Hole in the ice

BremenAMSR-E080702crop.jpg The National Snow & Ice Data Centre in the US is issuing regular (monthly, though they might have to become more frequent soon) updates on the progress of this year’s Arctic melt season. Today they released their report for June, and like their earlier reports (accessed from the drop down menu top right on the page), it includes a lot of very interesting reading. Here’s a highlight:

June sea ice extents in 2008 and 2007 are essentially identical, and near the lowest values for June ever recorded by satellite for the Arctic.

They note that the spatial pattern of melt this year is very different to last year, with much less melting in the Chuckchi Sea (top left on the pic at top – click for a bigger version), and much more to the north of Greenland and the Canadian archipelago. But the big news is that this year’s melt season started much earlier than usual. Take a look at this graphic:200807NSIDCmelt2.jpg

The blue bits show the areas that start melting latest. 2007 was close to the long term average in that respect, and the difference with this year is striking:

This year, sea ice in the Beaufort Sea began to melt on average 15 days earlier than normal, and 15 days earlier than last year. Surface melt in the Chukchi and East Siberian seas was 6 days earlier than normal, and 14 days earlier than in 2007. In the central Arctic Ocean, melt began around June 9th, which was 12 days earlier than normal and 9 days earlier than the year before.

Even the areas where the ice still looks pretty solid (north of Siberia) started melting weeks ahead of normal. The next month is going to be extremely interesting. The odds are tipping my way again…

Note: my new favourite site for monitoring the current sea ice area is the University of Bremen’s imagery. I don’t mean to be disloyal to Cryosphere Today, which remains essential, but Bremen’s images are higher resolution, and to my eye make what’s going on easier to follow. If we could just get some of CT’s features at Bremen, and vice versa… 😉

[This post updated July 4 to reflect amended NSIDC graphic and text (see comments). Doesn’t look as bad as it did – but that’s not much cause for comfort.]

31 thoughts on “Hole in the ice”

  1. That’s an exciting and interesting post from NSIDC. Your post is of course interesting (ahem) but I read all about this over at NSIDC first. 😉

    I don’t think this changes the odds (they are what they are, the bet is a test of confidence of the observer), but it certainly gives reason to think you may win the bet. 🙂


    oh dear. 🙁

  2. Well, that is kind of like what one would imagine to be a melt pattern leading to a more-or-less complete loss. Just sayin’.

    Also, does anyone know what metric is used for onset of melt? Just the change in reflectivity, I assume, but I couldn’t see where they actually said so.

    That makes me wonder if there’s a change in reflectivity as melting intensifies, and if so whether that data would tell us anything useful.

  3. As it happens, the NSIDC updated that graphic last night, to take in data up to the beginning of July, and it changed the look completely. A lot of the green in the post above has disappeared. If I have time later, I’ll grab the new graphic and update my post.

    And Steve McIntyre at ClimateAudit has decided that the numbers already show that I’m going to lose my bet. This would be the equivalent of chartism as a method for predicting financial markets, presumably. Anyway, he manages to comprehensively complicate the statistics… 😉

  4. The new version looks a lot less dramatic. I’m guessing that where melt hadn’t begun yet it showed green because that was the latest date that data was available for. Confusing.

  5. What’s interesting about this isn’t the understandable error but the fact that NSIDC is now in such a flaming hurry to get this stuff up. Things used to be a lot more sedate in that neck of the woods.

    Actually the new plot still shows sharper melting than the others. Interestingly it most resembles 2006, which was headed toward a major new loss until a July cold snap brought it up short. Of course that could happen this year too.

    McIntyre seems to have hedged his bets, taking the opportunity to pontificate again about how of course he would take the IPCC’s advice on overall policy direction. Man is he transparent.

  6. I don’t think it’s an understandable hurry. They should have got it right before publishing. The infantile will jump on this. As I’ve recently said I’m back to not being sure what’ll happen.

    The good news: The previous version would have badly knocked Bitz’s contention that 2007 was an outlier and the ice should get back on track along the previous trend. At least the new version hold that hope open. 🙂

    I’d rather the transition to seasonally ice-free take decades, if it’s all the same to everyone else. 😉

  7. CW, I don’t think it holds that hope open at all since it’s palpably worse. Let’s not forget that this ice is also a lot thinner overall.

  8. OT: Does this paper ring a bell? I had never heard of it, which seems odd given the implications. The abstract:

    “The Late Cretaceous continental interior of Siberia: A challenge for climate models

    “Geological evidence from the Late Cretaceous continental interior of the Vilui Basin, Siberia suggests a far wetter, warmer, and more equable annual climate than General Circulation Models (GCMs) can reproduce. The disparity cannot be bridged by the uncertainties inherent in either the models or the geological climate proxies. This implies the mismatch is genuine and that either 1) we have systematic errors in the interpretation/calibration of the climate proxies, and/or 2) lack of full knowledge of the boundary conditions needed for GCM models simulations of this period, and/or 3) an insufficient understanding of the nature of the coupled atmosphere–ocean–biosphere system and its representation within climate models during warm climate epochs. If it is the third explanation, this would have important implications for the prediction of future climates and would suggest that we may currently be underestimating future climate change in such regions.”

    They appear to be leaning toward the third explanation, although it’s not entirely clear to me how the second one is different.

  9. This New Scientist feature from a few weeks ago discusses hothouse conditions at the Poles between 100 and 40 million BP. It’s behind a paywall, but here’s an interesting bit. Even suggests who to contact…

    There is yet another serious problem for climate modellers. The one place the models suggest did get cold during the hothouse episode is the interior of continents at high latitudes – regions like Siberia. This doesn’t fit with the evidence.

    In rocks from the late Cretaceous in Siberia, Robert Spicer of the Open University in Milton Keynes in the UK and his colleagues have found plenty of evidence for ferns and flowering plants, and even possibly the pollen of palm trees (Earth and Planetary Science Letters, vol 267, p 228). Their analysis suggests that at that time Siberia’s mean annual temperature was about 13 °C, rarely touching freezing even in the winter months. “All the climate models give you very, very cold continental interiors [at high latitudes] in the winter time, so cold that you would certainly freeze palm trees and kill them off,” Pierrehumbert says.

    One answer to this puzzle is to keep pumping up the CO2 levels. Models predict that the interiors of continents at high latitudes would not have frozen during the winter if CO2 levels were higher – but this means the tropics would have got even hotter.

    Huber has suggested a possible answer to this dilemma: what if much more heat from the tropics was somehow carried to the poles, keeping the tropics from boiling over. He and Ryan Sriver, also at Purdue, think they have found one possible mechanism.

    They studied conditions in tropical waters before and after the passage of present-day cyclones. They found that cyclones mix up the upper layers of oceans, moving heat downward. They argue that ocean currents then transport this heat towards the poles, reducing the temperature gradient between the tropics and the polar regions ( Nature, vol 447, p 577). Many researchers think the intensity, frequency and duration of tropical cyclones increase with higher temperatures. If so, the amount of heat transported to the poles by cyclones would increase greatly as temperatures rise. In a hurricane-ridden hothouse Earth, this could have kept the tropics below 35 °C, while the poles simmered in subtropical heat.

    However, Pierrehumbert thinks that the cyclonic heat-pump idea needs more work, and that explaining the warm interiors of continents remains a challenge. “This is now the most mysterious and toughest looking part of the problem,” he says.

  10. Steve, Gareth,

    The cloud paper I emailed to Gareth & Wayne Davidson recently mentioned evidence that the Arctic Ocean did not drop below 20degC (if I remember rightly). The paper was a study of cloud feedbacks and argued we may see cloud feedback ahead of model projections. I’ll post a link later when I’m back home.

    At present heavy cloud, high humidity, and high persistent GHG levels (CO2/CH4) look to me to be the best explanation for such extreme warming, rather than changes in atmos/ocean heat flux, where the incoming warm air is still subject to the sort of radiative losses that cool the winter Arctic now. The proposed cloud feedback has the advantage that it would be regional, so would not require CO2 levels that would imply tropical warming above proxy observations.

    I do recognise that the ice is thin and consequently there is much less volume. Indeed I still keep banging the drum of “mechanical factors” on this. Such mechanical instability will, I argue, augment and accelerate the thermodynamic processes.

    However over at Stoat in April (on the ‘kerfuffle’ thread) I posted about Bitz’s observation re consecutive minima and how we may not be at the point where this regime is broken. I think such a new regime of different behaviour is likely and when I saw version 1 of NSIDC figure 4 I did think that was such an indicator.

    However it seems we might not be at that point, and if Bitz is right on that, perhaps she’s right about the models. There’s been no reply from her or anyone else to my question about whether the models show the same crash in perennial ice as shown in Nghiem 2007 figure 3.

