A subterranean world of interconnected salty lakes that may support a microbial ecosystem lies beneath one of Antarctica's most barren and lifeless regions, scientists have discovered.
The aquifer network extends to a depth of up to 1,148ft (350m) below the McMurdo Dry Valleys, the coldest and driest desert on Earth.
A hoop-like electromagnetic sensor suspended beneath a helicopter was used to map the hidden subsurface. WORDS: PA.
Measurements of electrical resistivity revealed extensive, connected bodies of liquid salty water deep beneath the region's glaciers and lakes.
The network stretched from the coast for a distance of at least 7.5 miles (12km) inland.
US lead researcher Dr Jill Mikucki, from the University of Tennessee, said: "It may change the way people think about the coastal margins of Antarctica.
"We know there is significant saturated sediment below the surface that is likely seeping into the ocean and affecting the productivity of things that feed ocean food webs. It lends to the understanding of the flow of nutrients and how that might affect ecosystem health."
The findings, published in the journal Nature Communications, may shed light on how Antarctica has responded to climate change, said the researchers.
Cold and vegetation free, the Dry Valleys represent the nearest thing on Earth to a Martian environment.
Evidence suggests that the salty groundwater exists at below-freezing temperatures within the range tolerated by microbial life.
The McMurdo Dry Valleys, situated along the Ross Sea coastline and discovered by polar explorer Robert Scott in 1903, is the largest region in Antarctica not covered by an ice sheet.
It consists of an arid expanse of mostly dirt, small rocks and large boulders, dotted with a few frozen lakes.
Co-author Professor Ross Virginia, from Dartmouth College in New Hampshire, said: "This fantastic new view beneath the surface will help us sort out competing ideas about how the McMurdo Dry Valleys have changed with time and how this history influences what we see today."
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