Scientists have confirmed that the waters and sediments of a lake that lies 2600 feet beneath the Antarctic ice sheet support “viable microbial ecosystems,” a finding that has implications for life in other extreme environments both on Earth and planets elsewhere in the solar system.
Their work, supported by the National Science Foundation (NSF), appears in the most recent issue of the journal Nature.
Knut Christianson, a post-doctoral fellow in the laboratory of Courant Institute of Mathematical Sciences Professor David Holland, is among the paper’s co-authors.
The researchers note that, given the more than 400 sub-glacial lakes and numerous rivers and streams that are thought to exist beneath the Antarctic ice sheet, such ecosystems may be widespread and influence the chemical and biological composition of the Southern ocean, which encircles the continent.
“Hidden beneath miles of ice in Antarctica is an unexplored part of our biosphere,” explains Brent Christner, a researcher with the NSF-funded Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project and a professor of biology at Louisiana State University. “WISSARD has provided a glimpse of the nature of microbial life that may lurk under more than five million square miles of ice sheet.”
WISSARD is backed by a $10 million, five-year National Science Foundation grant to study the impact of global warming on the Antarctic Ice Sheet, an undertaking that will provide a method for measuring effects of oceanic and atmospheric warming in other regions. Holland, director of the Center for Atmosphere Ocean Science, part of the Courant Institute, is the principal investigator on the NYU team.
Analysis of the samples taken from Subglacial Lake Whillans show that the lake water contains a diverse microbial community, many members of which can mine rocks for energy and use carbon dioxide as their source of carbon.
Their conclusions stem from a ground-breaking scientific and engineering maneuver conducted in January 2013. The WISSARD team used clean hot-water drilling technology to access Subglacial Lake Whillans. This permitted the retrieval of pristine water and sediment samples that had been isolated from direct contact with the atmosphere for many thousands of years.
The realization that vast aquatic system of rivers and lakes that exist beneath the ice in Antarctica has spurred investigations to examine their effect on ice sheet stability and the habitability of environments at the bed. The latest WISSARD announcement is the first to provide definitive evidence that a functional microbial ecosystem exists beneath the Antarctic ice sheet, confirming more than a decade of speculation about life in this environment.
“Given the prevalence of subglacial water in Antarctica,” the researchers conclude, “our data …lead us to contend that aquatic microbial systems are common features of the subsurface environment that exists beneath the … Antarctic Ice Sheet, which may have significant roles in stimulating Southern Ocean primary productivity.”
Co-authors on the paper include students and researchers from Louisiana State University; the University of Venice in Italy; the Scripps Institution of Oceanography; St. Olaf College in Minnesota; the University of Tennessee; and Aberystwyth University in the United Kingdom.
WISSARD is funded under NSF's American Recovery and Reinvestment Act of 2009 (ARRA) portfolio. NASA’s Cryospheric Sciences Program, the National Oceanic and Atmospheric Administration (NOAA), and the Gordon and Betty Moore Foundation also provided support for the project.