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Huge Arctic Ice Shelf Breaks Off

knarfling writes "CNN is reporting that a chunk of ice shelf nearly the size of Manhattan has broken away from Ellesmere Island in Canada's northern Arctic. Just last month 21 square miles of ice broke free from the Markham Ice Shelf. Scientists are saying that Ellesmere Island has now lost more than 10 times the ice that was predicted earlier this summer. How long before the fabled Northwest Passage is a reality?"

20 of 736 comments (clear)

  1. From TFA... by capnkr · · Score: 3, Informative

    Ellesmere Island was once entirely ringed by a single enormous ice shelf that broke up in the early 1900s. All that is left today are the four much smaller shelves that together cover little more than 299 square miles.

    So this is a process that has been going on for ~100 years now? And that means it is indicative of, or news because... ???

    Nothing to see here... (except my dwindling karma... ;) )

    --
    "...there are some things that can beat smartness and foresight. Awkwardness and stupidity can." ~ Mark Twain
    1. Re:From TFA... by flaming+error · · Score: 5, Informative
      Looks like you picked an excerpt that, posted out of context as you did, suggests no short term change. But here are the paragraphs that follow (emphasis mine):

      Martin Jeffries of the U.S. National Science Foundation and University of Alaska Fairbanks said in a statement Tuesday that the summer's ice shelf loss is equivalent to over three times the area of Manhattan, totaling 82 square miles -- losses that have reduced Arctic Ocean ice cover to its second-biggest retreat since satellite measurements began 30 years ago.

      "These changes are irreversible under the present climate and indicate that the environmental conditions that have kept these ice shelves in balance for thousands of years are no longer present," said Muller.

      During the last century, when ice shelves would break off, thick sea ice would eventually reform in their place.

      "But today, warmer temperatures and a changing climate means there's no hope for regrowth. A scary scenario," said Muller.

    2. Re:From TFA... by McGiraf · · Score: 4, Informative

      "can sail around the North of Canada."

      nope, they will sail in Canada, not around.

  2. Re:1906 by vux984 · · Score: 5, Informative

    YES! How long until it is 1906 again?

    The 'fabled' northwest passage is a shipping route linking east to west, navigable by normal cargo carrying ships.

    The northwest passage, which obviously existed since well before it was first crossed in 1906 by Amundsen, and still to this day, is a hazardous journey requiring an expedition and specialist ice breaker ships to cross.

    Should enough ice melt that it actually becomes usable as a shipping route, then at least the 'fabled northwest passage' will be reality.

  3. The Northwest Passage is open by Jon+Abbott · · Score: 4, Informative

    How long before the fabled Northwest Passage is a reality?

    From what I read the other day, it is open now...

  4. Re:1906 by Rei · · Score: 5, Informative

    The thing is that before we paid much attention to this stuff, there was ONE real model that predicted a global temperature increase: global warming. It was not ignored before because "the man" was trying to hide science, it was ignored because there was NO effort to show an actual cause and effect relationship.

    Spoken like a person who's never read a paper on the subject. The study of climate change is part models and part real-world data gathering and testing. Even among models alone, there are *many different* models, most on particular aspects of climate forcing and impacts, not the more famous global models. There is not one "model". And it wasn't ignored, by any standard; it's been an active ongoing research topic in the scientific community for decades. Peer review is the judge, not public opinion.

    This becomes embarressing when things like the carbon retention of the Sahara are studied, as we discussed weaks ago, and suddenly billions of tons of carbon disappear from the air in our models, but the temperature hasn't changed at all.

    Waht arr yoo talkng abowt?

    The reason this worries me is that, while fighting pollution and emissions is never a bad thing, we could very well be ignoring the elephant in the room, simply because the global warming discussion has become so political, (and that's the activists faults, not the scientists). What if, although our carbon certainly doesn't help, most of this is due to cyclical sun output?

    No. Read section 2.7, which summarizes pretty much every peer-reviewed paper published on the subject. Not even close. I mean, seriously -- did it never occur to you that maybe, just maybe, we have observatories and satellites studying in detail essentially every thing the sun does, in addition to all kinds of long-term proxy data?

