Science and Implementation Plan: Chapter 6

Related Research Programs

6.1. DOMESTIC PROGRAMS

Some of the research necessary for the attainment of the WAIS objectives is already being supported or planned under the auspices of active domestic programs. The WAIS program provides a framework that connects portions of these independent activities, along with new investigations, and focuses them sharply so that multidisciplinary questions of major global importance are answered.

Reports describing each of these projects already have been written. Here, only a brief description is given to identify how each project relates to the WAIS program.

6.1.1. Siple Coast Project

The Siple Coast Project (SCP) was a glaciological study begun in 1983 concentrating on the Ross Embayment sector of the West Antarctic ice sheet (SCP Steering Committee, 1988). In accord with the SCP Science Plan (SCP Steering Committee, 1988), major field activities terminated by 1994 and a smooth transition to WAIS investigations has taken place. The SCP discovered that significant changes in the ice sheet were occurring, forming the urgent basis for WAIS. Along with the discovery of major mass imbalances and changes in ice velocities, SCP investigators revealed the existence of a thick, extensive subglacial layer with mechanical properties that are probably responsible for the rapid motion of the ice streams.

The SCP goals were to determine the ice-sheet's current configuration and mass balance, to identify the physical controls on ice flow, and to predict the future behavior of the ice in this region. While the first goal was met, and major progress was made on the second, it became increasingly apparent during the SCP that the prediction of the future of a marine ice sheet is not solely a glaciological problem. Attaining this final goal requires an understanding of the complex nature of interaction between the ice, the underlying lithosphere, the ocean and the atmosphere; WAIS is designed to provide this understanding and has solid roots in the SCP. The unanswered questions of the SCP have transferred unaltered into the ice-dynamics component of WAIS.

6.1.2. Antarctic Geophysical Initiative

The Antarctic Geophysical Initiative (AGI) is a 10-year program begun in 1990, focusing on Antarctica's tectonic evolution and its role in paleoenvironmental change that culminated in the Cenozoic glaciation (Workshop Report on the Antarctic Lithosphere, 1988). The initial thrust of this program also is in West Antarctica. All of the geophysical data collected as part of the AGI will contribute to the objectives of WAIS and, similarly, the geological and geophysical undertakings of WAIS will contribute to a better understanding of both the tectonic evolution and paleoenvironmental history of West Antarctica. It is expected that the similar geological, geophysical and geographical foci of AGI and WAIS will result in close cooperation.

6.1.3. Global Ice-Core Research Program

The Ice-Core Working Group (ICWG) has identified the West Antarctic ice sheet as the location for a deep and intermediate coring program following the completion of the Greenland Ice Sheet Project-2 (GISP2) hole (ICWG, 1989). At a joint meeting in 1994 of the ICWG and the WAIS Working Group, these groups decided to merge the goals of the two projects and to fully incorporate the ICWG recommendations for West Antarctic ice cores (WAISCORES) into the WAIS project. This inclusion spawned the second major question for WAIS to address, and significantly strengthened each project by providing a solid link between these two strongly related Antarctic efforts.

The primary goals of WAISCORES are: to determine the response of the West Antarctic ice sheet to the warmth of the last interglacial; to reconstruct a high-resolution, multiparameter history of the ice sheet and the overlying atmosphere; and to elucidate the interaction between climate, ice-sheet size, and sea level. Comparison of this record with that from GISP2 should allow assessment of the critical timing and phase relationships of global environmental changes affecting both Greenland and Antarctica.

The location of the deep core is being proposed along the ice divide in West Antarctica, a region where interests from the AGI and WAIS merge. The site selection for the planned deep and intermediate cores will clearly draw heavily on the wealth of data already collected by the SCP and eventually by the AGI and WAIS. The requirement of the coring program to know basal topography, current net balance, and 10-meter temperatures can be satisfied with SCP and AGI data. Additional requirements include confirmation of a frozen bed, local ice flow and meteorological sensitivity at the drill site. The first and third of these requirements are addressed by WAIS.

6.2. INTERNATIONAL PROGRAMS

The WAIS goals and objectives are not only of domestic interest. Many other nations have active research programs in West Antarctica and are concerned about the future of this ice sheet. Much of the research of Antarctic scientists in other countries is directly relevant to WAIS, but no other effort is as comprehensive, as focused, and as well coordinated as WAIS. WAIS must be viewed as the key research effort.

Major international programs with overlapping interests to WAIS are described below. As a minimum, these programs afford WAIS investigators opportunities for sharing of results and for initiating collaborative research. Stronger, more formal links could provide additional scientific insight and assistance with logistics.

6.2.1. Filchner-Ronne Ice Shelf Programme

Many nations have been active in West Antarctic research and are concerned about the future behavior of this ice sheet. The Working Group on Glaciology of the Scientific Committee on Antarctic Research (SCAR) has recommended that "an increased effort be put into field work as well as numerical simulation studies on ice shelves and associated oceanographic systems, in particular the Filchner/Ronne Ice Shelf and the southern Weddell Sea" (FRISP Reports). The Filchner-Ronne Ice Shelf Programme (FRISP) was initiated in 1973 shortly after this recommendation, and representatives of countries including Argentina, Germany, Great Britain, Norway, Sweden, the U.S., and Russia have agreed to cooperate in studying the glaciological regime of the ice shelf. FRISP research is limited to glaciological and oceanographic studies of a region far from major U.S. logistic bases. Nevertheless, this study area includes a major portion of West Antarctica, and close cooperation with these international scientists will be actively pursued by WAIS scientists.

