DNR says Wisconsin air quality is improving, citing decrease in pollutant concentration

Wisconsin State Farmer
Overall ozone concentrations have decreased since 2001 along the Lake Michigan shoreline, according to the DNR's 2020 Air Quality Trends Report.

The Wisconsin Department of Natural Resources announced that the dairy state's air quality is improving because pollutants have become less concentrated in the atmosphere.

The 2020 Air Quality Trends Report, which has data through the end of 2019, found "significant reductions" in pollutants for which the Environmental Protection Agency has set national air quality standards. The report also said 95% of Wisconsin's population lives in areas that meet federal standards.

The Lake Michigan shoreline is especially of interest in the report as an area plagued with "elevated ozone concentrations," which the report now states has decreased the average ozone concentration by 25% in nearly two decades. The DNR said that due to this decrease, many shoreline areas are now meeting federal ozone standards, including Door and Sheboygan counties.

Some highlights of the report include a 63% decrease in nitrogen oxide emissions, which come from fuel burning at high temperatures through cars, trucks, boats and other sources. Nitrogen oxides are poisonous, reactive gases that can cause long-term damage to plants, people and the atmosphere.

The report also noted an 89% decrease in sulfur dioxide emissions, which is emitted by the burning of coal and oil. When combined with water, it forms sulfuric acid, which is harmful to plants and waterways. There was also a 60% decrease in carbon monoxide emissions, which can be fatal to people in large concentrations.

Some report data was derived from the US National Aeronautics and Space Administration (NASA) in studying satellite data to create maps of continuing nitrogen dioxide concentrations in the atmosphere. The Milwaukee area had the most notable nitrogen dioxide reductions between 2006 and 2019. The DNR attributed the reductions to better pollution policies from the state government as well as cleaner and more efficient energy solutions.

"State and federal air pollution control programs, as well as voluntary actions taken by companies and citizens, are responsible for the improvements in air quality in Wisconsin," said DNR air program director Gail Good. "The Air Management Program will continue to work with our partners to study and resolve remaining air quality concerns."