San Diego skyline
The San Diego skyline from Harbor Island. Photo by Chris Jennewein

Seven California metropolitan areas, including San Diego, rank among the 10 worst nationally for ozone pollution, due to wildfires and climate change.

In its annual assessment, the American Lung Association reported Wednesday that the Los Angeles metro area had the worst ozone pollution in the nation, followed by Visalia in the Central Valley. San Diego ranked sixth on the list with an average of 45 high-ozone days a year.

California also dominated the list for year-round particle pollution, but San Diego didn’t make that ranking.

“The 20th annual ‘State of the Air’ report shows clear evidence of a disturbing trend in our air quality after years of making progress: In many areas of the United States, the air quality is worsening, at least in part because of wildfires and weather patterns fueled by climate change,” said American Lung Association President and CEO Harold Wimmer.

The report analyzed data from 2015 to 2017, a three-year period that was the hottest recorded in global history.

The report estimated that 43 percent of the American population lives in counties with unhealthy ozone and/or particle pollution. It also found that 141 million people were exposed to unhealthy air during the study period, up from 134 million in last year’s report and 125 million in 2017’s study.

Ozone pollution, informally known as smog, can cause shortness of breath, trigger coughing and asthma attacks, and may shorten life. Warmer temperatures make ozone more likely to form and harder to clean up.

“Every American deserves to breathe healthy air that won’t make them sick. The American Lung Association calls on the administration and Congress to protect and prioritize Americans’ health by taking urgent action to fight air pollution and address climate change,” Wimmer said.

Chris Jennewein

Chris Jennewein is Editor & Publisher of Times of San Diego.