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Greenland Glaciers Melting Much Faster 460

grqb writes "NASA's Jet Propulsion Laboratory says that satellite observations indicate that Greenland's glaciers have been dumping ice into the Atlantic Ocean at a rate that's doubled over the past five years. Greenland Ice Sheet's annual loss has risen from 21.6 cubic miles in 1996 to 36 cubic miles in 2005 and it now contributes about 0.5 millimeters out of 3 millimeters to global sea level increases. One theory as to why this is happening is that the meltwater, caused by increasing temperatures in Greenland, serves as a lubricant for the moving ice, hastening its push to the sea. Another study has estimated that the warming rate in Greenland was 2.2 times faster than the global norm -- which is in line with U.N. climate models."
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Greenland Glaciers Melting Much Faster

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  • Re:woo (Score:5, Informative)

    by abigor ( 540274 ) on Sunday February 19, 2006 @04:40PM (#14756163)
    Your assertion contradicts the data. Can you give me a reference to back up your claim?

    Here is the real data: http://www.geo.unizh.ch/wgms/mbb/mbb8/sum0203.html [unizh.ch] As you can see, Iceland's glaciers are in a state of retreat.
  • by karmavDogma ( 911769 ) on Sunday February 19, 2006 @04:43PM (#14756176)
    The ESA has data showing Greenland's ice mass getting bigger.
    http://www.universetoday.com/am/publish/greenland_ icesheet_growing.html?4112005 [universetoday.com]
    I don't doubt that human existence is causing some changes in the Earth's environment, but I doubt we've hit the point of no return yet. Besides, if we're ever going to colonize nearby space, we'll needs lots of water. And since this is the only planet we know of to have vast amounts of liquid water (and certainly the only one we readily have access to), perhaps it's not such a bad thing that all the Earth's ice is melting. Adaptation has worked for our species before, I'm sure it can work again.
  • Re:Invade them! (Score:3, Informative)

    by Sandor at the Zoo ( 98013 ) on Sunday February 19, 2006 @04:48PM (#14756217)
    ...allowing science to accurately predict events...

    I'm sorry, where were the accurate predictions? The second paragraph of the actual article says

    The evolution of the ice sheet, in the context of climate warming, is more rapid than has been predicted by models

    From what I can tell, they missed by more than a factor of two. While that's in the same order of magnitude, I don't consider it particularly accurate.

    The article goes on:

    Rignot and Kanagaratnam say their calculations indicate that the Greenland melt currently contributes about two-hundredths of an inch (0.5 millimeters) to the annual 0.12-inch (3-millimeter) rise in global sea levels.

    It looks like it'll be a while before sea levels rise appreciably.

    So, does anyone have some links to actual climate change predictions, especially ones in a chain of predictions that have proven out?

    I've seen a lot of "do you know what a six degree change will do to Kansas?!" But no, I don't know what that would do to Kansas. I've spent most of my life coding software, not studying biology or climate change. So please, someone, give a good couple of links to non-alarmist, non-"the coming catastrophe" kinds of articles. With predictions.

  • by haeger ( 85819 ) on Sunday February 19, 2006 @04:51PM (#14756237)
    I found this interesting link that talks about something called Global dimming [globalissues.org]. I've read some about it and it appears as if the global warming is faster now that a lot of countries have reduced their emissions that blocks sunlight, thus making the greenhouse gases even more "effective".
    It's a scary read. Some evidence seems to support that global dimming might be the cause of famine in Africa.
    There's a lot about the subject on google. [google.com]

    .haeger

  • BBC Article (Score:4, Informative)

    by A beautiful mind ( 821714 ) on Sunday February 19, 2006 @04:53PM (#14756249)
    http://news.bbc.co.uk/2/hi/science/nature/4720536. stm [bbc.co.uk]

    Btw, it is interesting that if you go to the Science/Nature [bbc.co.uk] section on bbc, there are 8 articles dealing with energy crisis/global warming currently, and that number was higher a few days ago when I first checked.
  • by andersa ( 687550 ) on Sunday February 19, 2006 @04:53PM (#14756251)

    No it doesn't. This study only measured iceloss by looking at glacier thickness and velocity around the coast line.

