Milwaukee under ozone advisory Monday: what that means and what to do

Madeline Heim, Milwaukee Journal Sentinel
·2 min read

Five counties along the shoreline of Lake Michigan — including Milwaukee County, where thousands are gathered for the Republican National Convention — are under an ozone advisory until 9 p.m. Monday night.

In addition to Milwaukee County, the Wisconsin Department of Natural Resources issued the advisory for Kenosha, Racine, Ozaukee and Sheboygan counties starting at 2:30 p.m.

Ozone forms when gases released from cars, power plants, chemical plants and other sources mix with sunlight and heat, according to the Wisconsin Department of Health Services. It's why most ozone alerts happen in the summertime. Southeast Wisconsin was hot and humid Monday.

The counties along the shore of Lake Michigan are the ones most often impacted by unhealthy ozone levels, according to the health department.

More: July 4 fireworks caused brief but hazardous air pollution in Milwaukee

Being exposed to too much ozone in the air can cause health problems like a sore throat, shortness of breath, coughing and headaches, especially for people with underlying health issues. Monday's ozone levels were expected to be "unhealthy for sensitive groups," according to the DNR advisory, meaning children, older adults, people who are active outdoors (including outdoor workers) and people with lung diseases such as asthma should reduce prolonged or heavy outdoor exertion.

As the climate warms, there will be more chances for unhealthy summertime ozone levels. Hotter summers are also making stagnant air days more frequent, according to an analysis from Climate Central, a nonprofit news organization that analyzes and reports on climate science. During those stagnation events, pollutants like ozone get trapped and make breathing more difficult.

To protect yourself when the air is unhealthy, the health department recommends the following:

  • Stay inside with windows closed if possible. Take it easy if you have to be outside, and limit outdoor playtime for children.

  • Follow your asthma action plan if you have asthma and take medications as prescribed. Always have your quick relief inhaler and spacer with you.

  • Take frequent indoor breaks and avoid strenuous activities if you live or work outdoors.

  • Exercise or play outside early or late in the day since ozone levels peak in the afternoon to evening.

Madeline Heim is a Report for America corps reporter who writes about environmental issues in the Mississippi River watershed and across Wisconsin. Contact her at 920-996-7266 or mheim@gannett.com.

This article originally appeared on Milwaukee Journal Sentinel: Milwaukee County under ozone advisory until 9 p.m. Monday