Understanding Ozone and the AQI

Ozone Forecast and the Air Quality Index

MDEQ issues a daily AQI ozone forecast from March 1st to October 31st for the Mississippi Gulf Coast, Jackson Metro area, and DeSoto County. This is made available to the general public as well as being provided to weather media for inclusion in daily weather reports.

*Ozone forecast will be updated on Airnow.gov by 2:45 p.m. daily.

What is Ozone?

Ozone is a gas composed of three atoms of oxygen. Ozone occurs both in the Earth’s upper atmosphere and at ground level. Ozone can be good or bad, depending on where it is found:

Good Ozone

Ozone occurs naturally in the Earth’s upper atmosphere—6 to 30 miles above the Earth’s surface— where it forms a protective layer that shields us from the sun’s harmful ultraviolet rays. This beneficial ozone is gradually being destroyed by manmade chemicals. An area where the protective “ozone layer” has been significantly depleted—for example, over the North or South pole—is sometimes called “the ozone hole.”

Bad Ozone

In the Earth’s lower atmosphere, near ground level, ozone occurs naturally at lower amounts and additional ozone is formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources react chemically in the presence of sunlight. Ground-level ozone at elevated levels is a harmful air pollutant.

What does the AQI mean?

How can I help?

Every day, the choices we make can increase or decrease air pollution and can protect or threaten our health. By making simple changes to our home, transportation, and consumer habits we can help reduce air pollution.

  • Drive less, especially during peak traffic periods or hot days.
  • On ozone action days, delay maintenance on your home (e.g., mowing your lawn, painting, et cetera).
  • Use public transportation, walk, or ride a bike.
  • Shop by phone, mail or Internet.
  • Telecommute.
  • Combine your errands into one trip.
  • Avoid revving or idling engine over 30 seconds.
  • Avoid waiting in long drive-through lines. Turn off your car and go in.
  • Accelerate gradually, maintain speed limit and use cruise control on the highway.
  • Follow your owner’s manual on recommendations for maximum economic efficiency.
  • Use compact florescent lights with energy-efficiency lighting and other energy-efficient appliances.
  • Turn off appliances and lights when you leave the room. Use the microwave to cook small meals. (It uses less power than an oven.)
  • Plant deciduous trees in locations around your home to provide shade in the summer, but to allow light in the winter.
  • Recycle paper, plastic, glass bottles, cardboard and aluminum cans. (This conserves energy and reduces production emissions.)
  • Reuse materials like paper bags and boxes when you can.
  • Properly dispose of household paints, solvents and pesticides. Store these materials in airtight containers.
Other Useful Information

For more information on ozone or the AQI contact Rodney Cuevas at 601-961-5566.