    Inland the ice sheet is actually gaining thickness. There is always a different side to the story. The geophysics department at Copenhagen University, where I have studied (astrophysics though) has thoroughly confirmed this.

    Reference:
    http://www.eurekalert.org/pub_releases/2005-11/esa -eas110405.php [eurekalert.org]

  • by JonBuck ( 112195 ) on Sunday February 19, 2006 @05:00PM (#14756282)
    Here is an article published last year:

    http://www.sciencemag.org/cgi/content/abstract/111 5356v1 [sciencemag.org]

    Recent Ice-Sheet Growth in the Interior of Greenland
    Ola M. Johannessen, Kirill Khvorostovsky, Martin W. Miles, Leonid P. Bobylev

    Abstract:

    A continuous data set of Greenland Ice Sheet altimeter height from ERS-1 and ERS-2 satellites, 1992 to 2003, has been analyzed. An increase of 6.4 ± 0.2 centimeters per year is found in the vast interior areas above 1500 meters, in contrast to previous reports of high-elevation balance. Below 1500 meters, the elevation-change rate is -2.0 ± 0.9 cm/year, in qualitative agreement with reported thinning in the ice-sheet margins. The spatially averaged increase is 5.4 ± 0.2 cm/year, or ~60 cm over 11 years, or ~54 cm when corrected for isostatic uplift. Winter elevation changes are shown to be linked to the North Atlantic Oscillation.
  • Re:woo (Score:2, Informative)

    by b17bmbr ( 608864 ) on Sunday February 19, 2006 @05:13PM (#14756349)
    Cue libertarian anti-environmentalist ranting and argumentative stupidity. Ooh maybe we'll see my favorite, "because there was climate change prior to man, man cannot cause climate change, as any occurrence can have one and only one cause".

    no, it's not stupidity, it's skepticism. the earth changes. the climate changes. thirty years ago, it was global cooling, a new ice age. now it's global warming. we don't know how much, if any, we've contributed to it, and, if we do can do anything about it. we might be able to alter it a few percent over the next fifty years, but at what price. and if we aren't the cause, then we're not the solution. there is lots of room for debate, it's not an absolute certainty. and truthfully, i'm not willing to risk our economic growth and security on a guess. and what about China, Russia, Africa, Latin America, et al. are they going to play by the rules established in "the west"? are they going to sacrifice economic prosperity so a few wealthy nations can once again dictate to the world how to live? hardly.

    the major polluters are exempt from kyoto. and even then, we'll make only modest impact if that. i for one would prefer to see technology and the free markets provide the answers. in some post modern fantasy world, man has become the creator of all things, the omnipotent force, when history has proven completely otherwise. man is subjhect to the whims of the earth, not the other way around. every day the earth is bombarded by the universes biggest nuclear reactor. (that's the sun by the way.) perhaps all the radiation has had an effect? maybe we should build a big canopy and just hide in the shade.
  • Re:Interesting times (Score:2, Informative)

    by wall0159 ( 881759 ) on Sunday February 19, 2006 @05:13PM (#14756351)
    Yup. Without wanting to be alarmist, here's what could happen:

    - massive displacement, disease, starvation caused by rising sea levels
    - increased weather volitility caused by warming oceans, resulting in harsher storms (Gulf of Mexico)
    - Oil wars
    - Widespead famine
    - New diseases, and existing diseases increasing their operational area (eg malaria)
    - Increase in fundamentalism, as people try to understand why these things are happening
    - Fingerpointing ('this is YOUR fault!') and more war
    - destabilisation of trade worldwide
    - destabilisation of democracies worldwide (also - don't think that this wouldn't be exploited. I imagine some of the fundamentalists would try to hasten the downfall of certain democracies)

