Last week, the American Lung Association released a report about the state of the nation's air. In this region, ground-level ozone — also known as smog — remains a stubborn problem.
Many areas see levels that exceed federal health standards, and experts said they are concerned that climate change will make things worse.
Today, scientists released the results of a study predicting just how much -- a 70 percent increase in unhealthy summertime ozone levels by 2050, say researchers at the National Center for Atmospheric Research in Colorado.
Ozone is formed when sunlight and heat react with some of the gases from fossil fuel combustion.
Ozone literally sears the lungs. It can worsen the symptoms for people with asthma and other lung diseases, and even lead to premature death. Even for healthy people, it can cause coughing and throat irritation.
This region fails to meet federal health standards at least some of the time during the warmer months.
But the warmer temperatures predicted to come with climate change, plus higher atmospheric levels of methane that would also spur chemical reactions leading to ozone, we could have higher levels more often.
The researchers found that, by 2050, areas like this that already exceed levels could face unhealthy air during much of the summer.
"It doesn't matter where you are in the United States-climate change has the potential to make your air worse," said NCAR scientist Gabriele Pfister, the lead author of the new study, in a press release.
"A warming planet doesn't just mean rising temperatures, it also means risking more summertime pollution and the health impacts that come with it."
In a different scenario, Pfister and her colleagues found that sharp reductions in nitrogen oxides and volatile organic compounds — both of which lead to ozone formation — could reduce ozone pollution even as the climate warms, the press release said.