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Science

Antarctic Lake Actually Two in One 332

Posted by michael from the double-your-pleasure dept.
Scoria writes "USA Today reports: Scientists have discovered that Lake Vostok, a liquid freshwater lake which has been isolated from the world beneath 4 km of ice for approximately 500,000 years, contains two separate basins. They believe that the basins, which are divided by a ridge that limits water exchange, may host individual ecosystems that are home to ancient microbes."
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Antarctic Lake Actually Two in One More

Antarctic Lake Actually Two in One

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  • Maybe (Score:5, Funny)

    by wideBlueSkies ( 618979 ) * on Sunday July 11, 2004 @06:57PM (#9670230) Journal
    It's really one giant organism in the process of dividing....

    wbs.

    • Re:Maybe (Score:5, Funny)

      by ThisIsFred ( 705426 ) on Sunday July 11, 2004 @09:55PM (#9671232) Journal
      That would be so sweet. I'd pay good money to see the Antarctic mega-organism have it out with that monster fungus in Oregon.

  • Define "Ancient" (Score:5, Insightful)

    by toxic666 ( 529648 ) on Sunday July 11, 2004 @07:08PM (#9670293)
    Is that in human terms (thousands of years) or microbe terms (billions of years)?

    All I got reading the article was that the fresh water has been isolated for 500,000 years and the ridge that separates them limits water exchange, resulting in isolated environments in which two different biomes may have formed.

    Isn't the wording of the post a bit along the lines of NASA polit-speak? Unique environments, geothermal heating -- voila NEW LIFE FORMS! Let's submit a budget request for a probe to an ice world to look for life!
    • Half a million years is pretty long in this context, especially for organisms that can potentially reproduce quite frequently or have dozens if not hundreds of generations per year (even thousands).

      This has huge scientific potential but not for the reasons most slashdotters are positing. For scientists studying the genome, it's largely about calibrating their evolutionary rulers, and less about super alien organisms.

      Unlike large animals which can be geographically isolated and evolve undisturbed, free living microbes (as opposed to those that need a specific animal or plant host) probably range freely and easily by the fact that they carry easily on the wind or the skin of migrating animals or move with the major currents that circulate the globe. Even if only one microbe makes it to a local it can begin to reproduce, since it doesn't rely on sexual replication, it isn't inconvenienced by having to find a mate also flung into some far foreign environment.

      All of this is to say, these microbes will have had what in microbe evolution is something fairly rare, an environment completely free from competition from other global varieties seeking to fill the same ecological niche. I doubt they will have mutated far from their other global cousins, but the rate of change of DNA is probably what really matters to scientists, as for long time periods we would only be making guesses about genomic drift in microbes.

      Given the extreme environment these microbes inhabit, there may also be some extreamophile surprises for cold adaptation.

      Another possible study will be how quickly the isolated community looses defenses to protozoa and other microscopic predators that may not now be present in their extremely isolated pocket of liquid water beneath the ice.

      • Re:Half a Million is LONG for a microbe. (Score:5, Interesting)

        by toxic666 ( 529648 ) on Sunday July 11, 2004 @08:26PM (#9670723)
        I fully agree with your comments. The oil fields have microbes that are hundreds of millions of years old, uniquely evolved to their environment and may have evolved from the microbes that were in the original, surficial organic muck.

        My original point was that /. editors tend to have a point of view that coincides with NASA funding requests based upon a search for life as justification. Describing a 500,000 year-old environment as "ancient" suggests something unique.
      • I'm not excited about the microbes. The size of the lakes suggest some pretty bizarre fish could be found in the lake. Strange alien-looking freaky fish are found in other trenches (read: high pressure), and this place has been completely isolated. Are we too crazy to expect creatures bigger than people deep down there?

        The temperature might be a problem though.

        And so would our equipment contaminating the lake and killing off the fish, so we'd only find bodies of the awesome creatures.

        • Re:Half a Million is LONG for a microbe. (Score:4, Insightful)

          by CreatureComfort ( 741652 ) * on Monday July 12, 2004 @08:09AM (#9673732)

          Actually creatures as large as humans are probably impossible in this environment. To have large animals, you need a relatively large supply of smaller animals/plants that reproduce quickly enough to be eaten and keep the large animal supplied with food/energy. (If you posit smaller animals, the same applies all the way down the food chain until you get to plants.) To have a large supply of plant life to feed the rest of the food chain, there has to be a large energy input into the system. For most of the earth this source is the sun. For Lake Vostok, buried under 4 miles of ice, I doubt that much sunlight ever makes it down there. There may be geothermal vents, which could introduce a lot of energy, but even so they would be very localized, and not suitable for powering a large food chain that would include large animals.

