Lakes discovered beneath Greenland ice sheet

From the University of Cambridge

The subglacial lakes are the first to be identified in Greenland

The study, published in Geophysical Research Letters, discovered two subglacial lakes 800 metres below the Greenland Ice Sheet. The two lakes are each roughly 8-10 km2, and at one point may have been up to three times larger than their current size.

Subglacial lakes are likely to influence the flow of the ice sheet, impacting global sea level change. The discovery of the lakes in Greenland will also help researchers to understand how the ice will respond to changing environmental conditions.

The study, conducted at the Scott Polar Research Institute (SPRI) at the University of Cambridge, used airborne radar measurements to reveal the lakes underneath the ice sheet.

Lead author Dr Steven Palmer, formerly of SPRI and now at the University of Exeter, stated: “Our results show that subglacial lakes exist in Greenland, and that they form an important part of the ice sheet’s plumbing system. Because the way in which water moves beneath ice sheets strongly affects ice flow speeds, improved understanding of these lakes will allow us to predict more accurately how the ice sheet will respond to anticipated future warming.”

The lakes are unusual compared with those detected beneath Antarctic ice sheets, suggesting that they formed in a different manner. The researchers propose that, unlike in Antarctica where surface temperatures remain below freezing all year round, the newly discovered lakes are most likely fed by melting surface water draining through cracks in the ice. A surface lake situated nearby may also replenish the subglacial lakes during warm summers.

This means that the lakes are part of an open system and are connected to the surface, which is different from Antarctic lakes that are most often isolated ecosystems.

While nearly 400 lakes have been detected beneath the Antarctic ice sheets, these are the first to be identified in Greenland. The apparent absence of lakes in Greenland had previously been explained by the fact that steeper ice surface in Greenland leads to any water below the ice being ‘squeezed out’ to the margin.

The ice in Greenland is also thinner than that in Antarctica, resulting in colder temperatures at the base of the ice sheet. This means that any lakes that may have previously existed would have frozen relatively quickly. The thicker Antarctic ice can act like an insulating blanket, preventing the freezing of water trapped underneath the surface.

As many surface melt-water lakes form each summer around the Greenland ice sheet, the possibility exists that similar subglacial lakes may be found elsewhere in Greenland. The way in which water flows beneath the ice sheet strongly influences the speed of ice flow, so the existence of other lakes will have implications for the future of the ice sheet.

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Steven J. Palmer, Julian A. Dowdeswell, Poul Christoffersen, Duncan A. Young, Donald D. Blankenship, Jamin S. Greenbaum, Toby Benham, Jonathan Bamber, Martin J. Siegert. Greenland subglacial lakes detected by radar. Geophysical Research Letters, 2013; DOI: 10.1002/2013GL058383

Abstract

Subglacial lakes are an established and important component of the basal hydrological system of the Antarctic ice sheets, but none have been reported from Greenland. Here, we present airborne radio echo-sounding (RES) measurements that provide the first clear evidence for the existence of subglacial lakes in Greenland. Two lakes, with areas ~8 and ~10 km2, are found in the northwest sector of the ice sheet, ~40 km from the ice margin, and below 757 and 809 m of ice, respectively. The setting of the Greenland lakes differs from those of Antarctic subglacial lakes, being beneath relatively thin and cold ice, pointing to a fundamental difference in their nature and genesis. Possibilities that the lakes consist of either ancient saline water in a closed system or are part of a fresh, modern open hydrological system are discussed, with the latter interpretation considered more likely.

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45 thoughts on “Lakes discovered beneath Greenland ice sheet

  1. I’m confused. The science is settled yet something new has been discovered? Clearly the only way to clear this up is with more research funding.

  2. “Subglacial lakes are likely to influence the flow of the ice sheet, impacting global sea level change. The discovery of the lakes in Greenland will also help researchers to understand how the ice will respond to changing environmental conditions.”
    =============
    They just discovered the lakes, and have determined they are ” likely to influence the flow of the ice sheet”.
    It couldn’t be the reverse could it ?, the weight of ice affects the lakes ?, or even tectonics ?

    Ah, nobody is even watching these press releases anyway, they can say anything with no fear of it being fact checked :)

  3. “Subglacial lakes are likely to influence the flow of the ice sheet, impacting global sea level change. The discovery of the lakes in Greenland will also help researchers to understand how the ice will respond to changing environmental conditions.”

