Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Science

Greenland's Fastest Glacier Sets New Speed Record 136

vinces99 writes "The latest observations of Jakobshavn Glacier show that Greenland's largest glacier is moving ice from land into the ocean at a speed that appears to be the fastest ever recorded. Researchers from the University of Washington and the German Space Agency measured the speed of the glacier in 2012 and 2013. The results were published Feb. 3 in The Cryosphere, an open access journal of the European Geosciences Union. Jakobshavn Glacier, which is widely believed to be the glacier that produced the large iceberg that sank the Titanic in 1912, drains the Greenland ice sheet into a deep-ocean fjord on the west coast of the island. This speedup of Jakobshavn means that the glacier is adding more and more ice to the ocean, contributing to sea-level rise. 'We are now seeing summer speeds more than four times what they were in the 1990s, on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland,' said lead author Ian Joughin, a glaciologist at the UW's Polar Science Center. The new observations show that in summer of 2012 the glacier reached a record speed of more than 10 miles (17 km) per year, or more than 150 feet (46 m) per day. These appear to be the fastest flow rates recorded for any glacier or ice stream in Greenland or Antarctica, researchers said."
This discussion has been archived. No new comments can be posted.

Greenland's Fastest Glacier Sets New Speed Record

Comments Filter:
  • by Spy Handler ( 822350 ) on Tuesday February 04, 2014 @11:10PM (#46158849) Homepage Journal

    the glacier will break Mach 1 by 2016 when Hillary is president and Al Gore is secretary of state.

  • Greenland has experienced (like Antarctica) some very heavy snowfalls in the past few years, which increases the thickness of the glaciers. Glacial flow is fairly well understood, as the glacier gets thicker it causes faster movement.

    The calving of large glaciers is often touted by alarmists as proof of their claims, but this phenomenon does not actually support the alarmist position at all.

    • You were doing good until you used the word "alarmist", at which point, poof! Bye, bye, credibility.
      • And those who use the word "Denier" are more credible?

        • by erikkemperman ( 252014 ) on Wednesday February 05, 2014 @01:26AM (#46159613)

          I don't think neither "alarmist" nor "denier" are very helpful. Let's ask the climate scientists, in stead. Once again [wikipedia.org]:

          In the scientific literature, there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused primarily by human-induced emissions of greenhouse gases.[2][3][4] No scientific body of national or international standing disagrees with this view,[5] though a few organizations hold non-committal positions.[6] Disputes over the key scientific facts of global warming are now more prevalent in the popular media than in the scientific literature, where such issues are treated as resolved, and more in the United States than globally[7][8].

          • In the scientific literature, there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused primarily by human-induced emissions of greenhouse gases.[2][3][4] No scientific body of national or international standing disagrees with this view,[5]

            And on the other side we have a massive political campaign to deny climate change:

            https://www.google.com/search?... [google.com]

            http://www.scientificamerican.... [scientificamerican.com]

            • So about $558 million over that period (2003 to 2010)

              Its still nothing compared to US Federal spending on climate change for that same period (over 106 billion dollars).
              http://www.forbes.com/sites/la... [forbes.com]

              So whats so bad about spending 0.5% of federal climate change spending to try and get the message out that not everyone is in agreement with it?

              Seriously, 558$ million, what a big number. Lets scare the sheeple that read the news.

              Honnestly, $106 billion spent over an 8 year period, is insane IMO.

              $106,000,000,

        • Re: (Score:2, Insightful)

          by Joce640k ( 829181 )

          And those who use the word "Denier" are more credible?

          Well.... I never saw a "Denier" who could post credible data (usually they don't post any at all).

        • Comment removed based on user account deletion
        • by dbIII ( 701233 )
          I prefer "luddite", "merchant in the temple" or "christianity-lite". Those pricks that went after geology, biology and now climate science are doing it just to try to make it look like they know more than anyone that went to school.
    • by hey! ( 33014 )

      Seriously, you think pressure for *annual snowfall* makes a dramatic difference in the speed of the Jakobshavn glacier. this [northlandscapes.com] Jakobshavn glacier. The one that's two kilometers thick [wikipedia.org].