    It's highly unlikely that climate change will eliminate humanity. However, it could easily destroy our civilisation. Easter islanders went from a reasonably sophisticated fishing society to a group of cannibals living in caves within about 100-200 years. Anyone who doesn't realise how fragile a civilisation is is deluding themselves.
  • by imrdkl ( 302224 ) on Sunday February 19, 2006 @05:18PM (#14756378) Homepage Journal
    That study boldly proclaims a net loss of 2cm/yr below 1500m, and conveniently omits steep inclines, and then to ice the cake (if you'll pardon the pun) declares a positive balance. This latest study sets the melt-rate somewhat higher than the Danes and Norwegians, if I understand correctly, not to mention the effects of erosion - and finds sheets in motion that have been stable, motionless, for literally thousands of years.

    When mean temperature is raised by three degrees, ice melts. It's happeing all over the arctic, and anyone who thought that somehow Greenland would somehow avoid the trend is, literally, all wet.

  • by killjoe ( 766577 ) on Sunday February 19, 2006 @05:33PM (#14756479)
    'I don't know what sort of science fiction you've been reading, but global warming isn't going to make the Earth uninhabitable, or even remotely so. That sort of thing is nothing more than alarmist bullshit."

    I won't make earth uninhabitable bit it will make it more miserable. We can adapt after the population has been culled and after the resource wars have been settled. The balance of power probably won't shift too much, we will probably go ahead and kill lots of people and take over their natural resources and lets face it they can't do jack shit to stop us.

    I don't know if Americans will be happier when it's all said and done but for sure many other countries will be either gone or miserable. I suspect even Americans will have a lower standard of living because most of the foods they are used to eating now will simply be unavailable.
  • by Kymermosst ( 33885 ) on Sunday February 19, 2006 @05:34PM (#14756483) Journal
    Sometimes the old, simple technologies are the answer ...

    Perhaps running a large series of snow making machines drawing water directly from the ocean, or more ideally a fresh water source that deposits into the ocean, 24/7 may be the answer to lower sea levels.

    It wouldn't matter much where in the world this process is done, since water will find its level ... the key is finding an area that's natually very cold to deposit the snow and, ideally, is located near fresh water.


    Thanks for the laugh. The amount of power it would take to do what you suggest (not to mention materials for building the infrastructure) would cause so much fossil fuels to be burned that global warming would increase the entire time you were making snow.

  • Re:NAO (Score:3, Informative)

    by rlk ( 1089 ) on Sunday February 19, 2006 @05:42PM (#14756522)
    Actually, early in the 5-year period the NAO was positive most of the time (in particular, the winter of 2001-2002 had an extreme positive NAO all winter, which led to the eastern US being extremely warm), which most likely corresponded with strong troughing over Greenland. The next three winters were much more dominated by a negative phase of the NAO. For Greenland that would almost certainly translate into net warming over the 5-year period (just like one could argue that it demonstrated strong cooling over the eastern US).

    It certainly does make for interesting speculation about what would happen if the thermohaline circulation were to shut off, as some people predict will happen if ice melt becomes too rapid. One possible outcome would be that the NAO would more or less lock in positive (i. e. a deep trough over the midlatitudes in the Atlantic), which would typically result in strong ridging (much warmer weather) over the eastern US.
  • by man_eleven ( 919353 ) on Sunday February 19, 2006 @05:44PM (#14756527)
    I think he's referring to deforestation, and its tendency to (dramatically) exacerbate drought conditions...

