Vast Ice ‘Island’ Breaks Free of Greenland Glacier

From NYT, a quote of researcher Jason Box:

Petermann [glacier] is a sleeping giant that is slowly awakening. Removing flow resistance leads to flow acceleration… The coincidence of this area loss and a 30 square kilometer loss in 2008 with abnormal warmth this year, the setting of increasing sea surface temperatures and sea ice decline are all part of a climate warming pattern.

Here’s the graphic from the article:

How big is this “ice island”? From Montreal Gazette:

The biggest Arctic “ice island” to form in nearly 50 years — a 250-square-kilometre behemoth described as four times the size of Manhattan — has been discovered after a Canadian scientist scanning satellite images of northwest Greenland spotted a giant break in the famed Petermann Glacier.


62 thoughts on “Vast Ice ‘Island’ Breaks Free of Greenland Glacier

  1. GregL

    Ice shelves at the mouths of glaciers retard glacier flows. Most of the action in Greenland glaciers had been on the Atlantic side; obviously that is now changing.

  2. CoRev

    Menzie, and in the 19th century there was an Antarctic glacial iceberg that took days to sail around which lasted for several years. So what’s your point? Glacier’s calve?
    Or do you think that glaciers are supposed to continuously grow in size? Oh, they do, that’s why we call those periods glacial, and the interims inter-glacials. Which is better for us?
    So, I ask again, what’s your point in putting up these contrived articles? Isn’t this just an example of asymmetric weighting of evidence? (Psst, you brought it up.)

  3. c thomson

    Hooray! With this one, we can all find our inner Krugman! Whee!
    Bring on the Wailing Wall! Let’s hold hands and snivel!
    I blame George Bush.

  4. W.C. Varones

    I love being lectured about global warming by people who eat meat. These busybodies want to pass laws to tell everybody else how to run their lives but they won’t even make small changes in their own lives like giving up meat:
    In a 2006 report, the U.N. Food and Agriculture Organization (FAO) concluded that worldwide livestock farming generates 18% of the planet’s greenhouse gas emissions by comparison, all the world’s cars, trains, planes and boats account for a combined 13% of greenhouse gas emissions.
    How about when Al Gore gives up his private jets and CO2-spewing mansions, and lesser global warmists stop eating meat, we’ll start taking them more seriously.

  5. Menzie Chinn

    CoRev: One word for you: frequency.

    c thomson: Point of information: Are you implying that people “snivel” at the Wailing Wall? Please clarify.

  6. CoRev

    Menzie said: “CoRev: One word for you: frequency.” Others are persistent and passionate. :-))
    Menzie this comment lifted from WUWT explains a lot about why the CAGW (C=Catastrophic) skeptic movement is growing. It can be found here:
    “This WUWT post is the key to the skeptical scientist and the reason Anthony has put together a huge surfacestations quality effort. Ross and Steve have just published a paper which shows that the trends in models are outside of the satellite temperature measurements by 2 to 4 times. I think its one of the most important results in climate science that Ive seen this year.
    If you combine Ross, Steve, Chads work at the link with even a slightly reduced trend from UHI (surfacestations project), models need to be recomputed to match observations. More importantly, because the warming weve measured is less than predicted, the conclusions need to be revised.”
    Predictions based upon estimates that are proving to be 2-4 times too high???? CO2??? Causes some heating, but how much? Answer and prove that question, then we can go forward.

  7. c thomson

    Professor Chinn: Two words for you: Size and Frequency.
    ‘Wailing Wall’ is a metaphor. Run it by a grad student in the English dept.
    Please keep it up, though. There is too little public humor these days. We don’t want to be reduced to John Kerry and Sarah Palin, do we?
    As a thread, how about the tragic departure of Professor Doctor Mrs. Romer? One duff forecast and back in the cage she went. You could kick off with ‘all forecasting is dangerous, especially the future.’ Discuss.
    As always, I blame George Bush.

  8. Menzie Chinn

    c thomson: I think the conjoining of “sniveling” and “Wailing Wall” speaks for itself, sub-text-wise.

    CoRev: Er, what exact degree does the WUWT blogger have in the area of climatology? (And I’m not speaking of meterology).

  9. 2slugbaits

    c thomson My understanding was that Romer had long ago stated that she would be leaving when her son entered high school this fall. And it’s something of an open secret that she was particularly eager to leave the CEA and get back to the Bay area because she expects Obama to nominate her to the SF Fed job that opened up with Janet Yellin’s promotion.

