The term "ozone" has appeared in numerous magazine and newspaper articles and has been a subject of discussion on both radio and television. Despite all the publicity surrounding this term, however, many people are still confused by it. The confusion arises from the fact that ozone is both beneficial and harmful. We know that the ozone layer in the upper atmosphere acts as a filter for the sun's ultraviolet rays, reducing the amount of radiation that reaches the earth's surface. At ground level, though, high concentrations of ozone can be harmful.
The Ozone Layer
Ozone gas forms a layer all around the earth high in the stratosphere. It serves as a vital and effective protective barrier from the sun's ultraviolet rays. In recent years, scientists have sounded alarms internationally about the depletion of the ozone layer, citing chemical pollution as the major cause.
A specific class of chemical compounds called chlorofluorocarbons (CFCs) are most often identified as ozone destroyers. CFCs were once widely used in everything from air conditioner coolants to the propellant in aerosol cans but have now been banned in most developed nations, including the U.S.
Many scientists believe much more needs to be done to protect the ozone layer, and international efforts are ongoing.
Ozone pollution is really an increase in the concentration of ozone in the air at ground level. Because sunlight has a critical role in its formation, ozone pollution is principally a daytime problem in the summer months. Ground-level ozone is produced when sunlight combines with hydrocarbons and nitrogen oxide, two compounds produced by cars, trucks, factories, and power-generating plants, and found wherever gasoline, diesel fuel, kerosene, oil, or natural gas are combusted. Urban areas with heavy traffic, and large industrialized communities, are the primary areas with ozone problems.
When temperatures are high and there is...