      • Yes, snowfall does make a difference. It compresses to ice, and Greenland's ice sheet has been thickening since the early 1990s [esa.int]. Now 6 cm/yr may not sound like a lot of additional thickness, but since 1993 that's at least 1.2 meters additional thickness (records prior to 1993 aren't that accurate - the satellites don't exist). It may be even more than that over the preceding decades as well. Given that ice weighs around 920 kg/m^3, and there are ~1.7 million km of Greenland ice sheet, the gains since 19
        • "Now 6 cm/yr may not sound like a lot of additional thickness, but since 1993 that's at least 1.2 meters additional thickness"

          6cm a year sounds like a hell of a lot to me. If your backyard gained 6cm more of new ice every year, you would not think it was trivial. And if you had to haul it all away, a piece at a time, you'd damned well know that much weight isn't trivial.

        • by hey! ( 33014 ) on Wednesday February 05, 2014 @02:12AM (#46159817) Homepage Journal

          What you're talking about is 1.2 meters of new ice on top of *two kilometers* of primordial ice. If we scaled the ice sheet to 2 meters tall, the extra accumulation would be roughly the thickness of a piece of paper.

          In any case, you're confusing the vast, 400,000 year-old interior ice sheet with a coastal glacier. It makes no difference that the interior ice sheet has thickened very slightly because measurements of the *glacier in question* show that *it* is thinning.

          • And what you do is talk about 1950's to 2012, 1900 to 2012, 1800's, 1600s, 1AD, 2000BC....

            All of these dates a mere slivers in climate history. And most anything beyond those dates is circumspect. Based on assumptions with little proof.

            Sure you can measure CO2 levels in ice cores from thousands or hundreds of thousands of years ago. And declare they were significantly lower in the past. But you have zero knowledge of how much CO2 is lost over thousands and millions of years.

            Gasses like to escape. Even h

        • The center of Greenland's ice sheet may be thickening but over all Greenland is losing ice mass at a rate of over 260 Gt per year since 2002 as measured by the GRACE satellites. See the Total Ice Mass section of this report [noaa.gov] for details.

        • by geekoid ( 135745 )

          NO it hasn't. Geez, 1 article form 2005, and it doesn't measure mass; which has been declining.
          I will admit, that was one of the better attempts at cherry picking.
          It's been loosing more mass then gaining:
          http://www.ipcc.ch/pdf/assessm... [www.ipcc.ch]

          really, what is your problem? The science is sound. I wonder, do you know the science? i mean, you seem to cherry pick the predictions of the science, but do you know even the basics of the science?

    • by jovius ( 974690 ) on Wednesday February 05, 2014 @01:24AM (#46159605)

      Snowfall needs moist air. Warmer air holds more moisture. Increased snowfall is well in the scope of what's been thought to happen. There really doesn't need to be any alarmist campaign; simple scientific observation of the amplified greenhouse effect is enough.

      • "simple scientific observation of the amplified greenhouse effect is enough"

        Of course, that amplified greenhouse effect appears to be missing everywhere that we can actually measure.

        • by geekoid ( 135745 )

          No it isn't. why the hell would you say that? This article talks about it

          the amplified green house effect is EVERYWHERE we look.

        • by cusco ( 717999 )

          You need to travel more. Glacier National Park has a series of slides showing the retreat of all their glaciers. Coastal glaciers in Alaska are retreating so fast that Princess Cruises has had to change their glacier viewing routes. A photo of Huaraz, Peru from 1947 shows mountain peaks on both sides of the valley covered in glaciers, when I first went in 1986 only the eastern range had glaciers, when I went a few years ago half of the eastern range is now bare. There are valleys in Chile and Argentina

    • by riverat1 ( 1048260 ) on Wednesday February 05, 2014 @01:33AM (#46159649)

      I did a little searching and found a paper from 2011 [pdf] [science.uu.nl] that addresses Jakobshavn specifically. It has this to say:

      3.3. Jakobshavn Isbroe

      Jakobshavn Isbroe was losing 8 Gt a1 of mass per year in 2000 (Figure 2). This rate increased over the following years to near 25 Gt a1 by the end of 2002. The loss rate then stabilized and declined back under 20 Gt a1 until 2006, when it increased to 33 Gt a1, reaching 34 Gt a1 by the end of 2007. Subsequently, the annual loss rate has fluctuated between 25 and 33 Gt a1. In total the glacier lost 321 ± 12 Gt by the end of 2010, equivalent to a basin!wide thinning of 3.5 m, with 2/3 of this loss occurring since June of 2005 (Figure 3). The 85 km2 of retreat accounts for nearly 20% of this loss. The rate of discharge is now such that the glacier is losing mass nearly throughout the year. As previously reported [Joughin et al., 2008a, 2008c; Luckman and Murray, 2005], annual oscillations in speed of ±20%, with a peak in June/July, correlated with seasonal retreat and advance of the ice front, become increasingly pronounced at the location of the fluxgate after 2005 (Figure S7). Seasonal oscillations in speed, SMB and front position cause annual fluctuations in mass of up to 50 Gt.

