The Guardian’s ridiculous claim of 75% Arctic sea ice loss in 30 years – patently false?

Well, with a headline like that you know I’m talking about denialist nonsense, and yes its WUWT again. What they are foaming at the mouth about is Jarvis Cocker: the iceman cometh but not the article, rather a factoid at the end:

Of the Arctic sea ice, 75% has been lost over the past 30 years. Last year saw sea-ice levels plummet to the second-lowest since records began. It is estimated that the North Pole could be ice-free in the summer within the next 10-20 years

Understanding this fairly simple piece of text proves to be beyond the Minds over there. 75% is a lot, and ice area or extent hasn’t declined by that much, so the obvious variable to look at is volume, which has declined more steeply. And indeed, if you look at the PIOMAS-based Arctic Sea Ice Volume Anomaly, version 2 you’ll discover that the September minimum has indeed declined by the reported amount.

So: how is it possible to be so stupid as to not guess this yourself? If you start from the bad-faith position that the Grauniad as lying, then you probably won’t even look. And if you’re so used to denying the ice change, then you’ll then further mislead yourself and your readers by deliberately looking at the change in annual extent rather than the September minimum, which is the one that people are far more interested in.

The very second commentator manages to guess right: I think the argument is about sea ice volume rather than area/extent but even with this clue AW still fails, replying The original article… does not contain any discussion of ice volume. I double checked. But by this point I think he has realised he is lying, because of course the original article doesn’t specify extent, or area either. Indeed the original article is unclear; but when there are several interpretations, one of which agrees exactly with the numbers, it doesn’t take much sense to realise which was the right one. Commentator number three finds the second flaw in AW’s stuff: that he has deliberately used annual rather than minimum. But neither 2 nor 3 has the wit or industry to find the actual numbers from PIOMAS.

Sadly, the usually sensible Nick Stokes manages to find the correct source for the numbers but then (mislead by the contrived lead-in of AW’s post?) fails to read them properly.

A little while later (after a pile of content-free Grauniad-bashing) JohnB finds the right answer and supports it with number from thinkprogress. AW doesn’t like this and in reply says some spurious nonsense and one plausible thing, viz quoting Julia Slingo: She also said that suggestions the volume of sea ice had already declined by 75% already were not credible. “We know there is something [happening on the thinning of sea ice] but it’s not as dramatic as those numbers suggest.” We need to pause here for a moment to contemplate the irony of AW taking as gospel the words of the UK Met Office’s chief scientist. This oddity can be explained in this way: she is saying something he wants to hear. However, AW still isn’t thinking straight: the Grauniad can only be reporting what the numbers say, not the One True Reality that inhabits JS’s mind. So when AW says “Slingo said the 75% loss for volume isn’t supported” he is, if he pauses for a moment to think, already in possession of the correct answer.

So, by that point in the comment thread it has clear to anyone who is reading that, yes, the Grauniad was correct – or, if you prefer the worst interpretation, that they were correctly reporting, in broad-brush terms, the numbers that are generally bandied about. That doesn’t stop the commentators still pushing “Someone needs to sue the paper for misrepresentation” and so on. Just a little later Steve from Rockwood asks “In discussing ice volume, how do they reliably estimate volume from the satellite data?” No-one there has any answer (which is odd, considering that they like to think they have a clue), but anyway, if SfR was actually interested he would have followed one of the links already provided.

And eventually, all doubt is removed: Phil Clarke finds the actual source from Greenpeace which the Grauniad has used, and yes indeed it is talking about volume, and the source is PIOMASS. AW gets really snotty in reply to that; pointing out the actual referenced source of the numbers in question has become, in AW’s words, “wasting my and everyone else’s valuable time with your diversions”.

The Slingo question

As noted, AW is heavily reliant on Slingo as his authority that ice volume has not declined by 75% (incidentally, I too wouldn’t assert that it has declined by X, and nor would the PIOMASS people, with certainty, I’d guess). But as a best-guess estimate its not implausible. The source for the JS quote is The Grauniad but the original is UNCORRECTED TRANSCRIPT OF ORAL EVIDENCE ENVIRONMENTAL AUDIT COMMITTEE PROTECTING THE ARCTIC WEDNESDAY 14 MARCH 2012 who are clearly very shouty people. The Graun’s quote from her is odd. They have her say:

* “We know there is something [happening on the thinning of sea ice] but it’s not as dramatic as those numbers suggest.”

instead of what she actually said:

* We know there is some thinning but it is not as dramatic as those numbers would suggest.

I can’t see why they prefer their longer and less clear and non-direct-quote version. But on: what question was JS actually answering with those words?

Q118 Chair: One lot of evidence that we had suggested that the volume of ice had already declined by 75%, and that further decreases may cause an immediate collapse of ice cover. Would you recognise that? Would you give credence to that?

Professor Slingo: No, I wouldn’t. We don’t know what the thickness of ice is across the whole Arctic with any confidence. We know that the sea ice extent has declined annually by 4% per decade, and in summer, yes that the sea ice is declining at a faster rate of 12% per decade. You also have to understand that it recovers pretty well as we go back into winter, so the 4% per decade annually is still there. We know there is some thinning but it is not as dramatic as those numbers would suggest.