    You know what caused the onset of the iceages? North and South America connected at Panama, cutting of the Pacific-Atlantic currents, which cooled the entire Northern Hemisphere.

    Ice ages happen regularly, on the order of tens of thousands to hundreds of thousands of years, along the lines of Milankovitch cycles. The Isthmus of Panama formed once, three million years ago.

    --
    Do you work at Taco Bell? The guy at the drive-through said that to me last night.
  5. Re:1906 by FudRucker · · Score: 3, Informative

    its called the albedo effect, the more ice melts the more blue open water absorbs heat which melts more ice (rinse & repeat) it can very well become an accelerating cycle...

    http://en.wikipedia.org/wiki/Albedo

    --
    Politics is Treachery, Religion is Brainwashing
  6. Re:1906 by techno-vampire · · Score: 3, Informative

    Clouds are not water vapor. They are formed of droplets of water (or sometimes ice) suspended in the air. As an example, fog is just a cloud at ground level. Clouds do, of course, reflect light, but don't act as a greenhouse gas. The various ways water vapor affects temperature are many and complex; so complex, in fact, that none of the computer models even pretend to take it into account because the formulas would take far too long to solve. Which, BTW, is one reason the computer models are unable to predict what's going on with any pretense of accuracy.

    --
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  7. Re:Confused by HiThere · · Score: 4, Informative

    Yes, the water is warming. Most of the current rise in sea level is due to the water warming, and thus expanding rather than to ice melting. That won't be significant until Greenland goes. Floating ice melting doesn't change the sea level, but merely absorbs the heat required to melt it. This is significant for absorbing energy without raising the temperature. But after the floating ice melts, then the seas can raise their temperature without the hindrance of needing to melt ice. (Note that this is also a block the other way to water cooling.)

    A given volume of water can hold considerable more thermal energy than the same volume of air at the same temperature. As a result the oceans act as a ballast on the thermal variations...but as they warm, the balance point of the scale shifts. It takes a long time to warm the oceans, and then it takes a long time to cool them. This is important in understanding climate change.

    Note also that warmer air can hold more water. This is important as a thermal transport mechanism. (I'm not a climate modeler, so I can't understand why this would turn some places into deserts...but I've seen complex interaction of subroutines, so I'm not surprised that things like this happen.)

    But it's not that either the air or the water is warming, they both are. Just at different rates, and with differing stability.

    --

    I think we've pushed this "anyone can grow up to be president" thing too far.
  8. Re:The Climate Change Guys Will Have a Field Day.. by Coryoth · · Score: 3, Informative

    You understand of course that extra energy in the system causes larger fluctuations right? The global average will increase, but so will the variance. Your colds will be colder, and your hots will be hotter.

    That's not a prediction of the IPCC, who gather together and summarise the peer reviewed literature. Climate is variable because there are a lot of things that effect it, from solar influences, to the La Nina/El Nino cycles. Regional variation is greater than global variation. Due to that variation we can still expect extremes to occur: some years are just very cold (for a number of factors not related to anthropogenic warming), and some are hot, and that will continue, regardless of warming. However, as noted in IPCC assessment reports (TAR WGI 9.3.6):

    ...a warmer mean temperature increases the probability of extreme warm days and decreases the probability of extreme cold days. This result has appeared consistently in a number of more recent different climate model configurations.

    In other words, individual cold days or years are not evidence against global warming, since they may well be a result of natural variation caused by other factors (and would have simply been even colder without global warming). To count as notable evidence against global warming you would need a significant sustained cold spell (5 to 10 years at this point). However, extreme cold days or years are not predicted effects of global warming. They may well happen, but there isn't any significant evidence that they are caused by global warming.

  9. Re:1906 by operagost · · Score: 3, Informative

    If the carbon dioxide makes up only 0.04% of the atmosphere (which it is), increasing it to 0.05% won't make a difference in the water vapor.

