Several counties in eastern Wisconsin are considered non-attainment areas for Ozone air pollution.  Additional counties, especially along the Fox River Valley, are on the verge of being designated as ozone non-attainment zones.
 

This means that during several days each year, these counties experience high concentrations of ground-level ozone in the air.   This can be extremely unhealthy to breathe, especially for people who already have respiratory problems - elderly adults, young children, and those who suffer from emphysema, bronchitis, asthma, lung cancer, or other breathing problems.  Studies show that hospital admissions and respiratory deaths often increase during periods when ozone levels are high. What is Ozone? Ozone is a gas which forms when several other types of air pollution recombine after exposure to the sun's radiant energy.   It's the main component of the hazy smog that hovers over eastern Wisconsin on certain hot days.

We often see a brown smog streak across the Fox River Valley skyline.

Car and truck emissions are a major sources of ozone, as are coal-fired power plants and large manufacturing industries.  Gasoline and other petroleum-based chemicals and solvents often vaporize directly into the atmosphere, contributing to ozone.   Lawnmowers and the starter fluid for backyard grills are two major residential sources.

Links to More Ozone Information

• Ozone Action Days in Wisconsin
• Summer Ozone Watch - Wisconsin Dept. of Natural Resources
• Daily Map of Changing Ozone Levels (Time Lapse) -- US Environmental Protection Agency
• Dirty Secrets... about clean air in Door County 

• Introduction to Air Pollution in Wisconsin
• How You Can Help Reduce Air Pollution
• Incineration Concerns
• Global Warming
• Links to More Air Pollution Information