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Ground-Level Ozone

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Ground-Level Ozone

Ozone

Ozone is a gas that you cannot see or smell. Good ozone occurs naturally about 10 to 30 miles above the Earth's surface. It makes a protective layer in the atmosphere that shields us from the sun's harmful ultraviolet rays. Ground-level ozone is created by chemical reactions at the Earth's surface.1 Ground-level ozone forms when fuel burned in cars and trucks, power plants, factories, and other sources react with heat and sunlight. Weather conditions and sunlight intensity also play a role in forming ground-level ozone. It is one of the biggest components of smog. Ground-level ozone is more likely to reach unhealthy levels on hot sunny days in urban areas but can be carried by wind to rural areas.2 Ground-level ozone is known as bad ozone because it can cause breathing problems, especially for sensitive groups like asthmatics or the elderly.

Ground-level ozone data are available on the MiTracking data portal.