Isolated lakes found beneath Canadian ice sheet

Latest news

    The sun over a windswept ice fieldImage copyright Anja Rutishauser
    Image caption The lakes lie beneath the Devon ice cap in the Canadian Arctic

    Researchers have found lakes that may shed new light on icy worlds in our Solar System.

    High in the Canadian Arctic, two subglacial bodies of water have been spotted beneath over 500 metres of ice.

    The water has an estimated maximum temperature of -10.5C, and would need to be very salty to avoid freezing.

    There are thought to be similar cold, saline conditions in the subsurface ocean of Jupiter’s moon Europa, yet also the potential to host life.

    The findings, from a team led by the University of Alberta, have been published in Science Advances.

    Image copyright NASA/Anja Rutishauser
    Image caption At 1,200m – 1,700m above sea level, the lakes sit in long basins in a mountain range

    A Canadian first

    The two lakes appeared in a radar survey of the Devon Ice Cap, which sits on Devon Island, high in the Canadian Arctic.

    “I was super surprised, and a little bit puzzled,” Anja Rutishauser, the study’s lead author, said of the discovery. “I was definitely not looking for subglacial lakes.”

    Image copyright Gregory Ng

    Although water systems beneath large ice sheets are being found to be increasingly common, Devon Island’s ice cap was thought to be frozen to the bedrock beneath.

    These are the first subglacial lakes to be observed in the Canadian Arctic, and are estimated to cover areas of five and eight square kilometres respectively.

    “It’s an amazing finding, and one that I really wasn’t expecting from the geophysical survey of this small ice cap,” commented Prof Martin Siegert from Imperial College London, who was not involved in the study.

    “To my knowledge, this is a unique lake system. Of the [more than] 400 subglacial lakes in Antarctica, all of them are thought to comprise fresh water. Hence, whatever might be living in it may also be unique,” he added.

    Image copyright Tom Richter
    Image caption Surveys were conducted using radar antennae, mounted to the wings of an aircraft

    Life below zero

    The water in the lakes is estimated to be five times as salty as seawater, allowing its freezing point to be lowered below that of fresh water.

    Other subglacial lakes in Greenland and Antarctica are comprised of fresh water, generated by melting at the base of the ice. Geothermal heat rises from the underlying rock, and is insulated by the thick ice sheet above.

    The Canadian ice sheet is not thick enough to provide this insulation

    Salt-rich water has been studied beneath Taylor Glacier in Antarctica’s McMurdo Dry Valleys, but this is supplied by an ancient marine water basin.

    The mountainous location of these lakes places them above previous sea levels, and their salinity is derived from the high salt content of surrounding rock.

    “It is interesting,” notes Prof Jemma Wadham from the University of Bristol, “that the more places we look, the more subglacial lakes we find. Just like in non-glacial environments, there could be a huge diversity of lake types and life habitat conditions, and one size does not fit all.”

    Image copyright Anja Rutishauser
    Image caption Radar readings were taken across four years

    A pocket of Europa

    There are many answers researchers want to search for next. There may be an entire network of lakes in this region, beyond the two so far observed, and their size has yet to be determined.

    However the potential for these environments to host life is a pressing question, as they may represent a largely isolated microbial habitat.

    The study’s authors suggest the lakes may have been sealed off from surrounding environments for up to 120,000 years.

    “The probability of life to exist in these systems is high, though the modelled temperatures might suggest that the biological activity would be severely limited due to the low temperature,” Dr Alison Murray of Nevada’s Desert Research Institute told BBC News.

    Image copyright Gregory Ng
    Image caption View from the cockpit of a research flight

    They may also provide a window to life beyond Earth.

    Dr Claire Cousins from the University of St Andrews explains: “While the chemistry of these lakes may be somewhat different to ocean environments on icy moons such as Europa, their otherwise extreme conditions will help us understand the habitability of hypersaline sub-ice environments.”

    While further radar surveys are next on the list, Anja Rutishauser and her colleagues hope to be able to drill into the lakes’ waters one day, to better understand any ecosystem within.

    Such work could, Dr Murray says, provide “a key to understanding the life-supporting nature of such systems which may occur in the icy and ocean worlds of the Solar System and beyond.”

    View the original article: http://www.bbc.co.uk/news/science-environment-43701375

    http://www.bbc.co.uk/news/science-environment-43701375

    In the same category are

    Combating crime: Faith + Boxing = Meaning Share this with These are external links and will open in a new window Copy this link Read more about sharing. These are external links and will open ...
    Men steal cabinet of phones valued at £2,500 from Cardiff shop Media playback is unsupported on your device Media captionThe moment two men stole a cabinetPolice have released CCTV footage of two men who stole m...
    Anthony Joshua v Alexander Povetkin: Joshua changing approach Anthony Joshua unified the WBA, IBF and WBO world heavyweight titles with a unanimous points win over New Zealander Joseph Parker in March.Britain's ...
    Transgender inmate charged with sex offences at Wakefield jail Image copyright Google Image caption Karen White is accused of four counts of sexual touching at New Hall Prison, Wakefield A transgender prisoner...
    Cliff Richard: BBC bosses ‘should carry the can’ Media playback is unsupported on your device Media captionThe singer wins BBC privacy case at High Court but how did it get to thisSenior BBC manage...
    Paul Pogba: Man Utd boss Jose Mourinho hopes player ‘understands why he was good’ World Cup 2018: Paul Pogba's curling shot puts France 3-1 up against CroatiaManchester United manager Jose Mourinho says he hopes World Cup winner Pa...

    Leave a comment

    Your email address will not be published. Required fields are marked *

    This site uses Akismet to reduce spam. Learn how your comment data is processed.