  10. CoRev

    Menzie, your appeal to authority is unappealing in the extreme. Climatology by its nature requires expertise across several sciences. If you knew anything about the article or actually went to the site (I prefer Jeff Id’s article), ( ) you would understand the issue.
    The issue is Santer in his 08 paper stopped comparing the models with data ending in 1999. The authors of the article in question are renowned, in climatology for debunking many of the dendro-climatology findings, just used Santer’s methods carrying the data to present.
    Novel idea isn’t it.
    So why do you think Santer stopped at 1999 in a paper published in 2008?
    It must have been Bush’s fault! :-))

  11. 2slugbaits

    What degrees do McIntyre or McKitrick have in climatology? None. McKitrick is an economist who has written nothing of any substance in the field of economics. And McIntyre is a blogger who worked as an industry consultant in mineralology. They have on occassions made some useful contributions to the debate, but their main purpose today is to provide a kind of petina of intellectual respectability to those who want to deny manmade global warming without appearing to be neanderthals. In many ways they play the same role as the Discovery Institute in the evolution versus intelligent design arguments. M&M have long been convinced that the reason professional journals don’t publish their work is because of some kind of deep inside cabal. They have something of a martyr’s complex. This endless whining about data quality problems is the kind of thing that WUWT blog readers, whom I suspect don’t actually have jobs in which they work with realword data, might find convincing.

  12. CoRev

    2slugs, said: “M&M have long been convinced that the reason professional journals don’t publish their work is because of some kind of deep inside cabal. They have something of a martyr’s complex.”
    Try this explanation: “Steve McIntyre said
    August 8, 2010 at 12:19 am
    Nick Stokes, in a different paper submitted to IJC as a COMment on Santer et al available on, we did an exact replication of Santers method, AR1 and all, on updated data and got results that contradicted Santers. This paper was rejected twice. Rest assured that Santers results do not hold up with updated data.
    In one of the Climategate emails, Santer coauthor Peter Thorne, who appears to have been one of our reviewers, snickered to Jones about the rejection of our submission.”
    So who’s more likely to have the true story, M&M or a snarky 2slugs?
    BTW, 2slugs this article has nothing to do with data quality, but is all about comparing the model outputs and current observed temps.

  13. CoRev

    For Menzie and 2slugs re: why some skeptics find it difficult to get published. Here’s Ross McKitrick’s history of the current paper under review.
    I have written quite a bit on this, including a book, journal articles, think-tank reports and media op-eds. In general Im trying to get out of the area, but as the saying goes, touch the devil and you cant let go.
    Global Warming CO2 Emission Trends
    I am interested in the question of what future global CO2 emissions will be and how the IPCC forecasts them. I think the IPCC has exaggerated likely future emission trends. This conclusion is based on empirical work (coauthored with Mark Strazicich and Junsoo Lee) which is undergoing the long, slow journal review process. The Fraser Forum article and the Post op-ed give the gist of the argument, but the article under review goes into a whole lot of econometric detail and provides a theoretical growth model to explain why the empirical results make sense, and why settling the related issue of convergence will be important for constraining future emission forecasts.
    Spring 2010: The paper continues to bump along. We spent 18 months going through 3 rounds at one top journal, but there was one (of 3) referees who just hated the paper and would not allow it to be published, despite the fact that we rebutted all his or her objections. Then we went through 3 rounds with another journal, and in the process of dealing with the new referee comments we’ve expanded the paper quite a bit. (Next they’ll tell us it’s too long.) We added a 3rd author, Junsoo Lee, who helped us with the Bayesian forecasting section. The last round took 15 months to get referee replies, and the editor ended up adding a new referee who insisted on rejecting the paper based on the claim that our results couldn’t be replicated. We got the referee’s code and found the error in it, but the editor wouldn’t reopen the matter, so it’s now under review somewhere else.”
    For anyone interested this was from his site here:

  14. Menzie Chinn

    CoRev: Every one of us has a publication horror story like this. It is only news to outsiders to the economics profession. And yet, most of us manage to publish (and do not whine about it on our blogsites). I cannot say that this story alters one iota my view about McKitrick’s research.

    By the way, I am not appealing to authority. I am appealing to expertise. As someone with a PhD, I know what training is involved, and hence on average lend more credence to someone with an advanced degree. In point of fact, we do not even know if Mr. Watts has a degree in meteorology. Since he is unwilling to be forthcoming in any fora I am aware of (which seems unattractive in somebody arguing for transparency), count me skeptical.

  15. CoRev

    Menzie said: “By the way, I am not appealing to authority. I am appealing to expertise.” C’mon now Menzie, pull my other finger!
    Are you playing 2slugs now? Misdirection re: Watts who has no relationship to the article i have been referencing.
    As to Watts’ degrees, who cares? He was not an author on the article in question. He is an expert in siting of the US surface stations. Until he started his surface station review program, no others had done it. Regardless, it has no bearing on this article.

