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

 



Forgot your password?
typodupeerror
×
NASA Earth

NASA Satellite Measurements Show Unprecedented Greenland Ice Sheet Melt 411

NASA reports that measurements taken from orbiting satellites indicate the Greenland ice sheet underwent melting over a larger area than they've seen in 30 years of observations. On July 8, the satellites found evidence that about 40% of the ice sheet's surface had melted. Observations just four days later showed 97% of the surface had melted. "This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland's weather since the end of May. 'Each successive ridge has been stronger than the previous one,' said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate. Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H. A National Oceanic and Atmospheric Administration weather station at Summit confirmed air temperatures hovered above or within a degree of freezing for several hours July 11-12." Photos also surfaced last week showing the Petermann Glacier in Greenland 'calving' — some very large chunks of it broke off and started to drift away.
This discussion has been archived. No new comments can be posted.

NASA Satellite Measurements Show Unprecedented Greenland Ice Sheet Melt

Comments Filter:
  • by oraclese ( 1039520 ) on Tuesday July 24, 2012 @08:33PM (#40759025)
    At the risk of sounding like a denier, I'm not going to freak out just yet, since it says in the article (and partially in the summary) that this is believed to happen every 150 years or so, last time being 1889.
    • by PortHaven ( 242123 ) on Tuesday July 24, 2012 @08:43PM (#40759147) Homepage

      No, no....you DON'T UNDERSTAND!!!!

      2012 - 1889 is only 123 years. This is nearly 30 years too soon. This is dire!!!!

    • by HTH NE1 ( 675604 )

      this is believed to happen every 150 years or so

      "I love humans. Always seeing patterns in things that aren't there." -- The Doctor

      • by TapeCutter ( 624760 ) on Tuesday July 24, 2012 @09:42PM (#40759651) Journal
        That's why we invented maths. Statistically a heatwave like the one in TFA occurs on AVERAGE once in 150yrs, technically if we get a couple more like it in the next decade or so it could still be due to "luck", the same technicality applies even if the entire ice cap melts, it could still be just a random once in a 100M yr event. - The same unreasoning was used by the same immoral stink tanks to convince people that smoking did not cause cancer. A single extreme weather event is obviously not enough to determine a weather pattern, but that is not what they are claiming.
        • it could still be just a random once in a 100M yr event

          The Earth's climate is known not to be stable on that sort of timescale, and in fact even on far shorter timescales (e.g. Ice Ages). Hence there is no practical way of knowing whether such an event is a one-off fluke or an indication of a change in the climate. The possibility is to hope the climate remains stable for the next 1,000+ years and then to see whether it occurs again...but the wait will be a long one! It's probably safe to say that once in a 100 MYr events are unlikely to occur twice in a mille

        • by Jawnn ( 445279 )
          Quite correct. One hot summer, one stormy winter, even several in a row, does not a climate change make. But a widespread pattern of those, globally, is a very strong indicator that the planet is heating up. Those indicators are the predictable results of more energy in the atmosphere. So..., by itself, this summer's melting of the Greenland ice sheet is not "proof" of anything. Taken along with the many similar statistical "unusual" weather patterns around the planet? Maybe not so much.
      • Any chance we can borrow his Tardis and go back and see what rhe Greenland ice sheet was like 500 years ago, 1000, 10000 etc.

    • I saw that, and thought, "have we drilled enough ice cores in enough places to know that the previous melts covered 97% of the ice cap?"

    • Unprecedented (Score:3, Interesting)

      by Dan East ( 318230 )

      It's always interesting when an article provides precedence for something it labels unprecedented.

  • Interesting Caveat (Score:5, Insightful)

    by Grizzley9 ( 1407005 ) on Tuesday July 24, 2012 @08:38PM (#40759087)

    Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H

    It's scary if you look at a trend of only 30 years. And then you compare it to data that's only around 120 years old and find out it's not so bad. I'm not saying the melting isn't bad, just seems to be presumptions to say "unprecedented" and alarmist to use such language given the number of data points.

