Unnatural variation

The oldest sea ice in the Arctic is thousands of years old, and in places it’s a hundred meters (330 feet) thick, locked in ice shelves which cling to the farthest northern coasts. The most extensive Arctic ice shelves are in Canada along the coast of Ellesmere Island. In fact they define the coastline there, forming part of the permanent geography of that land.

At least, they used to.

The coastline of the Canadian Arctic is changing as Arctic ice shelves disappear — also reported here.


Recent (ice shelf) loss has been very rapid, and goes hand-in-hand with the rapid sea ice decline we have seen in this decade and the increasing warmth and extensive melt in the Arctic regions,” said Ted Scambos, lead scientist at the National Snow and Ice Data Center. He added that Arctic shelves are old and their rapid loss underscores the severity of the warming trend scientists see now relative to past fluctuations such as the Medieval Warm Period. In fact these ice shelves have been in place for 3,000 to 5,000 years. Now they’re vanishing, right before our eyes.

Derek Mueller of Carleton University and Luke Copland from the University of Ottawa report that ice shelves have declined “considerably” almost every summer since 2005.

Why would such a change occur, one definitely not seen for at least 3,000 years and possible much longer? Could it be the heat?

I’m sure that some fake “skeptics” will soon come along to explain how it can’t possibly be man-made global warming.

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31 responses to “Unnatural variation

  1. First guess at a “skeptic” response:

    One look at that temperature graph reveals that that there has been no significant warming since 1981!

    Second guess:

    If you include a 60 year cycle, the warming rate is much less than your alarmist trend line suggests.

    Third:

    Nunavut’s population is booming, 40% in 15 years! Urban heating can explain the cycle-corrected warming rate.

  2. Tamino, could you please compute the ratio of the systematic variation you show to the standard deviation of the residuals? it seems by eyes that it is not that significant.

  3. “I’m sure that some fake “skeptics” will soon come along to explain how it can’t possibly be man-made global warming.”
    Gatekeeper Tamino, why ask such silly questions? Of course it’s the heat! Although it’s clear Ellesmere island measurements are severely suffering form UHI-effect from all those subsidy sucking scientsts flocking there. There’s a picture of the station that explains it all.

    But you should know by now that it’s just natural variation. Cycles and oscillations, the passage of the earth through the Galactic spiral arms or our invisible twin planet Elenin, pick one or more, I don’t know. Come on, CO2? It’s just a trace gas and plants are starving!! Watervapor is a much more important GH-gas and it is declining.

    Whatever it is, it is impossible to think it could be because of our influence, how arrogant is such a thought -that we can influence nature- anyway?! Most importantly, earth has been much warmer in the past, so the current warmth says nothing. There weren’t people around 30 million years ago, don’t you get it?!!

    See, it’s just borne out of our religious beliefs that we are to blame for everything bad that is happening. Besides the green movement would like you to believe AGW so they can get bigger grants. Others like Al Gore get rich preaching doom and he’s using more energy then all Americans combined. It’s true, I read that somewhere. Oh, and Mike Mann who’s schtick has been proven to be an utter falsehood by St.McIntyre and independently verified by Dr. Wegman.

    But if the fatally flawed models happen to be correct for once then we can’t do anything about it. Can you even imagine a world without fossil fuel cars, monster flatscreen tv’s and 200 gram prime meat flown in from Argentina with every meal? Even if we cut back, then others will increase there fossil fuel use. Our grandchildren will be so much richer then us anyway, you know: exponential economic growth, it has always been that way. So they can solve it easily without completely wrecking the economy.

    There, Tamino, it’s settled, I’ve just proven it. Who’s the “fake” skeptic now, eh?!

    BTW, did you know earth is cooling since 1998? We’re going to a new ice age and we need to burn as much fossil fuels as possible to keep the planet habitable.

  4. I’m sure that some fake “skeptics” will soon come along to explain how it can’t possibly be man-made global warming.

    Undoubtedly some will do just that. It’s been interesting lately to observe how denialist agitprop has largely shifted from “no warming” to “unstoppable warming.” It’s all natural cycles, or sun, or decadal oscillations, or just those evil scientists, or–something.

