What role does the ocean play in global climate change? Although not fully understood, there is general agreement that it is significant. Therefore, the scientific community has initiated large-scale research programs based on studies of the ocean and its relation to global climate and climate-related processes. This volume provides brief summaries and reports on the progress of the major oceanographic research programs. It looks at both programs that study processes that occur over periods ranging from days to hundreds of years–the contemporary system–and those that seek to understand long-term variations ranging from thousands to millions of years–the geological perspective.