    • Re:Define "Ancient" (Score:4, Interesting)

      by dragons_flight ( 515217 ) on Sunday July 11, 2004 @10:11PM (#9671312) Homepage
      Actually 500,000 years maybe a significant understatement. Antarctica has been continuously glaciated for the last ~40 million years. We know that the lake is at least 500,000 years old because that is roughly the age of the ice directly above it. However, as with all glaciers, the ice slowly creeps from the central domes where snow accumulates out the ocean where icebergs form and the edges melt. Hence, it is pretty certain that the ice above Vostok today is not the ice that was there when the lake first formed.

      This opens the possibility that the lake may have existed continuously under the ice for 20 or 30 million years. Till we crack her open and look inside it will be hard to say.

  • Does anyone else find it amazing... (Score:5, Interesting)

    by Anonymous Coward on Sunday July 11, 2004 @07:13PM (#9670326)
    That a liquid freshwater lake can survive that far underneath Antarctica? I would've imagined it to have either frozen, or at least be saltwater, which would enable it to stay liquid in low temperatures. If geothermal heat is responsible, then why isn't the ice around it melting, or is it just one of those finely balanced peculiarities of nature?

    • Re:Does anyone else find it amazing... (Score:4, Interesting)

      by BlueJay465 ( 216717 ) on Sunday July 11, 2004 @07:25PM (#9670405)
      As for the geothermal theory, if it was the cause of this under-ice lake, then the convection current would have eventually blended the two basins.

      I remain skeptical.
      • As for the geothermal theory, if it was the cause of this under-ice lake, then the convection current would have eventually blended the two basins.

        Geothermal heat is NOT uniform. That's why you have Yellowstone with its geysers, other places have volcanoes and in some nothing important. An area the size of a continent will have many different hot spots and cold spots, separated by dozens or hundreds of kilometers. There could be hundreds of "little" lakes :)

    • Perhaps it could be down to the pressure of 4km of ice causing sufficient heating at lower levels for freshwater to be liquid.

      But I'm no geologist (or physicist) ;)

      • Re:Maybe its pressure? (Score:2, Informative)

        by BearJ ( 783382 )
        Maybe it's the lake effect (at least I think that's what it's called). Basically, the lake freezes from the top down. But ice expands when it freezes, so there comes a point where the ice at the top of the lake is too thick, so the water at the bottom can't form into ice as it can't expand.

        Or so I recall from a distant high school class...

        • Re:Maybe its pressure? (Score:4, Informative)

          by another_henry ( 570767 ) <slashdot&henryhallam,cjb,net> on Sunday July 11, 2004 @07:51PM (#9670563) Homepage
          I don't think that's necessarily true... This explanation [madsci.org] makes sense - the water does expand at freezing point, but contracts again as it continues to get colder. Unless it's a particularly sunny part of the antarctic, I think it would be cold enough that the whole lot could freeze. I'd put my bets on geothermal.

          • Re:Maybe its pressure? (Score:3, Insightful)

            by Anonymous Coward
            The water may contract as it gets colder, but because it is under so much pressure from 2 miles of ice above it, the water freezes at a lower temperature. As pressure increases, the freezing point of water decreases. I just don't know how much pressure would be needed to keep the water a liquid at whatever the temperature is at that depth. It is most likely a combination of geothermal heat and the effects of pressure on the freezing point of water.

      • Re:Maybe its pressure? (Score:3, Interesting)

        by Aphrika ( 756248 )
        It appears that pressure does play a part. There's some good information here [wikipedia.org] which also points out that pressure has had the effect of super-saturating the water with oxygen.

        I remember reading a while back (I think it was in Wired?) that they had problems boring through the ice as the pressure closed the hole. The initial plan was to pump the hole full of oil to keep it open, although this plan was scrapped because of the environmental implications. Last I heard, they were toying with the idea of sealing

      • Re:Maybe its pressure? (Score:3, Interesting)

        by kevlar ( 13509 )
        I think that might be possible. The pressure of metal ice skates on the surface of the ice produces a thin layer of frozen temperature water. I guess if you have enough pressure , you could produce an entire lake of very cold, very pressurized water.

    • Not really (Score:5, Informative)

      by i8a4re ( 594587 ) on Sunday July 11, 2004 @07:49PM (#9670552)

      The fact that it isn't saltwater isn't very surprising at all. Almost all glacial ice is freshwater. When saltwater is frozen for a very long time, the salt actually works its way out of the ice, leaving fresh water ice. Since the lake is in the middle of one huge, relatively old piece of ice it is not surprising at all that it is not salt water.

