to understand how air pollution moves throughout the atmosphere locally, nationally, and globally. The upgrade provides air quality managers an even more powerful tool to evaluate air quality and protect the air we breathe.

For example, one new option is like the zoom feature on a cell phone camera. “Zooming out,” researchers can see how multiple air pollutants—including ozone, particulate matter (PM), and several air toxics—move across the Northern Hemisphere. This expanded scale helps to see what actions can be taken locally or nationally to improve air quality.  Researchers can also “zoom in” using the model to the city or neighborhood scale, where CMAQ can help identify pockets prone to higher air pollution. Modeling pollution at this smaller scale allows researchers to estimate pollution exposures more accurately, which can be used to determine air pollution risks to health.

While people are not standing in long lines outside of a retail store for this latest version, the model is used worldwide to conduct air quality research and to make decisions on how best to protect air quality.

CMAQ was first launched 15 years ago, and since then, air quality has improved with the use of this and other tools. More recently, CMAQ was used to determine the impact of EPA’s new standards for car emissions and fuels. The standards aim to reduce sulfur in gasoline by 60 percent starting in 2017, helping avoid up to 2,000 premature deaths per year and 50,000 cases of respiratory ailments in children.

Researchers are using the model to learn more about what air pollution can do to our health. By using CMAQ to estimate ozone levels across North Carolina, for example, researchers found that ozone concentrations may be linked with an increased risk of lower birthweights in rural and urban areas. By estimating the levels of PM and ozone exposures over time for farmers in North Carolina and Iowa, researchers also found a potential elevated risk of Parkinson’s disease.

Science and technology constantly advances, and in turn it changes how we think about the world and our environment. Powerful tools like CMAQv5.1 are making a big difference in protecting public health and the environment and will continue to evolve, much like the technology we use every day to connect with friends and family, find out if it will rain, and even get a daily forecast of air quality using the Air Quality Index.


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About the author: Dina Abdulhadi works with the science communication team in EPA’s Office of Research and Development.

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