An international team of geophysicists has discovered two hypersaline lakes beneath the Devon Ice Cap, one of the largest ice caps in the Canadian Arctic.
A cold and windy spring night on the vast landscape of the Devon Ice Cap where two subglacial lakes are lurking 1,805 to 2,460 feet (550-750 m) below the surface. Image credit: Anja Rutishauser.
While there are more than 400 known subglacial lakes in the world, concentrated primarily in Antarctica with a few in Greenland, the newly-discovered lakes are the first found in the Canadian Arctic.
And unlike all the others — which are believed to contain freshwater — these two appear to consist of extremely salty water.
They are thought to be the first isolated hypersaline subglacial lakes in the world, having no contact with an outside environment for thousands of years.
“If there is microbial life in these lakes, it has likely been under the ice for at least 120,000 years, so it likely evolved in isolation,” said lead author Anja Rutishauser, a Ph.D. student at the University of Alberta.
“If we can collect a sample of the water, we may determine whether microbial life exists, how it evolved, and how it continues to live in this cold environment with no connection to the atmosphere.”
Landsat image overlain with the location of the subglacial lakes and ice divides. Image credit: Rutishauser et al, doi: 10.1126/sciadv.aar4353.
In 2011, planetary researchers showed that Jupiter’s icy moon Europa, likely contains hypersaline lakes of liquid water within an ice shell that floats atop of a global ocean.
The newly-discovered Devon lakes are very similar to these potential lakes locked inside Europa’s icy shell.
“All subglacial lakes are good analogues for life beyond Earth, but the hypersaline nature of the Devon lakes makes them particularly tantalizing analogues for ice-covered moons in our Solar System,” the scientists said.
“By evaluating the airborne survey data and, eventually, samples from the lake, scientists can better prepare for NASA’s forthcoming Europa Clipper mission, which plans to deploy similar remote sensing techniques to characterize Europa’s ice shell,” said co-author Dr. Donald Blankenship, from the University of Texas Institute for Geophysics.
The discovery is reported in the journal Science Advances.
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Anja Rutishauser et al. 2018. Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, Canadian Arctic. Science Advances 4 (4): eaar4353; doi: 10.1126/sciadv.aar4353
