A massive research project has fund that Antarctica isn’t a dead continent — there’s life deep beneath the ice.
A US study shows there’s an active ecosystem 800 metres below the surface of the West Antarctic Ice Sheet in a lake which hasn’t seen sunlight or felt wind for millions of years.
The life is in the form of microorganisms beneath the enormous Antarctic ice sheet which convert ammonium and methane into the energy required for growth.
Many of the microbes are single-celled known as Archaea, said Montana State University professor John Priscu, the chief scientist of the project called WISSARD.
He is also co-author of the study published in the journal Nature, an international weekly journal for all fields of science and technology.
“We were able to prove unequivocally to the world that Antarctica is not a dead continent,” Priscu said.
The data in the Nature paper is the first direct evidence that life is present in the subglacial environment beneath the Antarctic ice sheet.
Priscu said he wasn’t surprised the team found life after drilling through the ice to reach Subglacial Lake Whillans in January 2013.
He researches both the South and North Poles and this year will be his 30th field season in Antarctica.
More than a decade ago, he published two manuscripts in the journal Science describing for the first time that microbial life can thrive in and under Antarctic ice.
Five years ago, he published a manuscript where he predicted that the Antarctic subglacial environment would be the planet’s largest wetland, one not dominated by birds of typical wetland regions, but by microorganisms that mine minerals in rocks at subzero temperatures to obtain the energy to fuel their growth.
Many of the subglacial archaea use the energy in the chemical bonds of ammonium to fix carbon dioxide and drive other metabolic processes.
Another group of microorganisms uses the energy and carbon in methane to make a living.
According to Priscu, the source of the ammonium and methane is most likely from the breakdown of organic matter that in the area hundreds of thousands of years ago when Antarctica was warmer and the sea inundated West Antarctica.
He said that, as Antarctica continues to warm, vast amounts of methane, a potent greenhouse gas, will be liberated into the atmosphere enhancing climate warming.
The US team also proved that the microorganisms originated in Lake Whillans and weren’t introduced by contaminated equipment, Priscu said. Skeptics of his previous studies of Antarctic ice have suggested that his group didn’t actually discover microorganisms, but recovered microbes they brought in themselves.
“We went to great extremes to ensure that we did not contaminate one of the most pristine environments on our planet while at the same time ensuring that our samples were of the highest integrity,” Priscu said.
Planning to drill again this Australian summer in a new Antarctic location, Priscu said WISSARD was the first large-scale multidisciplinary effort to directly examine the biology of an Antarctic subglacial environment.
The Antarctic Ice Sheet contains 70% of Earth’s freshwater.
Lake Whillans is one of more than 200 known lakes beneath the Antarctic Ice Sheet. The river which drains Lake Whillans flows under the Ross Ice Shelf, which is the size of France, and feeds the Southern Ocean, where it can provide nutrients for life and influence water circulation patterns.