Wisconsin's Air Quality Trends
There is a statewide network of 30 ozone monitoring sites and 19 fine particle (PM2.5) monitoring sites to measure ambient air quality in Wisconsin. In addition, the DNR monitoring network measures sulfur dioxide, nitrogen oxide and carbon monoxide. The DNR monitoring network is operated under a federally approved network plan, submitted and reviewed annually to ensure appropriate monitoring in all locations required by federal regulations.
Under the Clean Air Act (CAA), the U.S. EPA sets National Ambient Air Quality Standards for pollutants. Data from Wisconsin’s monitoring network is validated and reported to the EPA to demonstrate how well air pollution controls and programs are working to improve air quality and meet the federal standards. In addition, using continuous monitoring data, the DNR quickly informs the public when air pollution reaches unhealthy levels.
2020 Wisconsin Air Quality Trends Report
As part of its effort to meet CAA requirements, the DNR released the 2020 Wisconsin Air Quality Trends Report - data through 2019 (AM-583). The report shows that the overall air quality in Wisconsin continues to improve, building on a 20-year trend in the state.
To view charts that show the air quality trends in each county, see the 2020 Wisconsin Air Quality Trends by County (AM-584).
We continue to work toward attainment in all counties and ensure compliance with all federal air requirements.
- Committed to Clean Air - This 60-second video highlights some of the key successes in air pollution reduction in Wisconsin.
- Committed to Clean Air: Particle Pollution - Learn about particle pollution and key successes in air pollution reduction in Wisconsin.
- Committed to Clean Air: Ozone – Learn where ground-level ozone comes from, what the DNR is doing to regulate it and what citizens can do to help.
Previous Reports
- 2019 Wisconsin Air Quality Trends Report – data through 2018 (AM-574)
- 2019 Wisconsin Air Quality Trends by County (AM-575)
- 2018 Wisconsin Air Quality Trends Report - data through 2017 (AM-574)
- 2018 Wisconsin Air Quality Trends by County (AM-566)
- 2017 Wisconsin Air Quality Trends Report - data through 2016 (AM-553)
- 2016 Wisconsin Air Quality Trends Report - data through 2015 (AM-550)
- 2015 Wisconsin Air Quality Trends Report - data through 2014 (AM-534)
- 2015 Wisconsin Air Quality Trends Report - data through 2013 (AM-526)
- 2014 Wisconsin Air Quality Trends Report - data through 2012 (AM-523)
- 2013 Wisconsin Air Quality Trends Report - data through 2011 (AM-517)