14 December 2010

Frigid Life May Be Powered By Heat

Posted by mohi

From the snowy reaches of Antarctica to Saturn’s frozen moon Titan, volcanoes have the potential to power life in these extreme environments. We’ll probably have to wait a little longer for confirmation of life on Titan, but Antarctica is right on our doorstep and visits don’t require traveling on rocket-propelled spacecraft.


Glaciers can harbor populous communities of microbes in the cracks and crevices throughout the ice, as well as in meltwater underneath it. Image courtesy of NASA/Goddard Space Flight Center Scientific Visualization Studio LIMA

In this morning’s session B21F “Cryospheric Biogeochemistry II,” Mark Skidmore of Montana State University described how volcanic activity beneath the Whillans Ice Stream in the West Antarctic Ice Sheet could be a significant source of carbon and energy for microbes.

Antarctica doesn’t seem like an ideal place for life–March of the Penguins notwithstanding–but once again, tiny microbes have found a way of thriving in an inhospitable place. As rivers of snow make their way to the ocean, their grinding passage makes way for more than just the next wave of glacial ice. Meltwater where the glacier slides along the ground creates an aquatic habitat, nutrients mixed in by pulverized rocks, and gases released from melting ice provide all the ingredients microbes need to live.

Research on Antarctic microbes is limited. Data on this hardy community come from only two spots–Lake Vostok in the interior of Antarctica and the Kamb Ice Stream on the West Antarctic Ice Sheet. Scientists hope to remedy this with a program called WISSARD (Whillans Ice Stream Subglacial Access Research Drilling) out of Montana State University and funded primarily by the National Science Foundation. Three projects under WISSARD will sample different parts of the ice stream in an effort to compile a more integrative picture of the physical, chemical and geobiological processes of life under glaciers.

The microbes that scientists have found living in Antarctica are genetically “similar to organisms that you could pull out of the face of a glacier in the Canadian high arctic or in Alaska,” said Skidmore. But Skidmore estimates that the geothermal activity underneath the Whillans Ice Stream could provide vastly more carbon and energy sources to microbes than do geothermal environments in places like Yellowstone. “It’s a big, big, big unexplored store of carbon and organic material,” said Skidmore of Antarctica.

And who knows, one day in the not too distant future, scientists may be able to compare life powered by volcanoes in Antarctica to life on Titan.

–Jane Lee is a science communication graduate student at UC Santa Cruz