      Of the other two glaciers reported on in the paper Helheim gained 17 +/- 13 Gt and Kangerdlugssuaq lost 152 +/- 10 Gt compared to Jakobshavn's 321 +/- 12 Gt in the 11 year period studied. Those are the three largest outlet glaciers in Greenland.

      More generally the ice mass loss on Greenland [noaa.gov] has been well documented by the GRACE satellites. See the Total Ice Mass section of the Arctic Report Card: Update for 2013 [noaa.gov] for details.

      • Errata: The "a1" in the quote showed as "a-1" in the original and stands for per annum or per year.

    • Re: (Score:3, Insightful)

      Greenland has experienced (like Antarctica) some very heavy snowfalls in the past few years, which increases the thickness of the glaciers. Glacial flow is fairly well understood, as the glacier gets thicker it causes faster movement.

      An observant person might note that the fact that is now snowing in places where it was previously too cold to snow is actually an indication of change, not an argument against it.

      The calving of large glaciers is often touted by [scientists] as proof of their claims, but this phenomenon does not actually support the [scientists] position at all.

      You are mistaken. Climatologists don't claim that glacial calving is proof of AGW - this proof lies in the observations and theories of Tyndall, Fourier, Arrhenius et al.

      I'm not sure what it is about Climatology that makes people think that ignorance can substitute for knowledge. Does this muddled thinking work, say, when you

      • "this proof lies in the observations and theories of Tyndall, Fourier, Arrhenius et al. "

        The experiments Fourier wrote about (actually performed by de Saussure), were examples of the "real" greenhouse effect; that is, they involved what amounted to a real greenhouse (an enclosed space which did not allow heat to escape via convection). But Fourier's speculations were about a DIFFERENT effect, in which layers of air trapped radiation.

        We now know that the "greenhouse effect" popularized by greenhouse gas warming theories does NOT work by the same principle as a real greenhouse, or the experime

        • by riverat1 ( 1048260 ) on Wednesday February 05, 2014 @04:16AM (#46160319)

          Fourier's discovery that the Earth was warmer than it should be given its size and distance from the Sun was a major step forward in geoscience.. That he may not have had the mechanism right in no way detracts from the importance of that insight.

          • Ah yes, the right answer using the wrong method. Is there anything more delusional than that?

            • by dbIII ( 701233 )

              Ah yes, the right answer using the wrong method. Is there anything more delusional than that?

              In that case take that up with Newton and gravity too.

              WTF is it with these luddites?

              • What abut Newton's method was wrong, pray tell?

                P.S. The general term "Luddites" refers to people who are opposed to technological progress. It does not refer to those who think someone else's science is flawed.

                So for example: someone who wanted to shut down a power plant might be called a Luddite. Someone who wanted to keep it running would not be.
                • by dbIII ( 701233 )
                  The word is in there - "gravity" - Newton didn't quite get it right. It's a good example as to why expecting instant perfection is an unreasonable attitude in science (or anything really).

                  The general term "Luddites" refers to people who are opposed to technological progress

                  Yes.

                  It does not refer to those who think someone else's science is flawed.

                  People who think an entire field of science is invalid and then make a statement that suggests that the entire scientific method is flawed are a different case. S

            • He had the right answer, but most of his proofs had been disproven by contemporary scientistis. He was too egotistical to accept their theories (which history later proved correct), and thus was an unabashed ass in many ways. Who felt that he was beyond the need for the peer review / publication process of his day.

          • "Fourier's discovery that the Earth was warmer than it should be given its size and distance from the Sun was a major step forward in geoscience."

            It wasn't a "discovery", it was a calculation, AND it was a calculation based on false assumptions, because he simply did not have the information about it that we have now.

            To put it bluntly: even if he did arrive at the right solution via his calculations (which is very questionable), he was still wrong. For example: the sunward surface of the moon, even when it is fullest (i.e., the furthest parts of its wobbly orbits about the sun) is FAR hotter than the surface of the earth... and the ONLY significan

        • Hopefully you didn't suppose that I meant that the greenhouse gas theory was somehow fully formed in the 1820s - because if so your supposition was wrong.

