Introduction

During the past forty years, rapid technological growth has advanced the ability of satellites to observe and monitor the global ocean and its overlying atmosphere. Because of similar advances in computer hardware and software, it is now possible to acquire and analyze, at short time delays, large satellite data sets such as the global distribution of ocean waves, the variations in sea surface height associated with large-scale current systems and planetary waves, surface vector winds and regional and global variations in ocean biology. The immediate availability of these data allows their assimilation into numerical models, where they contribute to the prediction of future oceanic weather and climate.

The ocean covers approximately 70% of the Earth's surface, is dynamic on a variety of scales, and contains most of the Earth's water as well as important marine ecosystems. The ocean also contains about 25% of the total planetary vegetation, with much of this restricted to a few coastal regions (Jeffrey and Mantoura, 1997). Regions of high biological productivity include the Grand Banks off Newfoundland, the Bering Sea and Gulf of Alaska, the North Sea and the Peruvian coast. Between 80% and 90% of the world's fish catch occurs in these and similar regions. For its role in climate, determination of the changes in ocean heat storage and measurement of the vertical fluxes of heat, moisture and CO2 between the atmosphere and ocean are critical to understanding global warming and climate change.