to represent a coherent set of research initiatives, the fact that the committee identified gaps is not unexpected. These gaps can be considered opportunities for future research, though some may not require a specific follow-on program.

The committee considered many sources in assessing gaps and follow-on activities. These included input from SSC questionnaires, the World Wide Web questionnaire, and input from a number of groups presently considering the initiation of large programs or the future of ocean science research in general. A considerable effort is being undertaken presently by the ocean science community to identify scientific challenges that may be pursued in the future. NSF/OCE has convened a series of discipline workshops¹ to help chart the future of research in the ocean sciences, including FUMAGES² (The Future of Marine Geology and Geophysics), OEUVRE³ (Ocean Ecology: Understanding and Vision for Research), APROPOS⁴ (Advance and Primary Opportunities in Physical Oceanography Studies), and FOCUS⁵ (Future of Ocean Chemistry in the United States. NSF/OCE presently has a group of scientists synthesizing the results from these four workshops. Given the extensive community involvement in these workshops, the committee determined it unnecessary to attempt to replicate or anticipate the outcome of these efforts. The reports of these workshops form a comprehensive view of the scientific challenges that may shape ocean research in the coming decades. Of particular interest is the degree of collaboration with other disciplines called for in each of the reports.

The following should be considered as a list of general scientific opportunities that may warrant a number of organized research efforts on a variety of scales. (For another recent assessment of future challenges by the Ocean Studies Board see Opportunities in Ocean Sciences: Challenges on the Horizon. [NRC, 1998]). The list below is not meant to be comprehensive, rather it was designed to highlight those activities that had some potential for near future activities, that would involve coordination across disciplines, and that represent scientific challenges of sufficient scale:

• The ocean's role in the hydrological cycle including freshwater fluxes, polar ice dynamics, and groundwater input, and effects of these exchanges on the circulation and heat flux, chemical species, and marine ecosystems.