Summarizes what is known about two major variables involved in certain types of chemical pollution that seem to be changing the structure of the Earth's atmosphere. Discusses the greenhouse effect and the ozone layer. (TW)

While the open oceans remain relatively unpolluted, many coastal areas are suffering from oil, sewage, industrial wastes, and agricultural run-off. This document presents some of the key facts related to these kinds of water pollution. It focuses on the major sources of contamination in the world's seas, and provides an overview of how these…