    Mayan deforestation: http://earthobservatory.nasa.gov/Study/Maya/ [nasa.gov]

    Easter Island deforestation: http://earthobservatory.nasa.gov/Newsroom/NewImage s/images.php3?img_id=16861 [nasa.gov]

  • by chromozone ( 847904 ) on Sunday February 19, 2006 @05:57PM (#14756601)
    Areas of rising temperatures trends are real enough but much of the attention given to it is neurotic. We live in societies where moral decay and character deterioration are in morbid, accelerated states. Human nature being what it is, many people not only deny this but they champion such deterioration as "progress". In this dynamic, nagging guilts and anxieties that are suppressed get transferred and fixed to other threats real and/or imagined. People with internal threats fixate on external ones. Acute, cataclysmic global warming is an example. We are more likely on the verge of a deep chill

    With regard to global warming, the "hockey stick" mathematical model used to generate the Kyoto nonsense has been proved wrong. Global warming junk science imposes prejudicial, static, data profiles on dynamic processes. One thousand year periods with notable temperature changes are flattened artificially and recent fluctuations are magnified and held up in isolation (hence the "hockey stick" graph profile).Recent changes in solar activity gets ignored by sensationalists, and data from flawed temperature collections get a pedestal.

    Temperature changes are part of a dynamic process, and the extrapolations based on static "snap shots" of often flawed readings are weird. Many areas in North America and Europe are temperate because of the Gulf Streams warming effect. How many polar ice cubes need to melt before that warm water is reduced and cold temperatures increase?

    Legitimate studies show that rising temperatures are often followed by cooling periods (which can appear in a very sort time). We are all probably better off getting ready for another "little ice age".

    Cataclysmic "gas worries" of the Kyoto type are bizarre. Even the enthusiasts describe only a temperature decline of 0.02C and 0.28C by the year 2050 - and that is no doubt optimistic.

    No doubt we have temperature rises but the emissions bit is psychotic. We have a lot of people who are polluted inside themselves but look outside. Egotistically they think they are at the center of huge, complex global functions. The alarmist junk science that permeates the media is more related to psychological dysfunction than any real global trend. The condemnatory
    "boutique politics" that arise from such junk studies should be isolated to the MTV/Greenday nitwits. That so many "manchurian candidates" in the higher levels of media, science and politics should compulsively conform to the same nonsense is a lot scarier than ice water.

    If this upsets anyone emotionally then know that is how a person becomes in suggestible in the first place. We have real serious threats before us. Tellingly, the people most likely to rant about gasses also minimize the real threats at hand.
  • by blakestah ( 91866 ) <blakestah@gmail.com> on Sunday February 19, 2006 @06:03PM (#14756631) Homepage
    For heavens sake, why is everyone so arrogant to think that our species is capable of uprooting the climate cycle of a planet?

    I know, the idea that there is substantial warming in the northern hemisphere seems strange too....

    Espcially when you look at this photo [solarviews.com]

    I mean, where could all that heat production be coming from?
  • by Wellerite ( 935166 ) on Sunday February 19, 2006 @06:07PM (#14756652)

    Islands like Kiribati and Tuvalu in the Pacific ocean have already been experiencing rising sea-levels [stuff.co.nz] over a period of 13 years according to a tide-gauge project run by Australia's Bureau of Meteorology.

    The rate of about 6mm (0.236 inches) per year is quite slow, but it is significant for low-lying islands like these ones.

  • by Unknown Poltroon ( 31628 ) * <unknown_poltroon1sp@myahoo.com> on Sunday February 19, 2006 @06:32PM (#14756791)
    http://news.bbc.co.uk/1/hi/sci/tech/467007.stm [bbc.co.uk]
    Anyone know anything about this? Its supposed to be the oldest sea levl mark known, and has shown no rise. Is this bullshit?
  • by Wellerite ( 935166 ) on Sunday February 19, 2006 @06:46PM (#14756863)
    Don't know about that one, but Australia's Department of Environment and Heritage has data, [deh.gov.au] going back to around 1900 showing 12 to 16 cm increases in sea-levels in the 20th century.
  • by LocalH ( 28506 ) on Sunday February 19, 2006 @06:53PM (#14756901) Homepage
    They're saying that the rate itself doubled, not the total loss.
  • Re:Invade them! (Score:3, Informative)

    by HiThere ( 15173 ) * <charleshixsn@ear ... .net minus punct> on Sunday February 19, 2006 @07:11PM (#14756981)
    Well, actually it was predicted by several people...and denied by others. The government sided with the deniers, so that was the "official theory". (Also, since it was still being disputed, most scientists sat on the sidelines without evidence of their own, and tried to evaluate what was offered.)