So, this is ambiguous. She may just be reacting to the “further decreases may cause an immediate collapse of ice cover”. Although in answer to Q117 she has just said “We run quite a sophisticated sea ice model that includes the volume of ice, and it is fair to say, yes, there is a decline in the volume of ice” which I find surprising. If she is on top of a UKMO programme that parallels PIOMASS, why isn’t she quoting any numbers from it? That would be the natural thing to do. I’m not aware of UKMO/ Hadley “observational modelling” of sea ice like PIOMASS; they have HadISST, but that is area/extent type stuff. My suspicion is that JS has confused the climate-type GCM sea ice model with what PIOMASS are doing. Though if anyone has any better ideas, I’ll be interested to hear them.

JS isn’t a sea-ice modeller; I wouldn’t give any particular credence to what she says, at least insofar as it could be considered an interpretation of the PIOMAS 75% figure.


Finally, Scott notices the other anomaly, that “If they were talking about volume, then last year was the LOWEST, not second lowest. Thus, if they’re talking about modeled volume (at the summer minimum), then the second sentence is wrong”. This is (at last) a fair point (and one that AW is happy to sieze upon, since his existing “rebuttal” of its-not-volume is so unconvincing). The answer I can think of is that by the standards of newspaper journalism, swapping from volume in one sentence to extent in the next is hardly a big leap, indeed such a tiny one that they wouldn’t even notice it.

It is estimated that the North Pole could be ice-free in the summer within the next 10-20 years

I suppose we’re left with that. What does it mean? Hard to know. If you meant, literally, just the North Pole then maybe its plausible. If “North Pole” is a proxy for the whole sea ice cover, then I’m dubious. But you know that already.


In this case, if you strip out the mood-music from the peanut gallery and look only at the comments where people have made at least a small attempt to think, the crowd doesn’t do too badly, considering that they have all been put off the true scent by the trail AW has tried to lead. Dave, a True believer, even gently criticises WUWT for not writing a very good response to the Grauniad. Mat L argues

C’mon Anthony, you lose credibility when you start comparing sea ice extent with a volume metric and saying they don’t match. Fair enough if you missed this when writing the article, but now it has been pointed out to you, it’s disingenuous not to update your post/ graph.

[Update: I’m banned at WUWT. I’ve had some fun tweaking AW’s source for this nonsense, though -see the comments there. Back at WUWT, PaulB is doing a good bulldog on AW. I am curious to see how long before he gets stomped on – W]


* Nick Stokes has a nice set of plots of the PIOMAS data by year, etc., and with his nice “anomaly with trend removed”.

24 thoughts on “The Guardian’s ridiculous claim of 75% Arctic sea ice loss in 30 years – patently false?”

  1. We know you are dubious, but for “it is estimated … could be” the G can certainly point to a number of experts in the field who would back up that number, so their reporting looks OK to me.


  2. Oh, there has been more fun at WUWT and Tony:

    Tony gets involved in contradictions in the comments, but sticks stubbornly to his false claims. Funny.

    [I couldn’t bear to look at too much of that.

    I think AW long ago ran out of anything real to say, but has a readership, hence needs a constant stream of “stuff” to write. But its all comic-book stuff. Fortunately for him, that seems to be what his readers want -W]


  3. > supports it with number from thinkprogress

    There’s the problem right there.
    If you were to see a house on fire,
    would you throw Joe Romm on it?

    The Internet _really_ needs a proper Reference Desk.
    Professional librarians.

    Too bad they won’t work for tips.


  4. Er, perhaps I’m missing something, but … who cares?

    Who cares what Tony and his troupe think or write or foam on about?

    Sure, his stuff is entertaining and good for a giggle, but, seriously, a serious engagement with anything over there isn’t really possible. Mat L is either new, naive, or a serious fan if he thinks AW will change anything.

    Next, please.

    [Well, you have a point. And I certainly have no intent of ripping up all of his nonsense. But I’m interested in sea ice -W]


  5. Well, it’s interesting, Tony (he hates Eli calling him Tony) is thrashing like crazy. Basically the monster is eating him alive because it needs to be fed several times a day, and with the help of Nick Stokes and some others, some of the denizens are developing a clue. It is interesting.


  6. Oh yes, Eli tried to point out that Hansen’s buried paper has over 500 citations, but what the hey.

    [But, isn’t it sweet the way AW “outs” you every time you comment? He clearly doesn’t have much of a sense of humour -W]


  7. >”It is estimated that the North Pole could be ice-free in the summer within the next 10-20 years I suppose we’re left with that. What does it mean?”

    Nearest 1km^2 could have occasionally happened in the past, so I think that rules that out.

    Could be 100 km^2 or 1000 km^2 or …
    or how about could *sail* (i.e without use of engine or icebreaker) to pole and back?
    or maybe sail straight from Svalbard to pole to Bering Strait?