  16. tj

    A new paper showing change in CO2 does not drive global warming.
    Except for the Yamal reconstruction, all tree-ring and non-tree ring reconstructions appear to agree, and so indicate no correlation between temperature and atmospheric CO2 concentration.
    Just keep ignoring the data and let big government advocates and the popular press make your decisions for you.

  17. Menzie Chinn

    CoRev: Sorry, I see the article you mention now. I was confused, as you have repeatedly noted WUWT website approvingly (am I mistaken on this count? I can go back through the comments to cross-check, but haven’t had a chance). I’ll take a look at the article you mention. I was trying to figure out how many peer reviewed articles Dr. McKitrick has — quite difficult! Ah, well, for now, my day job calls.

  18. CoRev

    Menzie, what’s the problem with citing WUWT? You seem to be denigrating it. Why? It’s easily as reputable as RealClimate, run by the Team of climatologists at NASA/GISS. Furthermore, WUWT has many guest articles, more so than many of the pro-AGW sites. But then most important factor is it’s, by far, the most popular science blog. It was number 1 in 2008.
    Another point, Ross McKitrick, Steve McIntyre, Lucia, and many others have gained reputations at being fair in their writings. Science is about letting the data take you where it will. What Climategate has shown is that the AGW leadership do not practice science, but advocacy politics, or at best group-think dominated science.
    If you do not believe this, then I can only conclude you have not read the emails.

  19. 2slugbaits

    CoRev I read McK’s paper (link below). Can you tell me what it is about that paper that you find convincing?
    First, aside from the merits of the paper, it isn’t the kind of thing that one would ordinarily find in a peer reviewed journal, so McK shouldn’t get his hopes too high. The paper does not make any new theoretical advances, it is just a case of applied econometrics using existing software. At most universities that would be part of a Masters program.
    Second, he doesn’t really explain why he takes monthly data and imposes an AR(6) model. I’ve given guest lectures on time series analysis to grad students and faculty at UAH as well as my fellow government pukes who work at Redstone Arsenal and an AR(6) model isn’t one that jumps out at me as likely.
    Third, he used panel models (random effects or fixed effects???) but I didn’t see where he reported the intercept term. Maybe I missed it, but in most panel models the researcher is usually at least as interested in differences in the intercept as differences in the slopes.
    Fourth, why no investigation of seasonality?
    Fifth, he says that they used a linear model because they didn’t see any evidence for nonlinearity. Really? And yet in some of their models they used an ARIMA (2,0,0) w/o constant formulation? Hmmm…doesn’t that suggest a trend-in-trend?
    Finally, look at Figure 1. Notice the bold line that is supposed to be a Hodrick-Prescott filter to smooth trends. Now look at the fine print. See the lambda value? It’s 200. He used a lambda value of 200 for monthly data. Why?

  20. 2slugbaits

    CoRev: So would McKitrick be able to answer why you found the paper convincing? I would have thought that you would have been the best source for that. Afterall, you’re the one who recommended it, so I’m assuming that there was something in it that grabbed your attention. It’s a very short paper, so there’s not a lot of explanation.

  21. stunney

    Meanwhile, Russia is burning up.
    Let the free market solve the problem.
    1. Privatize air.
    2. Provide large tax breaks for air producers.
    3. Sell off national parks.
    4. Outsource forestry services.
    5. Abolish fire safety regulations.
    6. Cut taxes on burn treatment clinics.
    7. Blonde TV airheads wearing gas masks are sexy.
    8. It’s still cold at the South Pole.
    9. The Russians deserve it because they were Commies.
    10. Glenn Beck is on later.

  22. CoRev

    2slugs, since when did my opinions matter. BTW, nope, not gonna play. Go over to Jeff Id’s or WUWT and play with the big dogs and get embarrassed again.

  23. Menzie Chinn

    CoRev: I had only a brief glance at the paper on panel estimation. I must confess I had this intense feeling of time travel. The authors assume stationarity of detrended series, but assuming trend stationarity in raw series!!! I think very few time series econometricians would entertain such assumptions these days. (There’s not even a pre-test for the data, series by series or in a panel context — and these tests are built into standard statistical packages these days).

    The authors assertion that they did not see any evidence of nonlinearity (didn’t see tests here, in any case) is not a good defense. The issue is difference stationarity, not nonlinearity.

    Overall, one of the most bizarre papers I’ve read of late, econometrics-wise. But good for a chuckle.

  24. 2slugbaits

    CoRev: My mistake. I typed ARIMA (2,0,0) but meant to type ARIMA (2,2,0). But I see that I misinterpreted his chart and the second “2″ refers to something else despite the rather odd way of displaying the data. In any event, it raises an interesting question is to why you might build a model with 6 AR lags and not go for a more parsimonious representation using differences.

  25. mike

    For what it’s worth, 2slugbaits, your responses are not likely to convince anyone of your position, except the choir. Thanks to the Climategate e-mails, flaunting credentials and lofty appeals to authority are no longer decisive stratagems in discussions of AGW. Likewise, using “razzle-dazzle” technical language no longer has its “I’m smart/you’re dumb” intimidating effect. If you want any sort of credibility, I recommend you spell out your critique in terms that an intelligent, interested layman can follow.
    For your consideration 2slugbaits: WUWT and similar sites offer plausible, seemingly cogent critiques of AGW theories. For the most part, “experts” like you do not expose yourself to the rough-and-tumble of AGW critic blogs. If you think you’ve reduced McKitrick’s paper to a “chuckle” then let him have it with both barrels in his own blog. To a certain extent, CoRev and others like him (like me) use “little guy” logic when asessing AGW issues. Namely, if one side in the AGW debates is “playing games”, then that’s a pretty good sign there’s a problem with their position. You’ll forgive me, 2slugsbait, but you’ve been playing games in your responses.

  26. CoRev

    Menzie, my same advice to you as 2slugs. They don’t bite and welcome meaningful comments. We all would like to advance the science.

  27. CoRev

    Menzie, I just read the current set of comments over at Jeff Id’s and note neither you nor 2slugs have commented.
    I chuckle at the hair splitting going on here, while ignoring the big picture. The models diverge from real world temp observations/calculations after 1999!
    These are the current last two comments that I feel summarize the discussion.
    Phillip Bratby said
    August 9, 2010 at 2:21 am
    I find this thread fascinating and illuminating. Nick Stokes as devils advocate has teased out further information from the authors and has led to greater understanding and greater confidence in the results of MMH2010. This is an example of real peer review in action. It has been carried out with great civility and none of the ad hominems and insults so prevalent at RC.
    This kind of review and questioning can never be carried out at RC, where insults and moderation stop any sensible ongoing discussion and understanding.
    Jeff Id said
    August 9, 2010 at 5:52 am
    I love this quote:
    But with the addition of another decade of data the results change, such that the differences between models and observations now exceed the 99% critical value. (My bold)
    Its not a close call.”
    I left High School nearly 50 YA, and this conversation feels like the sniping made by some youngsters sitting on the sidelines who missed the cut to make the team. Go over and advance the science.

  28. RicardoZ

    Is Greenland actually returning to being green? Could it be that Greenland will actually return to supporting farms and crops production? Could the Vikings once again find Northe America?

  29. GregL

    We don’t have the pertenant info needed to evaluate this article:
    Is the caving front of Petermann glacier retreating over time? The story doesn’t tell us and neither has any commentary on the story.

  30. colonelmoore

    Bringing our attention to this issue is wasted effort. Every bit of mineable coal and drillable oil will be used by developing countries. If EPA regulates coal power emissions, the coal will go to China and India and other emerging economies. All the pumpable oil will be used by emerging economies. A realist understands that they have no intention to ever regulate emissions.
    So what is the proponents’ realistic fallback position? If there were a way to regulate atmospheric CO2 concentrations in real time at the sink rather than the source, and if we could call it “green,” one would think that this would be popular. Everyone knows what I am talking about so I won’t repeat it.
    But the goal is not to find a solution but to place blame, in the vain hope that voters will “come to their senses” and make this a winning campaign issue for Democrats. Only when this becomes toxic to Democrats’ election prospects, like gun control, will the push to revamp our energy structure finally end. Then people might finally look for ideas that can actually be implemented.

  31. JJ

    This is an economics blog. I clicked out of curiosity to see how Prof. Chinn had managed to relate this to economics. What does this have to do with economics? Is Prof. Chinn turning this into politicsbrowser or oddlyenoughnewsbrowser?

  32. Menzie Chinn

    JJ: I regret that my choice of topics does not hew to your expectations. I further regret that you had to expend two extra clicks of the mouse in order to satisfy your curiosity. However, I would have thought the economic implications of global climate change, of which this event is indicative of, would have been obvious:

    The US Economic Impacts of Climate Change and the Costs of Inaction

    An Overview of Potential Economic Costs to
    Washington of a Business-As-Usual Approach to
    Climate Change
    (the State where I grew up).

