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CNR: Alamanacco della Scienza


N. 3 - 13 feb 2013
ISSN 2037-4801

International info   a cura di Cecilia Migali


First intact samples from an Antarctic subglacial lake

Following more than a decade of international and national planning, three and a half years of project preparation, and an intense week of on-ice weather delays, the Wissard (Whillans Ice Stream Subglacial Access Research Drilling) field team has successfully drilled through the overlying ice sheet and sampled directly the waters and sediments of subglacial lake Whillans. This effort marks the first successful retrieval of clean whole samples from an Antarctic subglacial lake. Water and sediment samples returned to the surface are now being processed to answer seminal questions related to the structure and function of subglacial microbial life, climate history, and contemporary ice sheet dynamics. Video surveys of the lake floor and in-situ measurements of selected physical and chemical properties of the waters and sediments are further allowing the team to characterize the lake and its environs.

The interdisciplinary team of Wissard scientists represents a consortium of US universities and two collaborating international institutions, the British one, lead by Andrew Mitchel, and the Italian one, lead by Carlo Barbante of the Cnr-Institute for the Dynamics of Environmental Processes (Idpa) and University of Venice. This team includes experts on life in icy environments (led by John Priscu, Montana State University), glacial geology (led by Ross Powell, Northern Illinois University) and glacial hydrology (led by Slawek Tulaczyk, University of California, Santa Cruz). The mutual expertise by these groups will allow the data collected to be cast in a systemic, global context. Access to the lake required drilling through 800m of ice using a specialized hot-water drill, fabricated and operated by a team of engineers and technicians directed by Frank Rack (University of Nebraska - Lincoln).
The drill was fitted with a filtration and germicidal Uv system to prevent contamination of the subglacial environment and to recover clean samples for microbial analyses. In addition, the numerous customized scientific samplers and instruments used for this project were also carefully cleaned before being lowered into the borehole through theice and into the lake. Such cleaning ensured that we met internationalguidelines as stewards of this isolated environment while at the same time protecting the integrity of the precious samples recovered. Wissard's groundbreaking exploration of Antarctica's subglacial environment marks the beginning of a new era in polar science, opening the window for future interdisciplinary scientific investigations of one of Earth's last unexplored frontiers. Thanks in large part to the education and outreach components of Wissard, the project has been followed closely by people across the globe and the participants hope that their efforts will inspire the next generation of polar scientists.
Wissard science and logistical endeavors have endured numerous challenges during both the inception and implementation of the project. "We could not have succeeded without the extraordinary support afforded by the 139th Expeditionary Airlift Squadron of the NY Air National Guard, Kenn Borek Air, and by many dedicated individuals working as part of the Antarctic Support Contractor, managed by Lockheed-Martin", the Consortium states.

Core funding for the Wissard project came from the National Science Foundation - Office of Polar Programs (Nsf-Opp; www.nsf.gov/dir/index.jsp?org=OPP), with additional funds for instrument development provided by the National Aeronautics and Space Administration - Cryospheric Sciences Program (Nasa-Csp; http://ice.nasa.gov/), National Oceanic and Atmospheric Administration (Noaa; www.noaa.gov/), and the Gordon and Betty Moore Foundation (www.moore.org/).

Fonte: Carlo Barbante, Istituto per la dinamica dei processi ambientali, Venezia, tel. 041/2348942, email carlo.barbante@idpa.cnr.it

Per saperne di più: - www.wissard.org