  • Atlantic Currents (Score:5, Informative)

    by gznork26 ( 1195943 ) <gznork26@@@gmail...com> on Tuesday July 24, 2012 @08:39PM (#40759105) Homepage

    With that much fresh water being added to the North Atlantic, we ought to be talking about the health of the Atlantic Ocean currents that are energized by the temperature difference between equator and polar regions, and the deep water exchange, which is driven by the difference in salinization. Most important of these currents is the Gulf Stream. It stopped several hundred years ago, over the course of a single lifetime, and caused the Little Ice Age in Europe. I've already heard some reports about the speed of the current slowing. An awful lot depends on those currents, and we've heard nary a peep about the implications.

    • Re:Atlantic Currents (Score:5, Informative)

      by phantomfive ( 622387 ) on Tuesday July 24, 2012 @09:08PM (#40759371) Journal

      and we've heard nary a peep about the implications.

      I don't know why you haven't heard a peep, scientists have taken this quite seriously and have done some research on the topic. The difficulty, of course, is good historical data is hard to find, and frankly, good measurements of the entire ocean are not easy to make even now.

      In any case, the latest scientific research [nature.com] suggests little cause for alarm.

    • Erm, you know how tiny that volume of water is, comparatively?

      If that kills something off, that thing was going to die the next time a fish shat in the water next to it anyway.

    • So how is it bad if Europe gets another Ice Age?

    • Re:Atlantic Currents (Score:4, Interesting)

      by techno-vampire ( 666512 ) on Wednesday July 25, 2012 @01:18AM (#40760841) Homepage
      ...and caused the Little Ice Age in Europe.

      Not just in Europe. In 1776, Alexander Hamilton was able to drag the guns of Fort Ticonderoga across the frozen Hudson River to New York. By 1830, the ice on the Hudson was too thin for that, and by 1850 or so, it had completely stopped freezing over.
    • Re:Atlantic Currents (Score:5, Interesting)

      by Xest ( 935314 ) on Wednesday July 25, 2012 @05:20AM (#40762031)

      Well in the UK I think we're probably prepared. This last 7 years or so we've seen everything from massive increases in rain through to winters that have been about 20C below historical averages.

      In each case it's been because the jetstream has moved out of it's normal position. In March we had drought conditions across most of the country, since then we've had record historical rainfall ever recorded for the month of July and so forth. In 2010 we had a January/February that was so bad we hadn't seen one like it for about 40 years, by November that year it happened again, so from once in 40 years, to twice in a year. Last winter was unusually mild, we barely even went below 0C which was in stark contrast to the -20C we'd seen the two winters previous. For reference, normal winters would see lows of -6C to -8C where I live.

      Perhaps it's a natural cycle, perhaps it's because of man's actions, but either way the jetstream running over the UK has been acting quite differently to what we're used to since at least 2005. It could well be that effects on the gulfstream are already causing what you suggest.

      On the upside, whilst the weather we've had with a lack of jetstream in it's normal position is not pleasant, it's certainly not going to be the end of civilisation at least - we've managed to cope the last few years, but it seems it means we don't get proper summers anymore.

  • You said it first (Score:4, Insightful)

    by shutdown -p now ( 807394 ) on Tuesday July 24, 2012 @08:40PM (#40759115) Journal

    I love how neither the article, nor the summary mention global warming - heck, it's not even in the tags! - but in the first ten posts, half are already decrying the "AGW alarmists".

    • Well, I can post an whole article and summary on the decline of auto manufacturing leading by to the decline of Detroit. And I am pretty sure you're NOT going to be thinking Toyota. Just saying...

      It doesn't take a moron to figure the point of a /. summary.

      • by shutdown -p now ( 807394 ) on Tuesday July 24, 2012 @08:50PM (#40759209) Journal

        Neither the summary nor the article don't really try to make any points, they just report on a specific fact. It's kinda telling that this fact immediately triggers a slew of apologetic posts. To take your example, it would be as if you wrote an article giving only the raw numbers about how Detroit fares today, and I would make a first post there along the lines of, "all you people trying to blame GM here are liars, it was Fiat all along".

        • You don't think the historical claims of global warming being behind the ice melt in Greenland have anything to do with the jump of comments?

          In your Detroit scenario, it would be like after years of bombardment that GM destroyed Detroit, an article comes out and someone points to what they think is significant about Fiat's roles.

      • Re: (Score:2, Insightful)

        Well, I can post an whole article and summary on the decline of auto manufacturing leading by to the decline of Detroit. And I am pretty sure you're NOT going to be thinking Toyota. Just saying...

