Wisconsin DNR releases 2023 data for air quality in state

The Wisconsin DNR has released its air quality trends report to include data from 2023.

The trends show that while most pollutants regulated under the Clean Air Act have been decreasing across the state since monitoring began, the state faces tough challenges in continued reductions. In recent years, the report shows that ozone and particulate matter concentrations have plateaued or recorded increases.

Much of this can be attributed to the increase in wildfires in other parts of the country and in Canada. During the 2023 wildfire season, over 15 million hectares were burned in Canada. More than six times the annual average. In eastern Canada, more land was burned in southern Quebec in a 25 day period in June last year than in the past 20 years combined. These impacts resulted in some of the highest particulate matter readings ever recorded in the state.

While the state has seen improvements along the Lake Michigan shoreline, an area historically impacted by elevated ozone concentrations, the Milwaukee area and parts of Kenosha and Sheboygan
counties remain in nonattainment for the 2015 ozone standard.