    Discovering the lakes now does not mean they have not been there for centuries or millenia. If the lakes have been there for a long time then they have been influencing the flow of the ice sheet for a long time and will have no added impact to sea levels. The conjecture is stupefying

  4. The two lakes are each roughly 8-10 km2, and at one point may have been up to three times larger than their current size.

    Another nail in the coffin of “unprecedented” current warming.

  5. Discovered? Known by historians interested in old maps. Also written about in at least two sources from 12th-14th century. What scientist discovering the lakes don’t seem to know is that the ice above periodically was open, according to one of the sources, before 1341 and that the freezing of thick ice above came very quickly. Same freezing as made ‘Garden under Sandet’ in a few years going from a wealthy farm with lots of animals (stables in building show that) to an under thick ice long forgotten civilisation. Please read: Garden under Sandet, archeurope.com

    For more information re. the lakes please look in Grönländske Middelser for Historic as well as Geologic information re. 1060. It’s linked to an information re. a King’s son and some priests who were to use the way between the islands which many today belive is one island – Greenland.

  6. Thermal submarine heating doesn’t seem to affect them. Under the sea ice in antarctica, there is coral growing in some areas under the ice. Must be near warm vents or has evolved in low water temps. So what is their problem. We know there are thousands of submarine volcanoes and deep ocean vents with sea life and plants growing there existing on chemosynthesis in darkness. This is believed to mimic the first forms of sea life that convert energy from chemicals not sunlight or oxygen.

  7. “Subglacial lakes are likely to influence the flow of the ice sheet, impacting global sea level change.”

    Bullshirt.

  8. “The two lakes are each roughly 8-10 km2, and at one point may have been up to three times larger than their current size.”

    How was it determined that the lakes were previously larger? The “may have” seems to mean that they are guessing.

    “The discovery of the lakes in Greenland will also help researchers to understand how the ice will respond to changing environmental conditions.”

    Apparently their guess is that global warming is reducing the size of the lakes. Thus these lakes are affecting the flow rate of the ice sheet less and less.

    SR

  9. While surface melt can occur during relatively short periods on ice sheets to depths of several cm (due to a combination of solar input and air heat transfer), large thicknesses of ice with year round average temperatures far below zero are a different animal at large depths. While melting ice flowing into holes can make the penetration deeper, this only occurs when the average surface temperature year round is not too far below zero, so the deeper ice is not too cold. This only occurs at the edges of near temperate glaciers. The large specific heat and heat of fusion/melting require a very large average energy input.

    To give an example, it is the Error Function that defines average heat penetration for a give jump in average temperature at the surface. The Greenland ice sheet is far below zero on average (typical -20 C), even though it gets above zero at the surface some places for a few weeks or months. If the yearly AVERAGE temperature suddenly jumped 5 degrees C from -20 C to -15 C, the time it would take for a layer 800 m deep to heat just 0.5 C warmer than before the jump, due to thermal conduction from the surface, would be about 100,000 years. This increase of 0.5 degree C would not melt ice that is near -20 C to start with.

    It is clear that subsurface heating from the hot interior of the earth makes the pools, but the cooling from ice above is in local balance with the underside heating or the pools would grow. Heating of modest amounts on the top of the cold ice would not affect the ice near the pools for many thousands of years.

  10. What another unknown?
    But they were so certain that floodagedon was gonna happen.
    Whats next? Admissions that reality is far more various and wonderful that computer models?

  11. More data to mess with, that’s all it is useful for to the alarmists. They’ll soon be claiming that THIS TIME we have something to worry about because they’ve “discovered” another tipping point – you know, when the lakes will expand to such a size due to warming and melting ice, that they’ll sloop the rest of the ice right down to the sea. Something like that. Maybe they shouldn’t have suggested that the lakes might have once been larger, they might have wrecked an opportunity, there.

  12. As discovered earlier in the year that Greenland had “The hidden canyon is up to half a mile deep, six miles wide and stretches for 466 miles beneath the country’s giant ice sheet.
    It is thought to have been carved out by a meandering river more than four million years ago – at a time before ice covered the area and humans were just beginning to evolve from primates. ”

    http://www.telegraph.co.uk/news/worldnews/europe/greenland/10275580/Canyon-longer-than-Grand-Canyon-found-buried-under-Greenland-ice-sheet.html

    Up to half a mile deep, filled with ice. That would be quite a weight of ice in that bowl 6 miles wide and 466 miles long. What pressure is the ice at the bottom of this canyon at with half mile of ice sat on it? Enough to melt the ice?

