The National Center for Atmospheric Research | UCAR | UOP
Home Our Organization News Center Education Research Tools Libraries

Current Research Spotlight

Previous Research Spotlights:


Black Sheep of the Atmosphere: Ground-Level Ozone

Over the past century, increasing numbers of people have been rushed to hospitals with breathing problems or require medication for asthma. Larger amounts of crops such as soybeans are decaying in the fields. In recent years, scientists have discovered that these health and environment problems are linked to ozone, a chemical compound in our atmosphere.

In the stratosphere layer of Earth’s atmosphere, ozone gas occurs naturally and is beneficial to life on our planet, forming a protective layer that shields Earth from harmful solar radiation. There is concern about the waning of stratospheric ozone, as its depletion can lead to increased health problems for people and problems for ecosystems. However, ozone in the troposphere has markedly different implications. Instead of its cousin, the protective blanket perched in the stratosphere, ground-level ozone--also called tropospheric ozone--is a destructive agent that is harmful to people, animals, and plants.

Both ozone in the stratosphere and ground-level ozone in the troposphere occur naturally. However, ground-level ozone is also formed through the activities of humans, such as the burning of fossil fuels or plants. During the past century the amount of tropospheric ozone has more than doubled, as populations, automobiles, and industry have increased and more fossil fuel is burned. To what degree troposphere ozone concentrations are due to humans and to what degree they are natural are topics of current research. Figuring out exactly how, where, and why ozone is formed in the troposphere is important for understanding how we can prevent air pollution and the dangerous health problems that ground-level ozone fosters.