        It doesn't take a moron to figure the point of a /. summary.

        Actually, one of my cousins gets about 1000 mpg with his plug-in electric car, using cheap GHG-friendly hydroelectric power to charge it, at about 1/10th the price of gasoline here in Seattle.

        We could always adapt. It's not that hard. He still drives to work. Just costs him less to do it.

        It's "adapt OR die" not "adapt AND die".

        • If I eat oatmeal, cooked on my wood stove, for fuel calories, I get about 3000 mpg. Humans get about 600mpg if they could digest gasoline (think, vegetable or nut oil). Oats yield 5 calories of output for each 1 calorie of FF input (including fertilizer, harvest, processing). Cooking on wood stove avoids use of FF for cooking (significant, for a low-cal input like oats). Wood for wood stove comes from downed trees, all my cutting is with an electric chainsaw, splitting is with a hand-hydraulic splitter

  • Hottest in 30 years, since 1889....er 40% melted away, 97%...er wait. What does this really mean?

    Oh, that 97% of the top layer of ice exposed to sun and warmth has melted. I am curious...how deep is this melt?

    Oh...think that a warm year + drought over North America might, just might lead to a little melting. In fact, if this is the worst drought in 60 years, but only the worst melting in 30 years. Maybe it's not so bad?

    LOL

  • I see a bright future for Greenland. Forget Spain or Greece, take a nice relaxing balmy beach holiday in sunny Greenland. That's where it's going to be at, if you are a property developer looking to build holiday accommodation, resorts, apartments, theme parks, restaurants and cafes. Get in now before the rush. And all that concrete and travelling there by air can only help make the dream come true sooner!
    • Re: (Score:3, Informative)

      Well, remember, Greenland was originally settled during a warming period that allowed Britain to grow wine, and the Viking inhabitants only died off when it reverted to colder temperatures.

      I recommend getting there by steamship. Maybe aboard the Titanic II?

      I'm sure it's safe.

    • by GodfatherofSoul ( 174979 ) on Tuesday July 24, 2012 @09:19PM (#40759469)

      You don't watch much SyFy do you? I guarantee a cheesy-looking, man-eating Yeti with a taste for swimsuit models (who will conveniently be waiting to be rescued by the rugged, misunderstood, loner biologist doing research in town) is slowing thawing out. We're just one summer break from a Greenland turning into BloodLand :(

  • So is this weather or climate? Because if it's weather isn't it just the equivalent to having an unusually warm winter in Eastern Europe or something? Did Greenland have an unusually warm winter or an unusually hot summer this year? That wasn't mentioned in the article. Perhaps someone at NASA is in the market for an oceanfront home? If global warming will reduce the market price for oceanfront property I'm all for it.

    • The analogy I've seen elsewhere is "loaded dice". If I roll the dice and it comes up 12, are they loaded? Can't say for sure. If I roll the dice and they don't come up 12 always, are they not loaded? How about if I roll the dice 360 times and get 100 twelves (instead of about 10)?

      One likely climate-vs-weather cause I have seen proposed is a change in "Rossby Waves": http://earlywarn.blogspot.com/2012/04/slowing-rossby-waves-leading-to-extreme.html [blogspot.com] This one thing would make weather "more extreme" simply

    • So is this weather or climate?

      Weather. A specific atmospheric condition (a heat dome - never heard that one before) moving over a specific area over a specific time is weather.

      Climate is trends and cycles in longer term averages of weather statistics and the probabilities of stuff happening.

      eg the el nino / la nina cycle and how that relates to the probabilities of storm frequencies or intensities is climate - any actual storm is weather.

  • Finally the Greenland will live up to its name [wikipedia.org]!
  • From the Article (Score:4, Interesting)

    by phantomfive ( 622387 ) on Tuesday July 24, 2012 @09:11PM (#40759407) Journal

    "Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."

  • by Anonymous Coward on Tuesday July 24, 2012 @09:23PM (#40759497)

    During a time when the US is facing its most serious drought since the 1930's, its no time to talk about ice sheets melting or global warming, just like its no time to talk about gun control just after 70 people get shot in a theater. Its not the right time to talk about it! You are welcome to talk about global warming in the middle of the mild winter, or droughts in the rainy season (whenever that is), or shootings and gun control when all is peaceful. A public pandemic is no time to talk about health care, and forest fire season is no time to talk about children playing with matches! People with vested interests could have their vested interests changed. That's just not right.