6.2.2. Glaciology of the Antarctic Peninsula

There are a number of countries conducting research in the Antarctic Peninsula under the Glaciology of the Antarctic Peninsula (GAP) program. The record of past ice-sheet configuration, oceanographic characteristics, and atmospheric circulation patterns produced by GAP researchers will be of obvious relevance to WAIS investigations. WAIS will maintain open communication with GAP researchers to keep them informed of planned WAIS investigations and important results, and to facilitate collaborations between investigators that will benefit each program.

6.2.3. International Geosphere-Biosphere Program

The International Geosphere Biosphere Program (IGBP) attempts to link together the research of many nations into a comprehensive study of the entire Earth climate system. The Scientific Committee on Antarctic Research (SCAR) identified a number of research tasks that "must be included in an Antarctic component of the IGBP" (SCAR, 1989). The list contains recommendations for studies of sea-ice/ocean/atmosphere interactions, the interaction of the Antarctic ice sheet and sea level, and the Antarctic paleo-environmental record. All of these are elements of WAIS and indicate the very useful contribution to the IGBP by WAIS.

6.2.4. International Trans-Antarctic Scientific Expedition

As proposed, the broad aim of the International Trans-Antarctic Scientific Expedition (ITASE) is to establish how the recent and present-day atmospheric environments are represented in the upper layers of the Antarctic ice sheet. The key scientific problems to be addressed include: the spatial representation of several environmentally related parameters measured in ice cores on a time scale of approximately the last 100 years; establishment of a basis for assessing recent environmental change in Antarctica; documentation of variations in the transport processes over the ice sheet; refinement of mass balance of the ice sheet; the linking of AWS data to data from air-sampling stations; and establishment of ground truth for future remote-sensing experiments. These objectives overlap with many of the WAIS objectives and key questions.

The primary product of ITASE would be a continental-scale map of several environmental parameters. This would serve as useful input into WAIS models. ITASE data would come from a series of 20-meter-long surface cores collected every 50-100 km along traverse routes distributed throughout the continent. Logistic support will be developed from an international pool, but several legs may depend on the logistic capabilities of one country. Many member countries of the International Ice Core Forum have taken part in the formulation of ITASE and it will be offered to SCAR for consideration as part of the IGBP. Ideally, the U.S. component of ITASE would be heavily weighted in West Antarctica and would benefit from close scientific and logistic cooperation with WAIS activities.

6.2.5. Ice-Sheet Research with ERS-1&2

Satellite remote sensing greatly improves the ability of scientists to study large regions of the Earth. In the polar regions, satellite data have been used to study surface morphologies of ice and rock, ice flow, meteorological phenomena, ocean currents, and the behavior of the sea-ice cover, to name only a few of the many possible applications. The European Space Agency's ERS-series of satellites have orbits which extend southward to 82¡S, covering a substantial portion of West Antarctica.

Ice-Sheet Research with ERS-1 (ISRERS-1) is an international collection of glaciologists who conduct a wide range of studies using the radar altimeter, the synthetic aperture radar (SAR), and the thermal sensor on the ERS satellites. Altimetry provides an accurate data base of surface elevation against which future altimetric surveys (perhaps with laser altimeters) can be compared to discover regions experiencing rapid thickness change. The synthetic aperture radar data from ERS-1 and -2 does not extend over much of West Antarctica because of the north-looking view of the sensor, but does provide preliminary data to glaciologists, oceanographers, and geologists. Analyses of these data will help determine the potential for using future SARs (such as the Canadian Radarsat), which will cover more of West Antarctica.

6.3. FUTURE PROGRAMS

On the horizon are a number of new satellite sensors that, if realized, will provide WAIS scientists with enhanced tools for the conduct of their research.

6.3.1. Radarsat

This Canadian satellite will carry a SAR with capabilities beyond what is currently available with the ERS-series SARs. Lower incidence angles and a range of resolutions will provide greater coverage and flexibility to more closely match investigation and data. The operations plan of Radarsat also includes two brief periods when the satellite will maneuver to enable complete mapping of the entire Antarctic ice sheet. This will be an unprecedented opportunity to collect a unique data set that is sure to be used in many WAIS investigations including glaciology, geology and oceanography.

6.3.2. Geoscience Laser Altimeter System

The Geoscience Laser Altimeter System (GLAS) instrument is planned to be flown as part of NASA's Earth Observing System (EOS) on a dedicated satellite in a higher inclination orbit than most polar orbiters to ensure its ability to cover most of the Antarctic ice sheet. The primary design goal of this system is to be able to measure the surface elevation of the ice sheet to an accuracy of 10 centimeters or better. The scientific goal of GLAS is to determine the mass balance of Earth's ice sheets.

GLAS will provide WAIS glaciologists with an extraordinary view of the dynamics of the ice sheet in a relatively short period of time after its launch (scheduled for 2002). Topographic roughness information will also be valuable for the geologists attempting to characterize landforms.