Wallace Smith Broecker is the Newberry Professor in the Department of Earth and Environmental Sciences at Columbia University and a scientist at Columbia's Lamont-Doherty Earth Observatory. He developed the idea of a global "conveyor belt" linking the circulation of the global ocean and made major contributions to the science of the carbon cycle and the use of chemical tracers and isotope dating in oceanography. Broecker has received the Crafoord Prize and the Vetlesen Prize. He was born on November 29, 1931 in Chicago, Illinois, United States. Broecker has authored over 450 journal articles and 10 books. He is perhaps best known for his discovery of the role played by the ocean in triggering the abrupt climate changes which punctuated glacial time, in particular the development and popularization of the idea of a global "conveyor belt" linking the circulation of the global ocean. However, his contributions stretch far beyond the "conveyor"; his work is the foundation of carbon cycle science, and his applications of radiocarbon to paleoceanography are landmarks in the field. His work with chemical tracers in the ocean is integral to modern chemical oceanography; indeed, his textbook "Tracers in the Sea", authored with Tsung-Hung Peng, is still cited in the contemporary literature 25 years after its publication. Broecker is a Fellow of the American Academy of Arts and Sciences and the National Academy of Sciences, Foreign Member of the Royal Society, and a Fellow of the American Geophysical Union and European Geophysical Union. He has received the Crafoord Prize in Geoscience, the National Medal of Science in 1996.