          He proposed the theoretical foundation, Tyndall demonstrated the mechanism by his work with radiative absorption - Arrhenius quantified it.

          If the aim of the conspiracy theorists is to disprove AGW they need to disprove the work of these giants.

          • He (Fourier) proposed the theoretical foundation, Tyndall demonstrated the mechanism by his work with radiative absorption - Arrhenius quantified it.

            Nicely and succinctly put. I'm going to steal that.

            • "He (Fourier) proposed the theoretical foundation"

              Fourier proposed an IDEA, based on flawed assumptions and resulting flawed calculations. I am not "blaming" Fourier... such was the state of science at the time. But modern science would not arrive at his conclusions, given the same raw data. He gets credit (if that is the right word) for conceiving of the idea, but his theoretical work and calculations are useless due to too many flawed assumptions.

              Tyndall showed that gases can warm by absorbing radiation, and cool by emitting it. I have no criticism of

              • Fourier proposed an IDEA, based on flawed assumptions and resulting flawed calculations. I am not "blaming" Fourier... such was the state of science at the time. But modern science would not arrive at his conclusions, given the same raw data.

                Summary Fourier was right.

                Tyndall showed that gases can warm by absorbing radiation, and cool by emitting it. I have no criticism of Tyndall's work.

                Summary Tyndall was right. There is no known refutation of Tyndall that would cause us to doubt that CO2 and other greenhouse gases are a driver for climate change.

                Arrhenius attempted to quantify it. He came up with some potentially useful calculations but they were based on indirect observation and yet more assumptions. (I.e., he assumed CO2 and water were what were retaining heat in the atmosphere).

                Summary Arrhenius was right.

                Kurt Angstrom rebutted Arrhenius' work. Angstrom's rebuttal was basically shouted down; I know of no actual refutation of Angstrom's criticisms.

                Summary You heard that someone said something criticising some part of Arrhenius' work. This person was then "shouted down" which I assume means "proven wrong" pending further evidence. Summary of Summary You can't detail any evidence refuting Arrhenius' early work on quantifying the sensitivity of climate to CO2 and othe greenhouse gases, and probably you yourself don't believe there is a problem with it, but can't say so publicly.

                • "Summary Fourier was right."

                  No, he wasn't. The "greenhouse gas trapping radiation" explanation he imagined for the effects observed in the de Saussure experiments existed in his mind only and still does not exist. The heating in de Saussure's hotbox experiments was solely due to solar heating, and prevention of convective cooling. See the reconstruction here. [postimg.org]

                  In other words, exactly like a real greenhouse, which works the way I just described, NOT via trapping of radiation.

                  Fourier's explanation was that the trapped gas also "trap

                • "Summary Tyndall was right. There is no known refutation of Tyndall that would cause us to doubt that CO2 and other greenhouse gases are a driver for climate change."

                  Actually, I just learned that this too is not true. Not only did Tyndall get absoptivity and opacity confused, he also based his work on the assumption of the "luminiferous aether", which we of course know today does not exist. It is simply not valid to take a work that is based on the concept of "aether" and say it is vindication of ANY modern scientific theory.

                  Nowhere does Tyndall mention measuring the component of radiation reflected by the gases he examines... This is in spite of Tyndall's having handled chlorine gas, which is coloured by its reflection of visible light. It is clear that Tyndall measured opacity and relative opacity, not absorptivity and absorption as he seems to claim. In fact, Tyndall uses the terms "opacity" and "absorbing power" interchangably throughout his work. This is indicative of a fundamental misunderstanding, which is nonetheless studiously avoided by nearly all authors who claim that Tyndall's work proved the "Greenhouse Effect". In fact, it was another fundamental misunderstanding that lead to the proposition of the "Greenhouse Effect".

                  (Quote Tyndall) "I have already adduced considerations which show that the molecules of rock-salt glide with facility through the ether; but the ease of motion which these molecules enjoy must facilitate their mutual collision. Their motion, instead of being expended on the ether which exists between them, and communicated by it to the external ether, is in great part transferred directly from particle to particle, or in other words, is freely conducted. When a molecule of alum, on the contrary, approaches a neighbour molecule, it produces a swell on the intervening ether of space, which swell is in part transmitted, not to the molecules, but to the general ether of space, and thus lost as regards conduction. This lateral waste prevents the motion from penetrating the alum to any great extent, and the substance is what we all a bad conductor."