    Maybe it’s to do with the warm North American summer this year, but just maybe the “no warming” option is becoming too untenable to work, even among the denialist faithful. We’ve had a very low sea ice minimum, we’ve had massive droughts and heatwaves, and now we’ve got this report from the Carleton U geographers (which has been picked up very widely indeed, despite the fact that it appears not to be associated with a paper in the literature, so far at least.) And we’ve had a couple of years of denialists predicting cooling and sea ice recovery.

    Just maybe the BS has worn a bit thin. (Yes, I know–I’m an optimist.)

  5. For those interested, there’s an interview with Dr. Derek Mueller as part of this CBC story on the Ellesmere ice shelf collapse:

    http://www.cbc.ca/news/canada/north/story/2011/09/28/north-ice-shelves.html

  6. Becareful with your conclusions. The Hunt ice shelf contracted 90% from 1906 to 1982 [vincent et el 1995].

    This happened before 390 ppm co2.

  7. Some prominent scientist (Richard Alley?) testified before the US Congress not too long ago and summed it up in a way even his audience that day could understand: “It gets warm… ice melts.” Anyone know who it was?

    Yet the deniers would have us believe that both the observed temperature increases and the observed melting are wrong. Or perhaps they believe that it can warm without melting ice, or ice can melt without a rising temp, or …?

  8. Luke was one of my undergraduate supervisors, he’s put in a lot of work on the subject and has even written a book on ice shelves with Mueller (not sure if it is released yet?). Anyways some of the ice shelves they’ve investigated have collapsed after 5,000 years of relative stability. If you want to talk Canary in the coalmine, look at the Ayles Ice Shelf amongst others. These survived the “supposed” high latitude warming during the MWP and RWP but have been eradicated over the last 10 years. In Antarctica the story is just as dire.

  9. This topic is also dicussed at Nevens Arctic Sea Ice Blog:
    Canadian Ice Shelves Breaking up at High Speed – http://neven1.typepad.com/blog/2011/09/you-do-it-to-your-shelf-.html

  10. Pierre, not the Hunt ice shelf:

    “The entire northern coastline of the island appears to have been fringed by a continuous ice shelf 500 km in length as late as the turn of the century
    [Vincent et al., 2001]. This large Ellesmere Ice Shelf progressively disintegrated over the course of the twentieth century, and today only 10% remains [Vincent et al., 2001], the largest remnant being the Ward Hunt Ice
    Shelf (Figure 2).”

    Yes, it was before 390 ppm co2, but it was nonetheless coincident with global (and regional) warming of incompletely attributed causation.

  11. “The oldest sea ice in the Arctic is thousands of years old, and in places it’s….”

    I thought Ice shelves were floating glacier ice not ‘sea ice

  12. Becareful with your conclusions. The Hunt ice shelf contracted 90% from 1906 to 1982 [vincent et el 1995].

    Do you have a link for this? I’ve done a bit of googling and have found a couple of papers that cite more recent work by Vincent (2001) that does not appear to support your claim at all.

    And of course the canadian scientists who are quoted above quite obviously disagree with your claim.

    Can you tell us exactly which denialist site you cut-and-pasted your claim from?

    TIA …

  13. And if, like me, you do not and have not lived in the Arctic, but feel a visceral connection with the luminous darkness of that frozen land and want to understand something of what we and all who follow us are losing, read ‘Arctic Dreams’ by Barry Lopez, written, mercifully, before the current tragedy became manifest.

  14. Pierre,

    Luckily I caught your post before posting what I drafted last night. So I’ve extended it to address your ‘point’. Be careful with your insinuations. ;)

  15. Tamino,
    this post at WUWT is SO stupid it is just asking for you to rip it to shreds

    http://wattsupwiththat.com/2011/09/29/warming-island-greenland-sea-regional-climate-and-arctic-sea-ice-reconstruction/

    Like… its mathturbation at its worse. Making a regression model based on 13-month running means of sea ice index and the temp anomaly… its just… anyways

    • Mosher nails him. Middleton’s response can be boiled down to “doing it right would’ve been too much work, but I stand by my conclusion”.

      • And lo, and behold–there’s a reference to Vincent and the 90% decline of the former Ellesmere Shelf, too.

      • Ah, yes, it’s referenced in the article linked by Tamino in his post.

        So Middleton’s game is to pick a quote from the piece published by the canadian researchers and use it to “prove” that the conclusions reached by said researchers is wrong.

        Interesting, ain’t it?

  16. Of course, Middleton can’t bring himself to quote this as well:

    Copland said mean winter temperatures have risen by about 1 degree Celsius (1.8 degrees Fahrenheit) per decade for the past five to six decades on northern Ellesmere Island.

    While pierre plays dodgeball by stating …

    This happened before 390 ppm co2.

    Well, 290 ppm co2 was left behind as well …

  17. It is worth noting that the Canadian Arctic Ice Shelves are reflective of more standard ice caps in the Canadian Arctic like Penny Ice Cap or Devon Ice Cap. These ice caps are sensitive primarily to air temperature, and of course insensitive to sea surface temperature.

  18. And it is not just the ice shelves, research by canadian scientists (Gardner et al. 2011, Nature) are finding that the loss of ice from the Canadian Arctic Archipelago is increasing rapidly and making a notable contribution to sea level rise. Their paper is titled:

    “Sharply increased mass loss from glaciers and ice caps in the Canadian Arctic Archipelago”

  19. Not sure if this is a good place to ask, but I was trying to read one of your old posts you linked to “red-white-blue-noise-that-is/” from Jan 2007 and I couldn’t access it. Do you know what happened to it? Thanks!

  20. There appears to be a ten year lag between temperature and disasters.

    • “There appears to be a ten year lag between temperature and disasters.”

      Surely this has to be a Poe…?

      • Steve Metzler

        No, not a Poe. Doncha know that according to the denialosphere, there has been no statiscally significant warming for the past 10 years? Now that there *has* been statiscally significant warming since 1995 (remember that infamous BBC Phil Jones interview in 2009 where the deniers got to choose some of the questions?), they had to move the goalposts to 2001.

  21. About Arctic ice (but not ice shelves) … NSIDC, UB, IJIS and CT September means are now out. Tamino’s quadratic 4.6 was right on for NSIDC extent.

    I plotted the 5 time series together in one graphic posted over at Neven’s:
    http://neven1.typepad.com/blog/2011/10/september-2011-sea-ice-extent-looking-back.html

  22. Tamino,
    How do we correct for autocorrelation when using running means? Is there a way to do so? Say I was using 11-year means (or 121 months, whichever) and they seemed to *appear* to be highly correlated, my r2 would be very inflated just because i’m correlating running means, is there a way to correct for this and get an estimate of the fit?

    [Response: Yes. It's a bit of a long story, but I'm working on a related post. But -- in most cases the best way is *not* to do your analysis with running means, but with the original data.]

  23. Ice shelves aren’t “sea ice.” Sea ice is floating ice.

  24. Possibly worth a look:

    http://www.nonlin-processes-geophys.net/18/295/2011/npg-18-295-2011.pdf
    Nonlin. Processes Geophys., 18, 295–350, 2011
    http://www.nonlin-processes-geophys.net/18/295/2011/
    doi:10.5194/npg-18-295-2011
    Extreme events: dynamics, statistics and prediction

    Abstract. We review work on extreme events, their causes
    and consequences, by a group of European and American
    researchers involved in a three-year project on these topics.
    The review covers theoretical aspects of time series analysis
    and of extreme value theory, as well as of the determinis-
    tic modeling of extreme events, via continuous and discrete
    dynamic models. The applications include climatic, seismic
    and socio-economic events, along with their prediction.
    Two important results refer to (i) the complementarity of
    spectral analysis of a time series in terms of the continuous
    and the discrete part of its power spectrum; and (ii) the need
    for coupled modeling of natural and socio-economic sys-
    tems. Both these results have implications for the study and
    prediction of natural hazards and their human impacts.