      Also, it is not too peculiar that all the ice isn't melting. If you have a few small heat sources in the middle of several kilometers of ice, you'd expect it to melt a small area of ice around it. Since the heat requirements grows exponentially to melt a larger volume of ice and there are several kilometers of ice to melt, it would take a very large heat source to melt enough ice to either melt up to the surface or to the ocean.

      <Bitching>I love how I press submit and get an error. I try it again and it tells me that I have to wait xx seconds before posting again. If I couldn't post due to an error, why do I have to wait to try again?</Bitching>

    • Yep, it looks like we're about to disrupt the Atlanteans.

      Poor saps thought they could survive isolated from the world under a two mile sheet of ice. Hah!

      Just imagine all those wonderful ice castles buried under tons of ice!!!

    • From the article:

      Geothermal heat, seeping through the rocks below the lake, keeps it above the melting point of ice.

    • Re:Does anyone else find it amazing... (Score:5, Informative)

      by dragons_flight ( 515217 ) on Sunday July 11, 2004 @09:35PM (#9671124) Homepage
      Your guess is basically right. The lakes under Antarctica exist because of a balance between the slow trickle of geothermal heat and the insulating qualities of kilometers of ice.

      You may be aware that as one digs down into the Earth it starts to get hotter. This is because everywhere on the Earth there is a slow trickle of ambient geothermal energy being dissipated from the hot core out to the much cooler surface. This should not be mistaken for much more intense geothermal phenomena like volcanos and hot springs as they have nothing to do with most subglacial lakes.

      Since everywhere on Earth a little bit of geothermal heat is being released (roughly 1% of the power/area of sunshine) this includes the bottoms of glaciers. This causes the bottoms of ice sheets to always be warmer than their tops. For most glaciers this is only a few degrees, and no cares, but as the ice sheet grows, the ice can eventually become so thick that it can't dissipate the geothermal energy effectively and the bottom will melt. This is responsible for the majority of subglacial Antarctic lakes.
  • Just in time for the premier of Stargate:Atlantis. Beautiful. What a promo.

  • I'm looking forward to... (Score:5, Funny)

    by Scoria ( 264473 ) <slashmail AT initialized DOT org> on Sunday July 11, 2004 @07:17PM (#9670346) Homepage
    ... Vostok bottled water, a pleasant alternative to Evian. ;-)

  • Europa testing (Score:5, Insightful)

    by Killshot ( 724273 ) on Sunday July 11, 2004 @07:17PM (#9670349) Homepage
    They should use this lake to test ideas for drilling into the ice of Europa.

    • Re:Europa testing (Score:3, Interesting)

      by Pinkfud ( 781828 )
      That's already in the works. Don't you follow the Science Channel? :) Seriously, they are planning to test methods of drilling on Europa there. The problem is to get it done without introducing any microbes into the water, because then their findings would be contaminated and useless. So they're working very carefully on the design of the devices they're going to use.

  • I found a picture... (Score:3, Funny)

    by squidfrog ( 765515 ) on Sunday July 11, 2004 @07:31PM (#9670448) Homepage
    ...of what scientists believe the life may look like [giantmicrobes.com] down there.

  • Ice vs Deep Sea (Score:3, Interesting)

    by powerpuffgirls ( 758362 ) on Sunday July 11, 2004 @07:32PM (#9670449)
    Is it easier to deal with ice than venturing into deep sea? I have read that many interesting creatures are in deep sea where we cannot quite reach.

    Either way, I'm equally excited to know that something else we don't know might be within reach, pretty much like others being excited by aliens.
    • I have read that many interesting creatures are in deep sea where we cannot quite reach.

      Humans have been at the bottom of the Marianas Trench, which is the deepest part of the ocean. Exploration of the sea is more of a political and economic problem than a technical one.

  • RE:Antarctic Lake Actually Two in One (Score:2, Funny)

    by Anonymous Coward
    Bottle it! Return with us now to those thrilling days of yesteryear. Let's siphon some off into lake Erie and see what happens..where'd I leave that roach..

  • To quell some of the speculation (Score:5, Informative)

    by saforrest ( 184929 ) on Sunday July 11, 2004 @08:14PM (#9670665) Journal
    It seems, at least according to this Wikipedia entry, that there is not yet an scientific consensus on why Lake Vostok remains liquid.

    Wikipedia: Lake Vostok [wikipedia.org].

    • Re:To quell some of the speculation (Score:4, Informative)

      by Anonymous Coward on Sunday July 11, 2004 @09:55PM (#9671224)
      I suggest that the Wikipedia entry is misleading, if not incorrect.