    There is research (ref below) that shows that the 1990s temperatures were not enough to maintain a seasonally ice free state, do we know for sure that a seasonally ice-free state would be stable now? There are problems with the conclusions drawn from simple model considerations of Small Ice Cap Instability: Michael Winton “Sea Ice Albedo feedback and Non Linear Arctic Climate Change” http://www.gfdl.noaa.gov/~mw/agu_chap.pdf See section II Elementary Arctic Climate Dynamics.

    To me another crash of 1 million below last year would reasonably be an unequivocal sign of a new regime. But a maintenance or recovery above last year will still leave some doubt. That will only be resolved with more time. Note Prinsenberg’s ARCUS assesment:

    From what I saw in the Amunsden Gulf and imagery I feel we will have the same extent as last year “as a rebound” but then lose a lot more the following year.

    Bitz’s idea that new records do not follow a record year is based on observation, but is connected to this notion of rebound.

    On balance I still think we’re in a fast transition to a seasonally ice-free state. But with regards this year, it’s still looking like single years are noise.

    Dorn “Sensitivities and uncertainties in a coupled regional atmosphere oceanice model with respect to the simulation of Arctic sea ice.” J Geophys Res. 2007; 112: D10118.

  11. That paper about cloud feedback in the Arctic. preprint, caution as far as I can see this is submitted to peer review but not yet published.

    3rd para to Steve above betrays a rushed lunchtime post, I should have started it with “So”, and should have noted that I asked the question of Bitz at RealClimate in the current Arctic thread.

  12. Well Bitz’s idea that “new records do not follow a record year” is about to be proved very wrong in the Antarctic. A record sea ice extent in 2007 will be smashed in 2008. So you’ll forgive me if I don’t put a lot of store in what Bitz has to say. I’m sure the feeling would be mutual.

  13. According to the NSIDC, “Arctic sea ice reflects sunlight, keeping the polar regions cool and moderating global climate. According to scientific measurements, Arctic sea ice has declined dramatically over at least the past thirty years, with the most extreme decline seen in the summer melt season.”

    So, shouldn’t the global temperature have risen then, over the past 11 years? http://bp3.blogger.com/__VkzVMn3cHA/SFs25eMZegI/AAAAAAAAAC8/pDT5GEKQTUA/s1600-h/11+Year+Temp+Data.bmp

    Given last year’s ice loss (albedo) how come late 2007 and 2008 have seen dramatic global temperature drops?

  14. Sidney,

    How many times must you be corrected before you spot the pattern?

    Well Bitz’s idea that “new records do not follow a record year” is about to be proved very wrong in the Antarctic.

    FACT: In the satellite record of the Arctic ice there has never been a new record in the year following a record September minima year.

    What Bitz has noted* is an observation from the actual data for the Arctic. The Antarctic is at the orther side of the globe!

    Furthermore Bitz is arguing that last year was an outlier that does not represent the start of a new regime in the Arctic.

    Given last year’s ice loss (albedo)…how come late 2007 and 2008 have seen dramatic global temperature drops?

    The Arctic isn’t the globe.

    *Ref: “Arctic Summer Sea ice 2007 and
    Other Arctic Extremes” Presented by Cecilia Bitz Atmospheric Sciences Univ. of Washington. Page 11.

  15. Thanks for the New Scientist reference, Gareth. The connection back to Huber’s work is interesting indeed. I wonder if what Ray means is that a result by a single junior scientist (Sriver is Huber’s grad student) needs more work as a matter of definition.

  16. Ok, Sid. Thanks for that graph. So take the ten year average – 1997/8 – 2007/8, and compare that to the average for 1987/8 – 1997-8. Which is higher. What does that show?

    I am prepared to accept any reasonably sized bet that the average for the years 2008 – 2018 will be above 97-’07. But I suspect that arguments about global figures will be rendered irrelevant by events long before then.

    Also worth noting that RSS and UAH numbers don’t include polar regions, so don’t/can’t reflect the Arctic warming. Hadcrut does to a certain extent, GISS more so. Some coincidence then, that you’re so keen to dismiss GISS…

  17. CW. Yes, ahem, I do think Bitz was talking generally about “new records do not follow a record year”. Think before you write Cobblyworlds.

  18. Gareth. I accept your point about the graphs, but you’re forgetting that GISS use proxies for Arctic temperature! And anyway, my point, made quite clearly Gareth, was that ice loss from the Arctic over the past few years (and especially last year) has done nothing to increase global temperature. One can only conclude that it might even be lower than it is now if it weren’t for the ice loss then. We can only reliably measure climate change through the troposphere and the oceans – for obvious reasons. Many will take your bet. With an inactive Sun right now, that could result in a Maunder-type minimum, then you are being careless with your money!

