In the troposphere, ozone is pollution. In the stratosphere, we find the "good" ozone that protects life on earth from harmful rays from the Sun.
Click on image for full size
Courtesy of COMET program

Ozone - An Overview

Have you ever heard of ozone? That's a word that shows up in the news a lot! Do you know what ozone is and why it is important in the Earth's atmosphere?

Ozone is made of three oxygen atoms (O3). You've probably heard of oxygen before -- it's part of the air we breathe. The oxygen that we breathe is made up of two oxygen atoms (O2). Add another oxygen atom, and you have ozone! When a lot of ozone is around, you would see it as a pale blue gas. Ozone is found in two different layers of the atmosphere, the stratosphere and the troposphere. Where we find ozone in the atmosphere determines whether we consider it to be "good" or "bad"!

In the troposphere, the ground-level or "bad" ozone is an air pollutant that damages human health and plants. It is a key ingredient in smog. In the stratosphere, we find the "good" ozone that protects life on Earth from the harmful effects of the Sun. The simple saying "Good up high and bad near by" sums up ozone in the atmosphere.

Last modified January 8, 2007 by Jennifer Bergman.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Oxygen

Oxygen (O2) is a kind of gas. A lot of the air you breathe is oxygen. That's a good thing, since we need oxygen to stay alive! About 4/5ths of the air in Earth's atmosphere is nitrogen (N2). Almost all...more

Air Pollution

Have you ever heard of air pollution? Air pollution is not new. 700 years ago, when people started burning large amounts of coal 700 years ago in London, England, they complained about the dust and soot...more

Ozone

Ozone is a special kind of oxygen molecule. Normal oxygen molecules (O2), the kind we need to breathe, have two oxygen atoms. Ozone molecules (O3) have three oxygen atoms. Ozone forms when a photon of...more

Ozone in the Stratosphere

Most of the ozone that we know about is found in the the stratosphere, the second layer of the Earth's atmosphere. Ozone forms a kind of layer in the stratosphere. This layer shields us from the Sun's...more

Space Missions to study Earth's Atmosphere & Climate

Some satellites study Earth from space. Some of them study our atmosphere and weather. Some take pictures of clouds. Others use special instruments to make measurements of temperature, humidity, or the...more

Atmospheric Chemistry of Earth's Troposphere

When you think of chemistry, do you think about mixing colored liquids in test tubes and maybe making an explosion... or at least a nice puff of smoke? Did you know that a lot of chemistry happens in Earth's...more

Health Standards Exceeded by Ozone Pollution in Wildfires

Scientists from the National Center of Atmospheric Research (NCAR) have published a new paper about how wildfires affect air pollution. They have learned that wildfires make ozone levels high enough to...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA