Coulman High Project Site Survey Interdisciplinary Outcomes: What Lies Beneath The Ross Ice Shelf
Abstract
The ANDRILL Coulman High (CH) Project Site Surveys were an international effort conducted from November 2010 through January 2011. These surveys achieved all their primary and secondary objectives and resulted in an unexpected biological discovery at the lower boundary of the Ross Ice Shelf (RIS), which demonstrates the role of serendipity in scientific research. The surveys followed a safe traverse route to CH across the RIS using a ground-penetrating radar system supplemented by previously collected airborne radar. Four GPS stations and a weather station were established to monitor lateral and vertical ice motions and environmental conditions. A series of combined US-NZ field camps on the RIS were occupied and the ANDRILL hot water drill (HWD) system was used to melt numerous holes through 250-275 meters of ice shelf. Oceanographic moorings comprised of inductive sensors were deployed through the RIS at two sites and were recovered to the ice surface after two months. The NZ mooring was redeployed to conduct long-term observations through the water column at CH. Video camera observations of the interior and basal surface of the ice shelf and benthic observations of the seafloor were integrated with conductivity-temperature-depth (CTD) measurements at each site. The Submersible Capable of under-Ice Navigation and Imaging (SCINI) underwater remotely operated vehicle (ROV) was deployed at two sites through 260 meters of ice to explore the underside of the ice shelf while conducting operational testing. This was the first time that SCINI was deployed through an ice shelf. SCINI discovered an unusual biological community living in the ice at the lower surface of the ice shelf and recovered biological samples using an improvised suction pump sampler. These samples and extensive imagery are being further investigated to determine the nature of this newly discovered ecosystem. The biological discovery at the base of the RIS highlights the importance of continued interdisciplinary investigations at the base of the ice shelf and within the ice shelf cavity. These investigations should be integrated with water column measurements and benthic studies. A proposal is being developed to enhance the capabilities of the SCINI ROV to permit extended dives to full water depth (>800 m) in the sub-ice cavity of the Ross Ice Shelf, both to assist with ANDRILL Coulman High Project requirements and to enable a wide range of potential interdisciplinary studies. This enhanced ROV, which will equipped with a gripper and other instruments, will be used to support proposed drilling operations, and will perform observational missions across significant distances from the base of the ice shelf to the seafloor.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFMPP33B1935R
- Keywords:
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- 0456 BIOGEOSCIENCES / Life in extreme environments;
- 0728 CRYOSPHERE / Ice shelves;
- 3080 MARINE GEOLOGY AND GEOPHYSICS / Submergence instruments: ROV;
- AUV;
- submersibles;
- 4207 OCEANOGRAPHY: GENERAL / Arctic and Antarctic oceanography