  19. CW. Yes, ahem, I do think Bitz was talking generally about “new records do not follow a record year”. Think before you write Cobblyworlds.

    Prove it.

    Because I have a copy of her conference presentation and she is clearly referring solely to the Arctic. As indeed is William Connelly who noted that very same behaviour in his blog “Stoat”.

  20. I’m sorry, guys, but I suddenly found myself laughing – albeit somewhat insanely.

    I feel like I’m reading a transcript from passengers arguing about the speed at which the Titanic is steaming, whether one engine or three are operational, it’s suddenly gone into reverse, or if momentum alone will carry us to an inescapable destiny.

    That’s not to say the discussion isn’t worthwhile, but is anyone else getting that sinking sense of comédie noir?

  21. [Mad cackles off stage]

    Sonny, you’re just an alarmist.

    But if you want to help me enlarge my veggie garden…

    (And it’s reasonably safe to ignore Sid. He has just the one remarkable ability. He can read anything and misconstrue it in accordance with his preconceptions. It’s a talent. He should be a politician.

  22. Titanic? It’s a bit too early to remake that.

    How about:

    “Dr Strangelove.
    or how I learned to stop worrying and love Peak Oil.”
    “Ice Station Zebra: 2015”
    Shorter and wetter than the original.

    I often find myself laughing, I’ve come to the conclusion that our entire civilisation is best viewed as a farce, a-la “Carry On” series:

    “Carry On Over The Precipice.”

  23. Actually, Gareth, I was going to ask you to help me with *my* vegie patch.

    I’ve just purchased a rather nice property outside Oxford, towards Ashley Gorge, an ex-nursery with a zillion herbs, huge vegie patch, and two tunnel homes. Thanks for your advice on that, BTW; I’m hoping the tunnel homes, one of which is heated, will suffice in the frost (now if I can just figure out how to heat it using solar panels or a wind generator… Hm, next project).

    It may not be the biggest life raft, but after a morning reading Ross Garnaut’s interim report, now I’m back in Aus I’m counting the days until we can move into our new home across the Ditch.


  24. Laugh? Oh yes! Gareth said this on Poneke’s: “And if the world is not warming up, please explain why the rate of ice melt in Greenland and Antarctica is increasing, and why the Arctic sea ice looks headed towards another record summertime low”. Clearly associating warming with ice melt, of course. Yet he won’t answer a simple question: ‘Is Antarctica warming or cooling overall?’ But it gets worse for Gareth, as a Dutch team have recently published a paper stating that the Greenland melting cycle exhibits no trend in the last 17 years. And on top of all that it looks like he won’t be winning $40 on his bet to send to Oxfam after all. I’m enjoying watching the Arctic ice NOT melting over on the Cryosphere site! Is it my imagination or is 2008 bang on the average? http://www.climateaudit.org/wp-content/uploads/2008/07/seaice38.gif
    Oh, laugh!

    Gareth. Do you remember saying this: “reality will come back and bite you on the bum.”?

  25. Actually, Sid, the “Dutch paper” you refer to says no such thing. And reality will bite you on the bum, to be sure. I would prefer to lose my bet, don’t forget.

    I will grant you that the CT anomaly today is above the same time last year – but there’s still plenty of the melt season to go. This year’s ice is thin… Still 50/50 in my book.

  26. Bang on the 2002-8 average, that is, which Sidney will know is below the 1978-2000 average if he has been watching the cryosphere site. So the Arctic sea ice is melting, and more than it used to, although not as much as last year. If that continues to be the case I’ll be happy to call 2007 a blip.

  27. Gareth. I’m sure you’ll be the one who is bitten, and I’ll be here to remind you of all that you have said. Oh, and I’ll still be asking you whether the Antarctic is warming or cooling overall.

  28. Gareth; “Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.”

    So, I hope you don’t mind if I’ll go with Motl on this one!

  29. Thanks, CW. Can’t see the full report yet, but the balance of predictions is perhaps a bit more skewed towards more ice than last month’s. Meanwhile, there is just a hint of a speed up in the melt. The CT anomaly is down to half a million more than same time last year.

    The Antarctic extent is also interesting. The anomaly has dropped to zero – not much new sea ice has formed in the last month.

Leave a Reply