RAGES

As one of three components of WISSARD (Whillans Ice Stream Subglacial Access Research Drilling), RAGES (Robotic Access to Grounding-zones for Exploration and Science) research concentrates on the stability of the fast flowing Whillans Ice Stream grounding zone. A grounding zone is an area where the ice, ocean waters and sea floor interact; where the ice is being melted by or is freezing seawater, and where debris below and in the ice and streams flowing under the ice are released and discharge their loads. Based on our present limited data and modeling efforts, grounding zones can be influenced by: (i) internal ice stream dynamics, (ii) rates of subglacial sediment (till) supply to the grounding zone, (iii) increased melting by warming ocean waters, and/or (iv) filling/draining cycles of subglacial lakes.   Grounding zones are seen as high priority targets to investigate because models indicate these are important areas that strongly influence ice sheet stability.

Eight of Antarctica’s recognized geoscience researchers from six U.S. universities will lead RAGES through its planning years and field season in the austral summer of 2013-14. The RAGES field-sampling plan integrates surface geophysical surveys with borehole and subglacial sampling and measurements. The boreholes provide:

These data will allow RAGES scientists to address three main goals, which are to assess: (i) how the grounding-zone controls stability of the West Antarctic Ice Sheet (WAIS), (ii) how WAIS dynamics have changed in the past based on information stored in the “library” of grounding-zone sediments; and (iii) how important microbial activity and subglacial weathering is in supplying nutrients to the ocean both under the Ross Ice Shelf and potentially through the highly productive Southern Ocean.

The RAGES project not only addresses scientific questions of direct societal relevance and significance, it also represents major advances in polar technology. Unique instruments are being custom-designed and built for use in RAGES and they will advance the level of sophistication in polar instrumentation and data collection. Examples of this instrumentation are: a multi-sensor SIR (Sub-Ice ROVer (Remotely Operated Vehicle)), GIPSIE (Geochemical Instrumentation Package for Sub-Ice Exploration), a new design in percussion corer for sediment sampling, and a modified ITP (Ice-Tethered Profiler) that collects profiles of oceanic data while remotely driving itself up and down a wire through the water column. More detailed descriptions of the instruments are available here on the Technology tab.

 

 

Our biggest unknowns in trying to estimate the magnitude and rate of future global sea-level rise come from a poor understanding of ice sheet dynamics and ice sheet vulnerability to warming of oceans and atmosphere. Complete disappearance of the West Antarctic Ice Sheet alone would contribute 3-5m to global sea-level rise, making it a focus of scientific concern due to its possible susceptibility to internal or ocean-driven instability. Data from RAGES will contribute to a scientific community effort to develop more realistic ice-sheet models that can lessen our uncertainties about future ice sheet changes and sea.

After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Construction of the subglacial drill and development of the wide range of RAGES science instrumentation mentioned above, will enhance high-level skills and know-how in the US polar engineering community. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007).

 RAGES scientists are integrated into the WISSARD Education and Outreach program. The project will train a cohort of new young scientists in a setting of multidisciplinary, integrated Antarctic science with heavy student involvement in development and application of advanced technologies to Antarctic field research. Furthermore, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be the last unexplored aquatic environments on Earth. In these efforts, RAGES scientists will be supported by experienced K-12 educators, informal educators, and renowned science journalists, some of whom will have the opportunity to report from the field during RAGES deployments in 2011-12 and 2013-14.