    CBO, Potential
    Impacts of Climate Change in the United States

    “Climate change set to boost Mexican immigration to the US, says study,” Christian Science Monitor.

    “Climate Change Seen as Threat to U.S. Security,” NYT.

    I hope this set of links will have in some small way illuminated why I thought this topic was of some economic interest.

  33. Kurt Tietjen

    This is always an interesting thread. Some people think that having people with money give some of their money to people without money is somehow going to retrend global temperatures down. Guess what, the earth is cooling and has been cooling for a billion years. Humans will eventually die out, so let’s sit back and enjoy the ride and not get all over each others cases because it’s a waste of time and if anyone actually DOES anything on this subject, it’ll be a complete waste of money. These weather people can’t tell me if it’s going to rain tomorrow and i’m going to listen to them tell me that the ocean levels are going to increase by 80 feet or some nonsese?

  34. 2slugbaits

    Mike: Earlier in this thread I made that comment that blogs like WUWT serve the same purpose for AGW skeptics that the Discovery Institute serves for believers in intelligent design; it provides a petina of intellectual respectability for those who have already decided that they want to deny global warming, but are looking for some kind of support. You see the same thing with Heritage and the Hoover Institute. The reason I asked CoRev why he found the paper convincing was obviously intended to point out in an indirect way that CoRev really didn’t understand McK’s paper, but he liked the conclusion and as far as he is concerned that’s good enough. We see the same thing with a lot of econ talk on both sides of the aisle, but especially on the far right. You hear GOP pundits and politicians claim that the possibility of higher tax rates are what’s causing business to sit on cash; but what you don’t hear is any coherent and plausible economic model that actually explains why the certainty of higher tax tomorrow should cause businesses to sit on their hands today. If anything standard economic models tell us that businesses should be hiring like mad if they believe corporate taxes will be higher tomorrow. Another example is the Ersatz economics idea of tax cuts paying for themselves. This is nonsense and people who advocate it should be embarrassed into having to explain it or else concede they’re wrong. If all you can do is parrot WSJ editorials or WUWT blog claims without actually understanding the nuts and bolts of the argument, then you’re not an informed skeptic…just someone who is being cynically manipulated by those with an economic interest in advancing some claim.
    CoRev: As I recall the folks over at Air Vent just used AR(1) models all of the time even though (as they aknowledged) the AR coefficients were always > 0.9 and usually close to 1.00. My complaint was that they should have been either testing for unit roots or at a minimum using some kind of Box-Jenkins approach to frame an ARIMA model. Their answer basically came down to saying that they had always used AR(1) models and really weren’t convinced of the need to look further. And this gets to Menzie’s point about the difference between difference stationary series (i.e., those that have to be made stationary through differencing) and trend stationary (i.e., those time series that have a deterministic time trend). This is an old argument in economics going back to the Nelson-Plosser stuff on macro variables. In fact, if memory serves Menzie actually co-authored a paper on GNP being trend vs difference stationary. But I digress. The point is that if you’re going to do econometrics on temperature data, then you need to follow standard procedures. But as I also said, I believe that this whole business about trying to apply econometric time series analysis to climate data is pretty much a waste of time. A misbegotten enterprise if ever there was one.

  35. CoRev

    2slugs said: “But I digress. The point is that if you’re going to do econometrics on temperature data, then you need to follow standard procedures. But as I also said, I believe that this whole business about trying to apply econometric time series analysis to climate data is pretty much a waste of time. A misbegotten enterprise if ever there was one.” and that was after he said: “Their answer basically came down to saying that they had always used AR(1) models and really weren’t convinced of the need to look further.”
    So in one paragraph he says one use of standard procedures instead of more advanced/powerful approach is not good enough, BUT, when an advanced more powerful approach is used without the standard practices as used in a different field is … what? Bad usage? Not standard, Ah, yup that’s the more appropriate term.
    2slugs and Menzie, I realize the bad position you are in. If you support the McK/McI et al approach in the paper you support their findings. If you dispute their approach, without a follow up comparison, it requires a level of effort, but more importantly you run the risk of just proving again (as I suspect will happen) the approach used in the paper. Finally, if you do the work and disprove the findings, there is still no guarantee your results will support the Santer findings. Too many opportunities to embarrass the AGW community, and in no way could a true believer support a finding that disproved the models! Quite a conundrum!
    Without the models there is no CAGW. Without CAGW there is no opportunity to save the world from … (fill in your latest potential catastrophe here.) Remember it’s all man’s fault.

