Abstract

Ozone is one of the most important trace species in the atmosphere and the focus of several important environmental issues. Most ozone resides in the stratosphere where it plays a critical role in protecting the biosphere from harmful solar ultraviolet radiation. A variety of observations indicate that ozone in this region is decreasing due to heterogeneous processes involving anthropogenic chlorine. In contrast, ozone is increasing at the surface due to photochemical reactions between man-made nitrogen oxides and hydrocarbons. This elevated ozone adversely affects human health and vegetation and can be transported across regional and international boundaries. Finally, ozone is the only radiatively important trace gas that absorbs both incoming ultraviolet radiation and outgoing infrared radiation. The net effect of atmospheric ozone changes on the surface radiation budget will depend on where the vertical profile changes, particularly in the upper troposphere and lower stratosphere.

© 1994 Optical Society of America