    This event was predicted sufficiently long ago for "The Day after Tomorrow!" to be on the screens last year. (It might have been lousy science, but it was based on good science.) Go to see it...then imagine the events stretched over a century or two instead of less than a year. That will be a gloomy reading of "What happens if Greenland melts too quickly?". Plausible, but not certain. (Also, forget about those super ice storms...though SOMETHING froze mammoths quickly enough that their stomachs still contained undigested soft green plants. Artistic exaggeration strikes again.)

    The problem is that the oceans are too warm. That means that a whole lot of water surface is evaporating at a quick rate. If it comes down as rain, you get super hurricanes and monsoons, etc. If it comes down where it's cold, you get ice and snow. If the "great conveyor" shuts down between Florida and Iceland, then eastern North American and western Europe will get a LOT colder. Cold enough to allow snow to again build up. The last time this happened glaciers scooped out the great lakes (and Yosemite Valley). We don't know how quickly the change happens, but it could be very quickly. It can't happen too slowly, or the oceans would cool down before evaporating enough water to create massive glaciers. ... Of course, once the glaciers form, the entire planet starts cooling down (unless the CO2 level provides enough greenhouse effect to stop this...dubious). Etc.

    Caution: I Am Not A Climate Scientist. I've only read a few popularizations that explored the thermodynamics of the process. But they made it clear that large glaciations tend to form QUICKLY (but this is based on the geological record, so just what QUICKLY means isn't clear).

  • by arkhan_jg ( 618674 ) on Sunday February 19, 2006 @08:32PM (#14757538)
    If the atlantic conveyer slows or stops, then northern and western europe will get colder. All sorts of changes will happen.

    The global temperature will still go up overall though. Changes will include an increase in temperature near the equator, and reduced rainfall in the existing temperature zones, causing big effects for farming. Storms will get more powerful, and sea levels will rise.

    As with any big complex system, you introduce more energy (temp=energy), the system gets more chaotic. We can't say with certainty what will happen, or when exactly it'll happen, but it won't be fun or cheap to deal with. You won't see a decades cycle for glaciers though, as the system doesn't change that fast. We're starting to see the effects of 100 years of huge amounts of CO2 being pumped into the atmosphere. The effects will carry on getting worse for decades, even if we drastically cut emissions now. If we don't, we just make things even worse for our children and grandchildren. I think they're really gonna hate us for not doing anything about our ongoing mess, even though we knew what we're causing.
  • Re:NAO (Score:3, Informative)

    by shellbeach ( 610559 ) on Sunday February 19, 2006 @08:48PM (#14757633)
    Ummm... if we're headed for another ice age then how do sea levels rise? Isn't all that excess water tied up in, well, snow and ice? As in ice age? ;)

    I think he's talking about the potential of much colder winters in Europe (and only Europe) thanks to the gulf stream slowing down/completely stopping (see, for example this paper [nih.gov] for recent evidence of changes to the gulf stream flow)
  • by dsfox ( 2694 ) on Sunday February 19, 2006 @08:54PM (#14757676) Homepage
    To use similar, but more reasonable logic to the previous poster, if it continues to double every five years, that means the entire 6096 mm will be gone in x years where

        2 ^ (x / 5)= 6096
        (x / 5) log 2 = log 6096
        x = 5 log 6096 / log 2

    or 63 years.
  • Re:NAO (Score:1, Informative)

    by Profane MuthaFucka ( 574406 ) <busheatskok@gmail.com> on Sunday February 19, 2006 @10:17PM (#14758167) Homepage Journal
    If you want to increase the correctness factor of your post, which is already pretty correct, you should mention that the evidence that the current warming is caused by humans is increasing. That is just a statement about what the studies are concluding, not a judgement about the correctness of the conclusions.
  • Correct (Score:3, Informative)