  36. Mike

    Thank you 2slugsbait (may I call you 2slugs?)for your response. Your reply both clarified your position and showed a civility that is sometimes missing from AGW discussions.
    Likewise, I’d like to clarify my point of view (for what it’s worth), as well. At the outset, let me acknowledge that AGW “skeptics” undoubtedly include in their ranks useful fools, agents of influence, tools, dolts, true believers, “parrots”, and hustlers with hidden agendas out to make a buck. But such characters also infect the ranks of AGW advocates. There is big money riding on both “Big Green” and “Big Carbon.”
    Let me add, we live in a world of “experts” that assure us that housing prices always go up; that lending fabulous sums in home loans to people who can’t pay the money back is smart, sophisticated business (new paradigm in risk management, dontcha know); that various Ponzi schemes are good investments because they are run by individuals of unquestionable reputation, close to regulators and prominent politicians; that the threat of swine-flu requires the diversion of big-bucks to well-connected pharmaceutical firms; that Saddam Hussein has WMD; and the like. You get the picture.
    I would also like to emphasize my “little guy” credentials. I have only a limited time, intellect, and background with which to pursue the AGW issue. However, I do have a citizenship responsibility to make the best possible estimate of AGW matters, especially as they pertain to the reasonableness of AGW claims, pro and con, and vote and advocate accordingly.
    Fortunately, mankind has at its disposal an awesomely powerful tool with which to make reasonable determinations of the “truth” in AGW matters and any other matter, as well. Indeed, that potent tool makes it possible for even individuals like myself, with my profound limitations, to reach reasonable conclusions in areas, like AGW, that involve technically complex issues, beyond my personal competence.
    The tool–the dialectic. A rigorous, open, adversarial debate of one’s propositions. Such debates allow competing advocates to make their best case and allows us “little guys”, like juries in a complex court case, to get a pretty good angle on who knows what they are talking about and who is slinging the proverbial B. S.
    Hence my recommendation that you take on McKitrick. You’re obviously a smart guy, 2slugs, I’d love to see you in the ring with McKitrick. You’re too good, in other words, to limit yourself to well-flashed credentials, appeals to authority, avian references to those with whom you disagree and Manichean schemes of taxonomy for those with one or another position on AGW.
    Of course, the dialectic is poison to hidden agendas, hustles, and power plays. Hence its unpopularity among some in preference for PC thought, taboo subjects, and advocacy using techniques akin to those of a clever, laundry soap sales campaign. Again, that’s not you, 2slugs. Suit up and come out fighting–please.

  37. CoRev

    Moving on: The Mckitrick et al paper has been accepted by Atmospheric Science Letters. Now the scientific process can continue.
    Yes, 2slugs & Menzie, you can team to write your own paper to improve or disprove the McK econometrics approach. Science as it should be played instead of the sidelines chuckling we have seen.

  38. Menzie Chinn

    CoRev: If I am asked to referee such a paper in the future, I will. That’s how the process works. Otherwise, I’ll let any competent econometrician working in the area deal with it. For now, I’ll use the McKitrick-McIntyre-Herman paper as an example for my students of how not to do panel time series analysis.

  39. tj

    That’s a great idea. I am sure the results of your assignment will also include alternate approaches and I hope you will share the results with us. Are you teaching econometrics this term?

  40. Menzie Chinn

    tj: Thanks for the support. No, don’t get to teach a lecture econometrics course this coming year, but who knows for the future. Here is my undergrad course in economic statistics at UW; my master’s level course website at UCSC is no longer online, but here’s the syllabus.

    I ws referring to instruction one-on-one. For instance, you can see a list of my Ph.D. students on my links page. That is primarily what I meant by talking about teaching students how not to do panel time series analysis.

    Regarding the proper treatment of difference stationary series, which is germane to discussion of the McKitrick paper, see this post.

  41. Menzie Chinn

    tj: Well, then, it they are “at the cusp”, he could’a run a KPSS test. That, too, is built into standard statistical packages. This approach of using tests with different null hypotheses is implemented by Cheung and Chinn (Oxford Economic Papers, 1996; J. Bus. & Econ. Stat., 1997).

  42. Robert

    One of the telling indicators for me as an interested observer to the AGW discourse is the tone of the discourse on, for example, RealClimate compared to WUWT or climateaudit. As I surveyed the on-line landscape a few years ago, the pro AGW sites seemed to be smug, condescending, and somewhat circular.
    The fundamental problem for me with the argument continues to be the lack of explanation for the cause of the medieval warm period (MWP) and slightly earlier warm periods (demonstrated by retreating glaciers that uncover human artifacts). Go back to the first IPCC report and look at its graph of the MWP.
    Lacking an explanation, paleo-climatology disappeared the MWP. Very Orwellian.

