Wallace Smith Broecker - geologist and geochemist - is one of the world's leading interpreters of the Earth's climate system. After receiving B.A. and Ph.D. degrees from Columbia University, he joined the faculty of Columbia, where he has been the Newberry Professor of Geological Sciences since 1977. Dr. Broecker pioneered new approaches to studying the Earth's climate, including the use of radiocarbon and other chemical isotopes from marine sediments. His investigation of oceanic cycles and the relationship of the oceans and the atmosphere has advanced our understanding of climate change. He has played an active role in environmental policy debate as a leading voice warning of the potential danger of increased greenhouse gases in Earth's atmosphere. The author of several textbooks and more than 400 scientific articles, Dr. Broecker is a member of the National Academy of Sciences and the American Academy of Arts and Sciences. His numerous honors include the National Medal of Science, the nation's highest scientific award, and the Blue Planet Prize for achievements in global environmental research. For his outstanding contributions to our understanding of the Earth's past climate and environmental issues related to its future, Southern Methodist University is honored to confer upon Wallace S. Broecker the degree of Doctor of Science, honoris causa.