  13. 10 percent of the world’s unproven oil reserves and 30 percent of its gas reserves are thought to also be under that ice and China was trying to lay claim to it. But Greenland has become Greenpeace friendly now and that’s been put on ice?

    http://www.icenews.is/2011/11/14/greenland-open-to-china-interest/

    China has laid claim to most of the South China Sea and actually just created an air defense zone over a large chunk of international waters. They also have a dispute going on in formerly international waters farther south.

  14. Thought the phrase “…respond to changing environmental conditions” was interesting. Not long ago it would have read “…respond to Climate Change”..

  15. the newly discovered lakes are most likely fed by melting surface water draining through cracks in the ice. A surface lake situated nearby may also replenish the subglacial lakes during warm summers.”
    If correct, what does this do to the trapped isotope signatures on which we all rely?
    Smear them? Contaminate them?

  16. greenland ice sheet sits in a deep depression in the crust caused by to weight of the ice thus limitig any outward movement. These lakes have been there for thousands of years and have caused no movement to date.

  17. Out of sheer boredom I just looked for the state of “greenland is melting faster than ever” alarmism, and landed on something called the WaPo’s “Wonkblog” which applied the newfangled Cook method; instead of looking at data they decided to just ask 90 alarmists for their estimates, and lo and behold, we’ll get a meter or more til 2100, say those alarmists, so…

    …Warmism is reduced to wankery, warmists ask each other how bad it can get; it’s the new gold standard of climate science. Maybe they can also pay each other next for it and leave out the taxpayer and warmism can then build the new shiny city of a warmist future on the yawning heights of modeling all on its own; and take the wonkers of the world with them.

  18. “Because the way in which water moves beneath ice sheets strongly affects ice flow speeds, improved understanding of these lakes will allow us to predict more accurately how the ice sheet will respond to anticipated future warming.”

    And there it is; the requisite money-grubbing anti-science quote. They don’t have a clue what effect if any, these recently-discovered lakes might have, but the hope appears to be that they’ve discovered some sort of positive feedback, or Trenberth’s infamous “arctic death spiral”.

  19. “…are likely…predict… suggesting…most likely…may also… possibility exists… may be… implications…possibilities… interpretation… more likely..”

  20. Leonard Weinstein says:
    November 27, 2013 at 7:24 pm

    ____________
    Thanks for the very interesting comment.

  21. In a sane world free from climatism, a discovery like this would simply be allowed to stand alone, without the pasted-on “meaning” of the discovery, and baseless assumptions. Someday.

  22. What interests me is if there is life forms down there, and what manner of life. If there is life, it makes a great case for life under the ice sheets of Europa.

  23. The researchers propose that, unlike in Antarctica where surface temperatures remain below freezing all year round, the newly discovered lakes are most likely fed by melting surface water draining through cracks in the ice. A surface lake situated nearby may also replenish the subglacial lakes during warm summers.

    Surface soot might help a little or a lot.

    http://wattsupwiththat.com/2010/11/03/greenland-ground-zero-for-global-soot-warming/

    http://news.discovery.com/earth/global-warming/soot-speeding-greenlands-ice-melt-121207.htm

    http://www.theguardian.com/environment/2012/dec/07/greenland-ice-melting-arctic-wildfires

    http://e360.yale.edu/slideshow/documenting_earths_disappearing_glaciers/145/1/

  24. The apparent absence of lakes in Greenland had previously been explained by the fact that steeper ice surface in Greenland leads to any water below the ice being ‘squeezed out’ to the margin.

    So they decided to guess. Is the Greenland ice sheet melt scenarios settled science yet?

  25. Armagh Observatory says:
    November 27, 2013 at 4:46 pm

    Would a geothermal hot spot beneath the ice sheet result in a similar sub-glacial lake?

    I do not have the fainest idea. I gather there are hundreds of hot springs to bath in. See these photos of Erik’s grandkids having a frolic in the warm pools on the fringes of Greenland. Apparently these aprings are not a result of volcanic activity (according to the image page), but by water being “heated by deep layers in the earth’s crust rubbing against each other.”