                • "This person was then "shouted down" which I assume means "proven wrong" pending further evidence."

                  "This person" is no less than Kurt Angstrom, and no, "shouting down" means loudly proclaiming "NO! You're wrong!" without any supporting evidence.

        • It sure is a shame the no one has done any science since Fourier. Imagine the things we could have learned if only there were someone who could take his work and continue to study the greenhouse effect.

          • "It sure is a shame the no one has done any science since Fourier. Imagine the things we could have learned if only there were someone who could take his work and continue to study the greenhouse effect."

            It sure would be interesting. Let me know when that happens. Quote Wikipedia:

            "Arrhenius estimated that halving of CO2 would decrease temperatures by 4â"5 ÂC (Celsius) and a doubling of CO2 would cause a temperature rise of 5â"6 ÂC.[10] In his 1906 publication, Arrhenius adjusted the value downwards to 1.6 ÂC (including water vapor feedback: 2.1 ÂC). Recent (2007) estimates from IPCC say this value (the Climate sensitivity) is likely to be between 2 and 4.5 ÂC."

            So let's see... Arrhenius estimated climate sensitivity to be 2.1 degrees C. Modern "science" says it's somewhere between 2 and 4.5 degrees C.

            Doesn't look like much progress to me over the last 100 years. We've maybe learned to place error bars around out calculations. That's about it.

      • > An observant person might note that the fact that is now snowing in places where it was previously too cold to snow is actually an indication of change, not an argument against it.

        "Too cold to snow?" Really, now?

    • In the case of basal sliding, the entire glacier slides over its bed. This type of motion is enhanced if the bed is soft sediment, if the glacier bed is thawed and if meltwater is prevalent.

      It's the FASTER melting that causing the increase of speed.
      You do understand this is about increased melting, right?

  • by Anonymous Coward

    Does this mean that in a few years they will have to re-define the term "at glacial pace"? :)

  • Good news! (Score:1, Redundant)

    by tsprig ( 167046 )

    If anyone thinks you're working at a glacial speed, you are now 4x as fast as you were in the 1990's. Now THAT is progress!

  • Kill all humans (Score:2, Interesting)

    by musmax ( 1029830 )
    You know I don't really care about the number of humans the impeding environmental crisis will kill off, the more the better, as long as its not me of course, and it will take at least 50 years, by which time I will be dragged to my grave by my fat ass. In all probability it will be some brown nobody that cooks his food over a dung fire in Asstonia, and who gives a fuck about that ? What concerns me more is the sterile wasteland the survivors will create. I mean its nice to "conserve" some splatter of gree
  • I'm still a bit confused on those speeds. Can someone convert them to coincide with the viscosity of tar pitch [slashdot.org] or the rate by which bills get passed through congress?

    • Bit faster than the first, way faster than the second, for typical values of bit and way.

    • by rossdee ( 243626 )

      Viscosity is an inverse measure of speed

      Bills passing congress is measured in Repeals of ObamaCare per session

    • The Designed In Idiocy of the Slashdot Poster

      For over a decade the Slashdot poster has brought ignorance, libel, and the most inestimable repetitive motion, face-palming injuries to have afflicted the general public. With Medea-like intensity, this mass trauma began rising sharply four years ago, reflecting new and unexpected ravages by the keyboards of tens of thousands of monkeys and/or basement dwellers. A 2009 Department of Commerce report projected that 51,000 persons would be rendered eternally speechless by Slashdot posting atrocities in 2025. That figure will probably be reached in 2015, a decade ahead of schedule.

      • "For over a decade the Slashdot poster has brought ignorance, libel, and the most inestimable repetitive motion, face-palming injuries to have afflicted the general public."

        Must ... resist ... temptation... to... snark...

        Ah. There. I did it. Hooray for me.

      • by dbIII ( 701233 )
        Why are you here then? Do you get paid for your science denial or do you just like trolling people?
  • The glacier is moving a record speeds. This is due to massive accumulation of ice putting pressure on the glacier. Ice....wait.....

    I thought ice was only growing in the Antarctic region, NOT the Arctic. But now you tell me it is increasing there too.

    (And darn, if it ain't increasing on my home as well.)

    • by cusco ( 717999 )

      Fail. Coastal glacier, no connection to the inland ice mass. Inland is also losing mass as well. This is pointed out in any number of posts above, which you managed to ignore in your rush to post this bit of foolishness.

Is knowledge knowable? If not, how do we know that?

Working...