Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Antarctica’s Lake Vostok Has Two Distinct Parts, With Possibly Differing Ecosystems

08.07.2004


Deep in the Antarctic interior, buried under thousands of meters [more than two miles] of ice, lies Lake Vostok, the world’s largest subglacial lake. Scientists believe that the waters of Lake Vostok have not been disturbed for hundreds of thousands of years, and there are tantalizing clues that microbes may exist there that have been isolated for at least as long.

Now, the most comprehensive measurements of the lake--roughly the size of Lake Ontario in North America--indicate that it is divided into two distinct basins that may have different water chemistry and other characteristics. The findings have important implications for the diversity of any microbial life in Lake Vostok and for how scientists should study the lake’s various ecosystems, if an international scientific consensus is ever reached to explore the lake.

Lake Vostok is thought to be a very good terrestrial analogue to the conditions on Europa, a moon of Jupiter thought to hold a large liquid ocean far under its frozen surface. If microbial life can exist in Vostok, scientists have argued, then it also might thrive on Europa.



In a paper published June 19 in Geophysical Research Letters, a journal of the American Geophysical Union, scientists from the Lamont-Doherty Earth Observatory of Columbia University and the University of Tokyo describe the first-ever map of water-depth in Lake Vostok. The ice covering the lake is between 3,700 and 4,300 meters [12,000 and 14,000 feet] thick.

Russia has long maintained a research station at Lake Vostok, and Russian scientists have previously probed the lake with seismic waves. But these soundings produced measurements of the water depth only at isolated points. The new measurements are significant because they provide a comprehensive picture of the entire lakebed and indicate that, contrary what scientists had assumed, the bottom of the lake is not one continuous feature but contains a previously unknown northern sub-basin that is divided from the southern lakebed by a prominent ridge.

Michael Studinger of Lamont-Doherty, a principal author of the paper, said that the existence of two distinct regions with the lake would have significant implications for what sorts of ecosystems scientists should expect to find in the lake and how they should go about exploring them. "The ridge between the two basins will limit water exchange between the two systems," he said. "Consequently, the chemical and biological composition of these two ecosystems is likely to be different."

Using laser altimeter, ice-penetrating radar, and gravity measurements collected by aircraft flying over the lake, Studinger and Robin Bell of Lamont-Doherty and Anahita Tikku, then at the University of Tokyo, estimate that Lake Vostok contains roughly 5,400 cubic kilometers [1,300 cubic miles] of water.

Their measurements also indicate that the lake is divided into two distinct sub-basins, separated by a narrow ridge. The water over that ridge is relatively shallow (200 meters or 650 feet deep), as compared to the rest of the lake, where the water ranges from roughly 400 meters [1,300 feet] deep in the northern basin to 800 meters [2,600 feet] deep in the southern. The National Science Foundation (NSF) supported the research.

The arrangement of the two basins, their separation, and the characteristics of the meltwater may, the scientists conclude, all have implications for the circulation of water within the lake. It is possible, for example, that if the water in the lake were fresh, that meltwater in the northern basin would sink to the bottom of that basin, limiting the exchange of waters between the two basins. The meltwater in the adjacent basin likely would be different. The two lake basins, they argue, could therefore have very different bottoms. They also point out that the waters of the two basins may, as a result of the separation, have a very different chemical, and perhaps even biological, composition.

Scientists involved in deciding whether and how to proceed with an exploration of Lake Vostok have stressed that a great deal of technological development likely would have to take place before a device could be deployed to conduct contamination-free sampling. Currently, there is no scientific sampling of the lake being carried out. The new measurements also indicate that different strategies would probably have to be developed depending on the types of lake sediments targeted. The ultimate goal of any sampling strategy would be to obtain water and sediment samples from the lake bottom.

The Lake mapping would help to guide this scientific work. From the observed melting and freezing patterns of ice moving over Lake Vostok, it is evident that the northern basin would contain recent sediments of rock debris carried from land and deposited into the Lake, says Studinger. The southern basin, where water is frozen back to the base of the ice sheet, would not have these same recent deposits, but would more likely contain sediment deposits that recorded the environmental conditions before the ice sheet sealed off the Lake.

Harvey Leifert | American Geophysical Union
Further information:
http://www.agu.org
http://www.nsf.gov
http://www.ldeo.columbia.edu

More articles from Earth Sciences:

nachricht Devils Hole: Ancient Traces of Climate History
24.05.2017 | Universität Innsbruck

nachricht Supercomputing helps researchers understand Earth's interior
23.05.2017 | University of Illinois College of Liberal Arts & Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>