The end of ozone forecasting season is nigh

The Virginia Department of Environmental Quality 2021 ozone pollution forecasting season has come to an end.

Overall, air quality remains good throughout the Commonwealth, although Virginians experienced more poor air quality days in 2021 than in the previous year.

Virginians saw a record number of good air quality days in 2020 in part due to the reduction in traffic related to the COVID-19 pandemic. In 2021, ozone pollution levels were slightly higher as a result of increased traffic and smoke associated with wildfires in the western part of the country and Canada.

Ozone pollution forms when volatile organic compounds and nitrogen oxides in the atmosphere react on hot, sunny days. The main sources of these chemicals are typically motor vehicle exhaust, power plants, industrial emissions and solvents. This year, however, wildfire smoke contributed to elevated levels of both ozone and particulate pollution throughout much of the summer.

On four separate days, there were unhealthy ozone pollution readings at one or more of DEQ’s air quality monitors throughout the state. This occurs when the average ozone concentration is greater than the 70 parts per billion standard, which can mean unhealthy conditions for some people, such as children, the elderly and those with heart or lung conditions. Monitors that measured high ozone pollution levels this year are in Northern Virginia, Stafford, Caroline and Chesterfield counties.

“Although we had a few more high ozone days in 2021 than we did in 2020, our long-term trend of achieving better air quality continues,” said DEQ Director David Paylor. “In past decades, we experienced far more bad air quality days each summer than we do now. But thanks to stronger controls on pollution and cleaner fuels, air quality continues to improve.”

“The challenges we experienced with our air quality this year show how environmental issues, such as wildfires, can affect people thousands of miles away,” said DEQ Air and Renewable Energy Director Mike Dowd.

Current regional air quality conditions and forecasts are available on DEQ’s website.