    --

    Gamingmuseum.com: Give your 3D accelerator a rest.
  10. It's bogus and they know it by MarkusQ · · Score: 3, Informative

    The "ice cover in the arctic is growing" claim is bogus, and they know it (or should). It keeps coming up and people point out that even the authors of the claim now say it's bogus (see linked thread) but the same claim keeps coming back, generally worded the same way ("the real inconvenient truth is that the ice cap is growing" or some such).

    I used to think it was just cluelessness, but I'm starting to suspect trolls.

    --MarkusQ

  11. Re:About weather changes and global warming... by SeniorDingDong · · Score: 5, Informative

    These are really really rehashes of thoroughly debunked arguments. We already know that solar output effects the energy that the Earth absorbs, we observe the output of the Sun directly, we know exactly how different solar output changes from year to year. We know the variability between solar output during solar output peak and trough -- it's 0.1% The total solar forcing can be calculated directly it's 237 Watts/M^2. So from sunspot peak to trough the forcing changes by .24 watts/M^2. We know the effect of greenhouse gas change (in particular CO2) since pre-industrial times on forcing. It's 2.43 watts/M^2 see for example The 2001 IPCC Report.

    It is true that solar output is high especially high for the past 80 years see solar variation but even the change between now and the Maunder Minimum (.2%) does not compare to forcing from greenhouse gasses.

  12. Re:1906 by YttriumOxide · · Score: 5, Informative

    Many possible reasons, but almost certainly NOT the sun's output... if the sun had that much "immediate and direct" effect on our temperatures, we'd likely not be alive to be discussing it on slashdot (the first "big spike" would throw us up over the boiling point of water)

    Also, please, repeat after me: "Local weather and daily temperatures do NOT show ANYTHING useful in Climate Models!". Longer term trends (in weather and temperature - e.g. Climate) are what counts (and even then, you still need to take in to account much larger areas also - your small patch of the world might be 2 degrees colder over the next 10 years, but if the rest of the world is 4 degrees warmer, you're just an interesting data point).

    --
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  13. Politicians love Global Warming by falconwolf · · Score: 3, Informative

    Not in the US. Many Republican politicians deny, or belatedly acknowledge, Global Warming. Mike Huckabee, I think but I'm not sure, speaking at the convention intimated Obama wants people to make sure their tires are properly inflated.

    Many scientists love it because they finally get some of the spotlight and almost all scientific disciplines can be somehow linked to global warming. Just work GLobal Warming into your research title and it becomes trendy and "important".

    That can work both ways, one groups of scientists getting big study grants for saying how bad Global Warming is while another group can get big grants also for disproving Global Warming. I haven't seen many of the later though.

    Falcon

  14. Re:1906 by silentcoder · · Score: 4, Informative

    Intriguing,
    Here in SA we had a huge problem with plastic bag litter. So much so that one MP described them as 'our new national flower'.
    A law was passed - it didn't ban bags, but it DID require them to be made at least 0.5 microns thick - meaning they are reusable (the older 0.3micron thin ones tended to tear if you use them more than once). This of course, costs money, so they ALLOWED (didn't require but in practise everybody did it) the shops to charge the price difference back to the customers.
    That means you pay about R0.40 for bag - but suddenly, people KEEP the bags, and reuse them as many times as possible because those fourty-cent charges add up.
    The result it that plastic bag litter has become notably less common in South Africa, they are a valuable commodity now. People tend to be so terrible they won't even avoid littering public parks out of caring for shared resources for the community - but they will damn well do it if it means not throwing away their own personal money.
    Sorry - if giving people an economic incentive not to throw their trash in the public park to strangle birds and fish (and yes, human children !) is 'telling them how to live' then I'm all for telling people how to live in some cases.
    Note also: I am NOT a fan of my government, my posting history will show how extremely critical I am of them in general - but where a well thought out plan has given a genuine benefit to the entire nation I will also give them fair credit.

    PS. Now if only we can find a way to give people an economic incentive not to throw ciggarette-butts, coke-cans, used-condom and broken beer bottles in the parks.

