Comap, and other programs, but much more information is needed, and is available, in the arctic stratigraphic record to elucidate the processes involved.

Pilot studies have demonstrated the potential of arctic paleoecology and paleontology for documenting the Cenozoic migration history of some circum-arctic terrestrial organisms between Eurasia and North America and of some marine taxa between the Atlantic and Pacific Basins via the Arctic (Marincovich et al., 1990). More details on these migrations would improve understanding of marine benthic faunal relationships and correlations between the eastern and western hemispheres. Arctic terrestrial taxa were adapted to long periods of winter darkness and summer daylight, and as the climate changed, the successful terrestrial and marine organisms adapted to cold. Study of the adaptations that permitted these organisms to flourish under polar conditions and comparison of their taxonomic and paleobiogeographic relations to kindred forms at lower latitudes should contribute significantly to interpretation of the fossil records elsewhere, and possibly of the mechanisms and rates of evolution and of the adaptations of organisms to extreme environments.

As noted earlier, a large volume of the greenhouse gas methane is apparently held in gas hydrate deposits beneath the Arctic Ocean. Although not unique to the Arctic, the volume of methane estimated to reside in arctic hydrates makes its stability a significant concern. Either warming of arctic bottom waters during interglacial ages (such as the present time) or lowering of sea level during ice ages, acting alone, could cause partial decomposition of methane hydrates and foster the release of methane to the environment. Because the release of large volumes of methane to the atmosphere could have severe and sudden climatic consequences and because decomposition of methane hydrates may provide positive feedback to processes of climate change, the distribution, volume, composition, and stability of the large gas hydrate deposits of the Arctic Ocean Basin are of global concern. Modeling the effect of change in sea level and bottom water temperature on the stability of hydrate deposits in the Arctic would enable assessment of the role of gas hydrate in global climate change.

More speculative opportunities for polar geoscience research with global significance involve the high magnetic flux and steep magnetic lines of force that occur near earth's magnetic poles. Because of this configuration of the lines of force, the modest shielding from charged particles that is provided by earth's magnetic field is weakest in the polar regions. As a result, these regions are characterized by a relatively high flux of cosmic radiation and extraterrestrial particulate matter that possibly has imprinted the fossil and sedimentary record in the Arctic Ocean Basin. It is important to know whether Arctic Ocean Basin sediments contain elements, such as beryllium, osmium, and iridium, in amounts significantly exceeding their crustal abundance and how such anomalous amounts, if found, vary with time. Such variations might provide a geologic-scale record of solar-terrestrial interaction and perhaps augment other observations of variations in the strength of earth's magnetic field through time.

Many geologic processes and biological adaptations are best developed and therefore can be best studied in the Arctic. In this report, we focus on those geologic processes and environments that are most apt to have left a record in the solid earth that is useful for interpreting ancient environments. Examples include the character and volume of clastic and organic sediment incorporated in sea ice and the mechanisms by which this sediment is entrained and expelled from the sea ice to rain on the seabed, minerals that record ancient physical conditions in marine sediments, and organic compounds in fossil organisms that record ancient oceanographic conditions. This understanding would be most useful when applied to the Late Neogene and Quaternary stratigraphic record in the Arctic, which was affected by periodic episodes of continental glaciation and perennial sea ice. It would also contribute to our ability to interpret glacial and periglacial deposits in more ancient strata throughout the world. Many arctic geologic processes are important because they affect human economic activities in the region, and some of these economic activities could have adverse impact on the arctic environment.