  43. CoRev

    Menzie, you have carped a lot on the margins of the Mck/Mci approach, but have not mentioned the results/conclusions of their “peer reviewed” report. From the CV stand point he appears to be your equal, similar backgrounds, training, and an expanded interest in AGW. He has taken his AGW interest a little further than you have.
    2slugs made the point that they did not advance the science. (Note: he, reasonably, did not pursue that path.) If you check the history of their paper, it was first presented using the Santer08 approach AND DATA, while extending the data from 1999 to present.
    After being stonewalled at International Journal of Climatology, they rewrote the paper and used a new econometric approach, thereby advancing the science with new methodology and new findings. It was eventually accepted at Atmospheric Science Letters. Both versions of their paper showed the same results.
    if you have an issue with the approach, data, findings then get in touch with either at McI’s ClimateAudit:
    They are both reasonable folks, and take constructive criticism well. Advance the science!

  44. Sam Simple

    The human race is finished. It’s only a question of time. These fools that think global warming is some sort of political, us vs. them, Dems vs. Repubs, etc. are stupid and immature. I hope they live to see the oceans boil, which they will.
    The choice really comes down to: do you want the human race to be extinct in 50-100 years (Vote Republican) or extinct in 100-200 years (Vote Democrat). It’s gonna happen folks, and soon! Enjoy your lives while you can!!!

  45. 2slugbaits

    Robert: The graph in the first IPCC report was an unfortunate mistake. It never should have been included. Now that was an example of bad scholarship. The chart was something that was just sort of found amidst some dusty books and it took quite an effort to eventually track down the source. It was largely notional and didn’t have a lot of support outside of monastery records in Europe. But including that chart was a mistake which was corrected with subsequent IPCC reports. The evidence for a MWP is mixed at best. Fair amount of proxy evidence for warming in Europe, Japan and North America, but pretty strong evidence of significant cooling in central Asia.
    CoRev: The issue of trend versus difference stationarity is really the crux of my argument with the folks at Air Vent. That’s why I was stunned to read about AR(1) coefficients usually greater than 0.96 and absolutely no testing at all. Zilch. Look, I challenge you to find any econometrics textbook published in the last 25 years that doesn’t concentrate on unit root tests. In fact, a few years ago I recall reading where unit root tests were the single biggest topic in Econometrica. And right behind unit root tests were papers on cointegration, which is basically nonstationary unit roots applied to more than one variable. As Menzie said, every decent statistical package today includes unit root tests. In my everyday work I use EViews, SAS, LIMDEP, GRETL and JMULTI and every last one of them has a smorgasbord of of tests.
    I did not say that M&M did not advance the science of global warming. What I said was that they did not make any theoretical advances in terms of methodology. I said that the paper was an example of applied econometrics, which is typically a Masters level of work and isn’t the kind of thing that gets you published in an econometrics journal. There’s nothing wrong with applied econometrics…we all do it, but if you’re going to do it then you at least ought to conform to standard methods and practices.
    As to advancing the science, M&M did have a valid critique of Mann’s inappropriate calibration technique in his Hockey Stick chart. Mann used a principal components model that summarized many highly correlated variables into a few “principal” variables. That’s kind of standard stuff. The problem was that when he calibrated the model with actual instrumental data he used a nonstationary period. M&M correctly caught the error. So that was kudos for M&M. But M&M also made their own blunders in 2003 and 2005. In their paper they gauged their model on interannual forecast error and then tried to apply that model to project interdecadal change. That creates bias…in fact, that bias is far greater than anything that was in Mann’s original paper. If you take M&M’s calibration correction and then correct for M&M’s bias, what you end up with is something that is with 0.1 degrees of what Mann originally said. Basically the warming in the 15th century that M&M found just completely disappears.

  46. Menzie Chinn

    CoRev: Advancing the science in the correct way takes time, a very scarce commodity. And I’m sure there are people in the discipline of climatology who know these (basic, basic, basic) time series methods. I’ll let them deal with it. I have enough difficulty convincing people to deal with nonstationary time series in macro/public finance to occupy my time (and there my impact will be bigger, because I have written in the area).

    By the way, if you want to compare cv’s, and the impact of individual papers, I suggest you take a more quantitative approach. A standard is to use the Web of Knowledge database (the database formerly know as the “Social Sciences Citation Index”). Alternatively, Google Scholar can do something similar, but counting unpublished works. While neither of these approaches are anywhere near perfect, I suspect they are superior to your ocular tabulation.

