Fun fact: Antarctica is the world’s largest desert. And, a new find under the McMurdo Dry Valleys could have implications for life on Mars.
A team of researchers discovered a vast network of salty lakes deep beneath Antarctica. The discovery “provides compelling evidence that the underground lakes and brine-saturated sediments may support subsurface microbial ecosystems.”
Finding this vast underground saltwater network will help researchers better understand how Antarctica is responding to rising temperatures around the world. It will also help them better understand glacial dynamics.
“It may change the way people think about the coastal margins of Antarctica,” Jill Mikucki, a University of Tennessee microbiology assistant professor, said. “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 underground saltwater is also responsible for one of the most incredible sights in Antarctica – the Blood Falls.
To spot the salty water, Mikucki and the research team used an airborne electromagnetic mapping sensor system called SkyTEM. Check out the system in the image below.
SkyTEM allowed the researchers to scan a large area of the McMurdo Dry Valleys. They found brines form huge aquifers below glaciers and even the permanently frozen soil.
SkyTEM lead Esben Auken described what it was like working in Antarctica. “Antarctica is by far the most challenging place we have been,” Auken said. “It was all worth it when we saw the raw data as it was offloaded from the helicopter; it clearly showed we were on to some extraordinary results which no one had been able to produce before.”
What’s the connection to Mars?
Scientists like to compare the extremely dry environment throughout the McMurdo Dry Valleys with Mars. Finding the underground network of water gives scientists hope that something similar is possible on Mars.
The subpermafrost brines in the MDV provide an important terrestrial analogue for future exploration of a subsurface Martian habitat. Briny groundwater has been suggested as supporting a deep biosphere on Mars. Recent mineralogical analysis of Gale Crater supports the notion that previous fluvio-lacustrine environments may have hosted chemoautotrophic microorganisms. On Mars, as we observe in the dry valleys, connectivity between lacustrine systems and groundwater would be important in sustaining ecosystems through drastic climate change, such as lake dry-down events.
SkyTEM image credit: J. Mikucki
Blood Falls image credit: Hassan Basagic/National Science Foundation
McMurdo Dry Valleys image credit: Peter West/National Science Foundation