      The lake remains liquid for two reasons:

      (1) geothermal heat (flux): using a conservative estimate of the geothermal heat flux of the East Antarctic (which has never been measured directly), say 50 mW/m^2, the measured ice thickness in the area (via radio-echo sounding, or active seimic) of ~ 4000 m^2, thermal conductivity of ice ~2.3 W/m K, and mean annual surface temperautre of ~ -55C suggests that the base of the ice sheet should be at the melting point. Ah, the heat equation in 1-D!

      (2) freezing point depression changes the phase transition at Vostok from 0C to ~ -3C. A small but significant correction. Other corrections involve advection in the ice column due to ice flow, the ~110 m of firn overlying the glacial ice, etc. None of these corrections change the conclusion derived from (1), above.

      The ice adjacent to the lake is also at the melting point, as are many areas in both East and West Antarctica. Whether the melt water collects into a subglacial lake is determined by the local hydraulic gradient. In many places, basal melt water flows along the gradient and refreezes where the ice thickness decreses. In other place, water collects into lakes. There are ~70 subglacial lakes in the Antarctic, although none nearly as large as Lake Vostok.

      A temperature change 5000 years ago will have essentially no influence on the basal ice temperature at Vostok, in contrast to what Wikipedia suggests. The thermal diffusivity is far too slow, and the accumulation rate at the surface is also too small to generate rapid enough thermal vertical advecion.

      Cheers,
      tom
  • What needs the press now is that there you could find plants, fishes, even animals. Is a shame that the time frame is not enough for dinosaurs, else we could have a great fun reading reports of a Lost World'-alike life from down there.

    Probably this have not scientific basis, but i suspect to find such kinds of approachs to what is hidden there in internet in the next few days.

    • The lake is believed to have formed when the bottom of the glacier melted, so the only life that could be there are microbes that could exist in the dirt or in the ice before that happened.

  • 2 Miles of Ice? (Score:4, Interesting)

    by kevlar ( 13509 ) on Sunday July 11, 2004 @09:18PM (#9671028)
    If there is 2 Miles of Ice below Antarctica, does that mean that the surface is at 10,000+ ft?

  • Gotcha!! (Score:4, Funny)

    by mbstone ( 457308 ) on Sunday July 11, 2004 @09:27PM (#9671065)
    Y'all got taken in. Obviously this "news" story is movie hype for Alien vs. Predator [avp-movie.com] (8/15 release). If you had gone to the movies this weekend you would have seen the trailer (scientists find pyramid buried 1000s of feet under Antarctic ice cap, it contains Alien-style aliens which emerge from their pods and eat you.

  • Gulag Ice Lens (Score:5, Interesting)

    by handy_vandal ( 606174 ) on Sunday July 11, 2004 @11:06PM (#9671679) Homepage Journal
    From the preface to The Gulag Archipelago by Aleksandr Solzhensitsyn:
    "In 1949 some friends and I came upon a noteworthy news item in Nature, a magazine of the Academy of Sciences. It reported in tiny type that in the course of excavations on the Kolyma River a subterranean ice lens had been discovered which was actually a frozen stream -- and in it were found frozen specimens of prehistoric fauna some tens of thousands of years old. Whether fish or salamander, these were preserved in so fresh a state, the scientific correspondent reported, that those present immediately broke open the ice encasing the specimens and devoured them
    with relish on the spot."
    Links [google.com]

  • Endangered species? (Score:3, Funny)

    by mveloso ( 325617 ) on Monday July 12, 2004 @12:06AM (#9671951)
    Why aren't environmentalists up-in-arms about this type of arctic drilling? This is a pure, untouched ecosystem that's going to be contaminated by people for no real reason except for curiosity.

    Don't those 500,000 year old microbes have just as many rights as the spotted owl, salmon, and those lizards in the West somewhere?

    Stop this microbe genocide now, and prevent all drilling - whether it's for commerce (oil) or science!

  • Going there soon (Score:4, Interesting)

    by dargaud ( 518470 ) <slashdot2@gd a r gaud.net> on Monday July 12, 2004 @02:34AM (#9672490) Homepage
    Here's a radar map of Lake Vostok [gdargaud.net] showing the Vostok russian Station, along with other radar maps of Antarctica [gdargaud.net].

    I couldn't find an easier job, so I just signed up for the first winter over at Dome C [gdargaud.net] on the high Antarctic Plateau, only 550km from Vostok. On the program of the fun will be: reaching ground level with a 3200m ice core (they are almost there), temperatures of -84C in winter and lots more. Unlike Vostok, Dome C doesn't have a lake underneath. I'll try to keep my site updated.

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