- Researchers find Antartic lake water will fizz like a soda
August 12, 2003
"Water released from Lake Vostok, deep beneath the south polar ice
sheet, could gush like a popped can of soda if not contained,
opening the lake to possible contamination and posing a potential
health hazard to NASA and university researchers.
A team of scientists that recently investigated the levels of
dissolved gases in the remote Antarctic lake found the
concentrations of gas in the lake water were much higher than
expected, measuring 2.65 quarts (2.5 liters) of nitrogen and oxygen
per 2.2 pounds (1 kilogram) of water. According to scientists, this
high ratio of gases trapped under the ice will cause a gas-
driven "fizz" when the water is released.
"Our research suggests that U.S. and Russian teams studying the lake
should be careful when drilling because high gas concentrations
could make the water unstable and potentially dangerous," said Dr.
Chris McKay of NASA's Ames Research Center in California's Silicon
Valley. McKay is lead author of a paper on the topic published in
the July issue of the 'Geophysical Research Letters' journal.
"We need to consider the implications of the supercharged water very
carefully before we enter this lake," said Dr. Peter Doran, a co-
author and associate professor of Earth and Environmental Sciences
at the University of Illinois at Chicago.
Lake Vostok is a rich research site for astrobiologists, because it
is thought to contain microorganisms living under its thick ice
cover, an environment that may be analogous to Jupiter's moon,
Europa. Europa contains vast oceans trapped under a thick layer of
ice. Russian teams are planning to drill into Lake Vostok's 2.48
mile (four kilometer) ice cover in the near future, and an
international plan calls for sample return in less than a decade.
An important implication of this finding is that scientists expect
oxygen levels in the lake water to be 50 times higher than the
oxygen levels in ordinary freshwater lakes on Earth. "Lake Vostok is
an extreme environment, one that is supersaturated with oxygen,"
noted McKay. "No other natural lake environment on Earth has this
The research also suggests that organisms living in Lake Vostok may
have had to evolve special adaptions, such as high concentrations of
protective enzymes, in order to survive the lake's oxygen-rich
environment, the researchers say. Such defense mechanisms may also
protect life in Lake Vostok from oxygen radicals, the dangerous
byproducts of oxygen breakdown that cause cell and DNA damage. This
process may be similar to that of organisms that scientists theorize
may once have lived on Europa, whose ice layer and atmosphere are
thought to contain radiation-produced radicals and oxygen.
"We expect to find that the organisms in Lake Vostok are capable of
overcoming very high oxygen stress," said co-author Dr. John Priscu,
a geo-biologist at Montana State University in Bozeman. Priscu heads
an international group of researchers that will deploy a remote
observatory at Lake Vostok within three years and return samples
within 10 years.
The team also determined the ratios of gases in the lake. The
scientists discovered that the air-gas mixture there, besides
dissolving in the water, also is trapped in a type of structure
called a 'clathrate'. In clathrate structures, gases are enclosed in
an icy cage and look like packed snow. These structures form at the
high pressure depths of Lake Vostok and would be unstable if brought
to the surface.
Lake Vostok is located 2.48 miles (four kilometers) beneath the East
Antarctic Ice Sheet. The lake, and more than 70 other lakes deep
beneath the polar plateau, are part of a large, sub-glacial
environment that has been isolated from the atmosphere since
Antarctica became covered with ice more than 15 million years ago.
Scientists theorize that Lake Vostok probably existed before
Antarctica became ice covered, and may contain evidence of
conditions on the continent when the local climate was subtropical.
For images and further information about plans to return research
samples from Lake Vostok, go to:
NASA Ames Research Center
Note that the microbial biosphere would have been conductive and the
hydrates insulative when Antarctica wasn't snow covered, and when it
uncovers of ice, over longer timescales, the biosphere can come alive
with its electrical dynamics there. I am not related to Peter.
It's all biological and electrical.