    • Or we could have emotions demanding completely useless and ineffective solutions that do more harm in the long run then any good perceived or not.

      The reason we wait until something has played down a bit is not because everyone will forget about it, but because the emotions have died down and you don't end up banning dyhydrogen monoxide simply because it is used in the process of making guns and ammunition and destroys millions of dollars of property each year.

  • by Grayhand ( 2610049 ) on Tuesday July 24, 2012 @09:51PM (#40759705)
    Everyone is really good at rationalizing specific data points like "it's part of a 150 year trend". The problem is there's world wide evidence and not just glacier melts. There's a measurable trend going back to the industrial revolution when the CO2 release started. It accelerated in the 80s as growth in third world countries kicked in. It's everything from glacier melting to weird weather and from sea level rise to a severe drought in the US to the worst one in Australia in several thousand years. What I keep hearing is every time a piece of evidence shows up is "I can explain that". At what point do we accept that all the "I can explain thats" add up to we've got a problem? Long term what we are staring at isn't a hot planet but one that overreacts to a spike in CO2 causing a worse ice age than the last one. Rationalizing is a little like sticking your head in the sand. Each rationalization is another inch. Eventually your head hits China and the planet is still warming whether you like it or not.
    • by drooling-dog ( 189103 ) on Tuesday July 24, 2012 @11:36PM (#40760333)

      You're right. It's always an incoherent attack on a particular observation, data point, or (ad hominem) scientist, while ignoring the great bulk of the evidence. With all of the corporate money being thrown around to sow confusion and doubt amongst the public, you'd think that the fossil carbon industry would at least attempt to construct a defensible, competitive climate model that takes account of this body of evidence and produces the result they (and thus conservatives generally) want. But, of course they don't. PR may not be any cheaper, but at least they can be confident of the results.

      If this is going to be a bona fide scientific controversy, then both sides have to be doing some compelling, quality science. So far only one side has.

  • Greenland used to be farm land. It was called, "Green" land for a reason. But then about 600 years ago the planet cooled and Greenland farmers had to abandon their land. Harsh, and no, it wasn't because of humans causing climate change. Rather climate change has happened on a regular basis in cycles over the last several billion years. Now it is warming up and can be farms again.

    The reality is that during periods of warming there was greater diversity. People need to stop focusing on climate change and focu

    • by khallow ( 566160 )
      While there's some question as to just how "green" Greenland was (there is speculation that the name was a marketing ploy), I agree it was better at some points in the past than now.

      People need to stop focusing on climate change and focus instead on the real problems like toxic pollution and war. Global Warming is a just a distraction.

      For example, consider desertification. As I understand, it destroys about as much farmland each year as would be lost to a roughly one meter rise in sea level, which is the towards the worst of the predictions for the end of the century.

      AGW wouldn't help in other ways, but poor farming practices are a much bigger factor.

    • Greenland used to be farm land. It was called, "Green" land for a reason. But then about 600 years ago the planet cooled and Greenland farmers had to abandon their land.

      Greenland's current ice sheet is over 100,000 years old. When people say "Greenland used to be green", they usually mean 450,000 to 900,000 years ago... not 600.

  • by hcs_$reboot ( 1536101 ) on Tuesday July 24, 2012 @10:16PM (#40759877)
    ...for the Greenlanders.
  • You keep using that word. I do not think it means what you think it means.

  • The first thing that the Governments can do is abolish daylight saving - we need less daylight not more.

  • by TheGoodNamesWereGone ( 1844118 ) on Wednesday July 25, 2012 @01:14AM (#40760813)
    Ummmmm, Greenland was named that because it used to be green back when it was first discovered. Even allowing for travel/investment brochure hyperbole. Just sayin'...
    • Well over 95% of the ice currently on Greenland was there when it was named. If not sea levels would have been significantly higher then and they weren't. If Greenland were to melt completely it would cause about 20 feet of sea level rise, that's 1 foot per 5%.

For God's sake, stop researching for a while and begin to think!

Working...