    Abstract – 2001
    High Geothermal Heat Flow, Basal Melt, and the Origin of Rapid Ice Flow in Central Greenland
    Age-depth relations from internal layering reveal a large region of rapid basal melting in Greenland. Melt is localized at the onset of rapid ice flow in the large ice stream that drains north off the summit dome and other areas in the northeast quadrant of the ice sheet. Locally, high melt rates indicate geothermal fluxes 15 to 30 times continental background. The southern limit of melt coincides with magnetic anomalies and topography that suggest a volcanic origin.

    http://www.sciencemag.org/content/294/5550/2338.short

    —————
    Abstract – 2005
    Relation of measured basal temperatures and the spatial distribution of the geothermal heat flux for the Greenland ice sheet

    http://www.ingentaconnect.com/content/igsoc/agl/2005/00000042/00000001/art00062

  26. “The ice in Greenland is also thinner than that in Antarctica, resulting in colder temperatures at the base of the ice sheet. ”

    I find this surprising. Antarctica ice thickness is generally >2km thick while Greenland ice thickness is generally >1km. Is there really a difference in insulation between 1km of ice and 2 ?
    What’s Up With That?

  27. Why don’t these Calamastrologists just say we discovered a couple of sub-glacial lakes and leave it at that. How do we know these lakes weren’t there in 1900, 1925, 1940 1,000 years ago, 2,000 years ago? Oh, we do know because they say it might have been larger in the past!!! What does this tell me about the future of the ice sheet? What do they know? Is this just a discovery followed by a whole pile of guesswork?

  28. ” The thicker Antarctic ice can act like an insulating blanket, preventing the freezing of water trapped underneath the surface.”

    Really? All that ice in Greenland isn’t enough “insulation”? These sorts of ad hoc preconceptions have no place in serious science.

  29. Do they have any evidence that the lakes weren’t there before they just discovered them?

    Cambridge was once a great university (pre-AGW).

  30. Most importantly ……… are there any fish in those lakes ……. and if so …… how can we get there with our tackle?

  31. Leonard Weinstein says:
    November 27, 2013 at 7:24 pm

    To add to what Leonard Weinstein says: I find their explanation of the changes observed in the supra-glacial lake in the vicinity of the sub-glacial lake to be unimaginative. They automatically assumed it had drained because of the ‘complex ice terrain at the supra-glacial lake surface’. In my view the complex ice terrain could equally well have been formed by wind blowing the partially frozen surface to the lee end of the lake.

    Here is an example:

  32. The ice in Greenland is also thinner than that in Antarctica, resulting in colder temperatures at the base of the ice sheet…. The thicker Antarctic ice can act like an insulating blanket, preventing the freezing of water trapped underneath the surface.

    Sounds like the guesses of a high school kid. Can I play? My guess is that it’s the greater pressure of the larger depth of Antarctic ice, not the greater ‘insulation’.

  33. “The setting of the Greenland lakes differs from those of Antarctic subglacial lakes, being beneath relatively thin and cold ice…” Cold ice? is there any other sort?

    Some Antarctic lakes are under ‘thin’ ice as well. Where the ice cover in some Antarctic lakes has been drilled, and water tested, they have been found to have microbial activity. Some have bacterial stromatolites (eg lake Vanda). Most of the microbes live in dark, saline water often with low or zero oxygen and many bacteria provide their energy by sulfate reduction reactions. These are often exothermic (give out heat) and enable the water to maintain temperatures above freezing. There is no need for hot springs. Lake Vostok is a very large lake covered by nearly 4 kilometers of ice. The Russians have recently drilled through this ice and found microbe life.

    Recent research in east Antarctica has found what appear to be huge, active river channels beneath thick ice which appear to connect some lakes with the ocean. I suspect the Greenland subglacial lakes will be similar to those near the south pole!

  34. http://abcnews.go.com/m/story?id=21040063

    http://m.washingtonpost.com/world/japan-south-korea-military-jets-cross-through-china-air-defense-id-zone/2013/11/28/6285d350-5816-11e3-bdbf-097ab2a3dc2b_story.html

    The 21st century superpower, China, sent up planes marking off their new territory. (Not Greenland, yet) My thinkolator imagines Slim Pickens as USAF Major TJ “King” Kong leading a B52, “Now I’ve been to a World’s Fair, a picnic and a rodeo and that’s the stupidest thing I’ve ever heard come over a set of headphones, are you sure you got today’s code?”

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