    by gregm ( 61553 ) on Sunday February 19, 2006 @11:04PM (#14758378)
    You're correct... floating ice does not make the water level rise. However, melting ice that was supported by a land mass that is not floating in the water will indeed make the water level rise.
  • Alarmist (Score:3, Informative)

    by umbrellasd ( 876984 ) on Monday February 20, 2006 @01:38AM (#14758984)
    The poster a few posts up did not say Earth would be uninhabitable. He just said our current lifestyle would become unsustainable. For certain, if the planet does warm significantly, you will have elevated sea levels that flood many major metropolitan areas all over the world, and that will cause some havoc in real estate and the market in general. Then there is the effect of climate change on food production. I guess one bonus is that the need for heating oil goes down, :-). This is assuming the heating scenario does not trigger a mini-glacial period.

    The way I see it, the most likely fallout of planet wide warming is an increase in infectious diseases. Take a look at the avian bird flu as it is slowly spreading across the world despite our best efforts to contain it. The higher the temperatures go, the more interesting the disease become. It's no accident that the most virulent diseases in the world are in warm moist climates.

    Even that is not an alarmist thing to say. We can adapt. But in a warmer Earth, I think disease may play a bigger roll in population reduction than many anticipate. In a colder Earth, we play the bigger role by killing each other for diminishing food and fuel resources. Pick your poison.

    I know there are always a lot of people that say, "Hey, it is not so bad. We will adapt. Etc." But I think everyone can agree that the tone of commentary on the planets climate has shifted pretty dramatically since I was in school 15 years ago. We've got some serious trends emerging including high hurricane activity (with unusual electrical properties never before witnessed), rapid melting of glaciers that is outstripping the predicted rates by our best scientists (just today recent data is showing Greenland melting far faster than we predicted even 5 years ago and the arctic shelves are calving into the ocean at a rapid rate), increased threat of a pandemic despite our rapidly increasing scientific knowledge in the field of epidemiology (right now we are looking at a bird flu which is a hit on our food rather than on our population directly), and of course, our dwindling fossil fuel supplies upon which our industries are based.

    That last one I put in there as an indicated of economic stresses on the system. We will feel some pressure from that one. Yes, we can transition away from fossil fuels, but if you combine the economic pressure from that with rising sea levels displacing industry and people, greater likelihood of worldwide epidemics (sure the US is pretty covered but 3rd world countries should be terrified by this possibility more than a US citizen could likely imagine), and so on.

    Any one of these things, we can deal with, but we are not confronting just one thing. We are confronting a multitude of things that are all converging on our current way of life: an unsustainable one. Heck, I work in health care and I know the exponential cost projects very well. We can't sustain the costs. There's just no way. Something will give within the next 10 to 20 years...which again coincides with all these other things. There's a big pattern here. I don't think many people see the forest for the trees on this right now. You can argue about this one posts topic, but it's just one topic of a dozen that are all pointing toward, "Ouchtime".

    I don't think it's hopeless, but I think there's a Hell of a lot of work to do in the next 20 years. People need to start making right choices on their own and helping their neighbors to get educated and shift their life choices toward a path that protects us from the problems on the horizons. In health care, it's simple things like HSAs that let you get tax free payroll deductions into an investment account to pay for health care and getting more educated about what treatment you really need and what you don't (you might not need that drug the Doctor is being paid to prescribe--sometimes you do). Here's a fact: health care costs are rising exponentially and well beyond the capacity of our insu

  • by ankhank ( 756164 ) * on Monday February 20, 2006 @02:07AM (#14759114) Journal
    The last line you quoted is the key -- increased snowfall is cyclical, linked to the North Atlantic Oscillation.

    The accelerated flow of the ice into the ocean, by contrast, is new and apparently related to warmer ocean and maybe meltwater from the surface of the ice flowing down through crevices and lubricating it.

    The natural forces are cyclical (aside from the fact that the sun will continue to become warmer until it becomes a red dwarf and swallows the planet, but that's later).

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