by Andy Coghlan

22 April 2016

from NewScientist Website

A plane flies over the ice Antarctic landscape
Not just ice underneath
 

Antarctica may be hiding a large lake under its ice - second only to Lake Vostok in size - according to data presented at the European Geosciences Union meeting in Vienna this week.

Such subglacial lakes are of great interest because of the possibility that they could harbor unique life forms that may have existed in isolation, locked under ice for millions of years.

Although it doesn't quite beat Lake Vostok's 240-kilometre by 60-kilometre size, the new lake is much closer to a research station. This would make it easier to approach and study in detail, says Martin Siegert of Imperial College London, a member of the team that located the putative lake.

The team's claim comes from satellite imagery, in which they identified grooves on the ice surface similar to those present above known subglacial lakes and channels.

Ribbon-shaped lake

"We've seen these strange, linear channels on the surface, and are inferring these are above massive, 1000-kilometer-long channels, and there's a relatively large subglacial lake there too," said Siegert.

He says the lake is around 100 kilometers long by 10 kilometers wide and is ribbon-shaped.

The long channels and canyons that seem to extend from the lake appear to spread for more than 1000 kilometers towards the eastern coast of Antarctica on Princess Elizabeth Land, between Vestfold Hills and the West Ice Shelf.

Two channels in particular seem to turn upwards into the ice and may convey water out of the West Ice Shelf into the ocean.

"It's the last un-researched part of Antarctica, so it's very exciting news, but it's still tentative pending full confirmation," says Bryn Hubbard of the University of Aberystwyth, UK.

Siegert says that a team of collaborators from China and the US have recently flown over the region and gathered ice penetrating radar data that will likely confirm the existence of the features under the ice.

"We're meeting in May to look at the data," he said. "It will be a very good test of our hypothesis about the lake and channels."

Pole of ignorance

If the existence of the lake and the channels is confirmed, as Siegert expects, he says it will be a major boost for Antarctic science and for research on subglacial lakes.

Just 100 kilometers from the nearest research base - a stone's throw on Antarctic scales - the new lake is far more accessible than others such as Lake Vostok, which is very remote.

That, says Siegert, should make it far easier to conduct vital investigations into the biology of the lake, to find out if it supports species unlike any others on the planet.

"It's really nice to see some new techniques for revealing the characteristics of the last 'pole of ignorance'," says Christine Dow, of the NASA Goddard Space Flight Center in the US.

 

"The potential discovery of large canyons and lakes could have a big impact on our understanding of tectonic and hydrological evolution in this part of the ice sheet."

Read more: Frozen Kingdom - The Lost World under Antarctica's Ice.