    It wouldn’t greatly surpise me if it was possible to sail to pole and back this September. What little multi-year ice is in the way is quite likely to have moved away.

    and the ice is clearly weak:


  8. * “We know there is something [happening on the thinning of sea ice] but it’s not as dramatic as those numbers suggest.”

    instead of what she actually said:

    * We know there is some thinning but it is not as dramatic as those numbers would suggest.

    Maybe it’s just me but I can easily see that “something” sounds like “some thinning” and the [ … ] was inserted to explain what the “something” was, i.e., this was mishearing what was actually said, rather than misquoting a part of the transcript for no apparent reason.

    [The “sounds like” argument only works if the Grauniad saw an earlier version of the transcript, which has since been corrected. That is possible, I guess -W]


  9. Ah, the nefarious editorial insertion ambiguity strikes again. [You’ve gotten Rommed]

    Square brackets are (aside for a few aberrant stylebooks) used for an editorial insertion meant to clarify.

    So where you saw
    >> They have her say:
    >> “We know there is something
    >> [happening on the thinning of sea ice]
    >> but it’s not as dramatic as those numbers suggest.”

    That began as a mishearing leading to mistranscription:

    [We know there is something but it’s not as dramatic …]

    Then the editors thought, well, that’s odd, right you are, we better clarify it, and made their square-bracketed insert.

    Then Someone Who Knows Better
    told or showed you
    What She Actually Said,
    which is, as you have it:

    >> We know there is some thinning
    >> but it is not as dramatic ….

    Here’s the principle to keep in mind:
    1) audio transcripts are typed by the cheapest available interpreter; this used to be non-English-speaking phonetically correct typists in small island nations, and by now may be done by playing the audio file over the telephone to a Google Phone answering machine that transcribes it for you.

    2) Clarification [what the editors thought she meant] (might be placed parenthetically) is often supplied by third or fourth hand parties who weren’t there, didn’t understand the subject, and didn’t ask the speaker what she said.

    [Yeeessss… but (see previous) the transcript appears to be OK -W]


  10. Maybe it’s from the reporter’s own notes, and they didn’t check the transcript. If you say that’s unlikely, I won’t disagree.

    You could just ask the reporter – if you cared enough, that is, and I can see that you probably don’t. If the change was made by a sub, they’ll as likely be happy to get the correct version out.

    [The difference between bloggers and real reporters is that we never go and talk to real human beings. In this case, the original is the HoC transcript. I think it is unlikely that the Grauniad had their own reporter taking notes, though it is possible. We may never know… -W]


  11. W,

    I think that Hank and I were suggesting something very plausible. Can you suggest another, more plausible explanation for the Grauniad’s apparent misquotation? I can certainly suggest other, less plausible ones. 😉

    (But anyway, the meaning is not altered, is it? This is light-years away from what some elements of the press do when reporting science.)


  12. 2,230 hits for the quoted string including the square brackets.

    My guess is it’s from someone’s oral report, typed what he heard, phoned a story in, something like that.


  13. It was a piece by one of the Guardians more ‘lifestylesy’ types so the language used lacked clarity.

    There was the usual influx of interesting one post characters on that thread. Any time a Guardian story with open comments appears on the wacky ones web page the average IQ on thread takes a dip.



    “A panel headlined “Cold hard facts about the Arctic” (Magazine) said: “Of the Arctic sea ice, 75% has been lost over the past 30 years. Last year saw sea ice levels plummet to the second-lowest since records began.” We should clarify that this figure, supplied by Greenpeace, comes from research into sea ice volume and not the more commonly discussed “sea ice extent” or area. The figure was taken from a University of Washington Polar Science Centre’s assessment based on computer modelling – the Panarctic Ice Ocean Modelling and Assimilation System.”


  15. > sea ice volume and not the more commonly
    > discussed “sea ice extent” or area

    Ask the Titanic survivors which is more important …


  16. Hmm, interesting days for sea ice right now, with a record rapid decline leading into the period of highest insolation.

    So William, why no SEARCH contribution? I mean, even Petr Chylek has an oar in…

    [IJIS is interesting indeed, still let us not examine every wiggle. As to SEARCH: I have nothing to say other than “trend” -W]


  17. AGW deniers mantra shown again in Watt’s article :

    If there is any way in which any AGW evidence CAN be misinterpreted, it WILL be misinterpreted by WUWT.


  18. The ice melt can’t have increased any. Because S.F. Singer said in his book written about 2004 the ice melt won’t increase. So It just can’t have can it? The esteemed Fred wouldn’t possibly be wrong.


  19. Given the change in ice extent it is possible to make a first approximation of the decrease in ice volume. Think of the area of ice as a square. Take the square root of how much it has decreased (or increased). Lets say the area this year is 80% (0.8) of some previous year. The square root of 0.8 is .8944. That is to say, the length and the width must have decreased to 89% of the former year to give an 80% decrease in area. Now make the assumption that the thickness has decreased by the same amount. Cube the above figure and you get .7155. That is to say, if the area (extent) has decreased to 80% of some former year, it is likely that the volume is 71.6% of the former volume. If the sept 15 area is 30% of the historic extent, the volume is 16% of the historical volume.


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