    --
    Unicode killed the ASCII-art *
  15. personal carbon credits by falconwolf · · Score: 3, Informative

    I don't know if you're being, or trying to be, sarcastic but there's a debate going on in the environmental communities on whether carbon credits are good or bad. Some saying are that they can help reduce reliance on fossil fuels. Others say people are just out for a quick buck. Still others say carbon credits are just a "feel good" measure, people can buy credits but then won't adjust their lifestyle to have a smaller carbon footprint.

    As I see it, carbon credits can be all of them.

    Falcon

  16. Re:1906 by OriginalArlen · · Score: 4, Informative

    You seem to be mixing up what you personally know with what it known by others. Believe it or not, some people know more about this than you do. The "fact of the matter" is that we know perfectly well what is causing the warming; numerous detection and attribution studies have unambiguously and robustly identified the cause of warming to be human emissions of CO2.

    --

    Everything I needed to know about life, I learnt from Blake's Seven
  17. Sigh. This meme is very old and very wrong... by TapeCutter · · Score: 5, Informative

    "We also know that water vapor soaks up 25 times as much heat as CO2, and that there's a lot more of it, especially over the oceans. Of course, the Global Warming Industry doesn't mention this, because it would make people wonder how much effect CO2 really has, except over cold deserts."

    You have been misinformed by the opposing "industry", scientists pretty much ignore water vapour for a very good reason. The atmosphere is saturated with water vapour. That means that the only way to change the amount of water vapour in the air is to change either the temprature or pressure of the atmosphere. In other words water is a feedback in a changing climate.

    Now what the anti-GW "industry" never mentions is a little thing called the dew point that explains why dew drops form all over the world every night, even in deserts. In a (globally) stable climate you can pump as much H2O as you like into the atmosphere and all that will happen is that it will fall out as rain/dew over the next few days.

    Here is a short list of some other old and tiresome misinformation that is midlessly regurgitated every time GW is mentioned...

    Climate change on Mars/Jupiter
    Sunspots.
    Cosmic rays.
    Volcanos emit more CO2 than mankind.
    No warming since 1998.
    Global cooling was all the rage in the 70's.

    There are many more but the point here is that people simply spout off what they read in the opinion pages without having a fucking clue as to what they are talking about and a complete lack of desire to find out. They assume that the thousands of scientists that make up EVERY national science body on the planet are lobotmised fools who haven't got a clue about what they have spent a good portion of their lives studying.

    A couple of minutes googling would have busted the ridiculous myth that you are propogating. If you or anyone else reading wants to be treated as a skeptic and not a 'denier', then act like a skeptic. Go and question your own assumption and try and prove yourself wrong. When you fail to do so then you may just be onto something worthwhile and ORIGINAL. Picking out pre-spun factoids that happen to fit your worlview is nothing less than the triumph of politics over science.

    Disclaimer: I picked on you because I was looking for the H2O meme and you were the first one I saw. If you are interested in some genuine science I can give you some links but I suspect your mind is made up and firmly closed.

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  18. Re:1906 by TapeCutter · · Score: 3, Informative

    "We should all just pray that we're not near any of the tipping points commonly talked about."

    Less than 10yrs ago when climate scientists were predicting one such "tipping point" would likely be an ice free summer artic by the end of the century, they were ridiculed in the press, in the halls of power and on slashdot. Yet today even the most conservative of scientists are predicting it will be ice free by mid-century and moderates are predicting "within a decade".

    Current modelling says that an ice free artic will speed up the warming in the N. Hemisphere causing drought conditions in the US mid-west and southern Europe, here in Australia we are coming to grips with what is being called a "permenant drought" that has seen our grain harvests halved for the last 10yrs (2005 was the only exception).

    "Sometimes I really worry that we've all had it too good for too long and a much grimmer future is just over the horizon..."

    I hope your wrong (especially since I'm about to become a grandad) but GW is just one of many signs that we are racing toward a global population crash of biblical proportions.

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.