  47. Jim Satterfield

    Skeptics are not interested in advancing the science. If they were you wouldn’t find them clinging to lies and dis-proven arguments. Like you still claiming that “Climategate” still proves how the conspiracy on the part of climatologists means the likes of M&M don’t get published as opposed to them just not doing good science. Like continued claims that M&M disproved the “hockey stick” or that the Mann studies were the only ones showing similar trends.
    This entire post of yours shows your prejudice and complete lack of understanding of anything not colored by your love of the denialists, and yes, the inhabitants of WUTW are denialists, not people who just don’t agree on the cause of warming. The entire point of the failed surface stations project was to try and prove that warming wasn’t real but an artifact of the methods of measurement.

    Menzie, what’s the problem with citing WUWT? You seem to be denigrating it. Why? It’s easily as reputable as RealClimate, run by the Team of climatologists at NASA/GISS. Furthermore, WUWT has many guest articles, more so than many of the pro-AGW sites. But then most important factor is it’s, by far, the most popular science blog. It was number 1 in 2008.

    Another point, Ross McKitrick, Steve McIntyre, Lucia, and many others have gained reputations at being fair in their writings. Science is about letting the data take you where it will. What Climategate has shown is that the AGW leadership do not practice science, but advocacy politics, or at best group-think dominated science.

    If you do not believe this, then I can only conclude you have not read the emails.

    You are incapable of understanding that the CRU scientists and their correspondents have been found by several investigations to be innocent of the accusations you and your fellow deniers of the science have leveled. But it’s all part of the grand conspiracy, isn’t it?
    BTW, referring to expertise is not the same thing as appeal to authority and WUTW is not a reputable site except among people like yourself. Watts has no education in the field. And his great project just hasn’t produced the results he was hoping for.

  48. mike

    Professor Chinn:
    If it is not too much trouble, could you please advise why you suspect that your recommended “quantitative” approaches to CV comparisons are “superior” to CoRev’s “ocular tabulations?” At a minimum, please list the known imperfections, that you acknowledge but do not reveal, with both his and your recommended techniques of CV comparison. Also, since we’re dealing with your mere suspicions that your approaches are superior to CoRev’s, could you please help us to understand and appreciate the cogency of your suspicious nature?

  49. Menzie Chinn

    mike: I would’ve thought this would be obvious, but here goes. Glancing at publications in a set of journals as an outsider to the professional literature would probably not yield much information to the examiner, since peer reviewed journal A would look much like peer reviewed journal B. As an insider, one has much more information as to quality of the journal. But quality is somewhat subjective. So, a useful adjunct is to use the quantitative information that the information technology revolution has made available.

    One such thing is raw count of citations. SSCI/WoK does that – but since it tabulates citations in publications, theres a lag issue. There is a long lag between time a paper is circulated, then is cited, then the citation in a published article is tabulated (publication lags from *acceptance* to publication can be as long as two years). That particular lag problem is mitigated by Google Scholar. But that counts everything that’s on web — published and unpublished, peer reviewed and not peer reviewed.

    In both instances, controversial papers would probably receive an upward bias, for obvious reasons.

    Note, the information technologies revolution also means that we have systematic means of assessing the impact of publications, and thereby ranking researchers by their impact. IDEAS has such a ranking.

    I hope this clarifies matters for you.

  50. mike

    Professor Chinn:
    That was a great response, thanks. Indeed, your reply has encouraged a certain boldness, on my part. You’ve previously declined to provide a detailed critique of McKitrick’s paper. But could I urge a reconsideration? After all, you’ve already done the research and have even worked up your critique for presentation to your grad students. How much time and trouble could it be to slip all the fine work, you’ve already done, into a paper, I wonder. Also, it would be valuable to have Mckitrick’s rejoinder to your critique, which will not be forthcoming unless you produce your critique more formally and publically. I anticipate a spirited exchange between yourself and McKitrick that can’t help but be enlightening. CoRev is right, even obviously right, that’s the best way to advance the science and to advance the public policy debate, as well.

  51. CoRev

    JimS, you are kidding. Right? Mann’s Hockey Stick still has merit in your mind? OMG!!!!!
    BTW, we are still waiting for the Watts et al, Surface station article to be printed in a journal. If it is rejected too many times we know where it will be released, the most visited GW site, not WUTW.
    Menzie, I see you have a belief in “quantity has a quality all it’s own.” It’s too early to determine the impacts of the latest McK paper, but from its current impact it might just be significant. If it survives the true review process, sunlight of replication, then its actual impact will be determined. Santer08 appears to be less than shelf ware at this point.

  52. CoRev

    Menzie & 2slugs, Here’s a recent comment from RMcK:
    Ross McKitrick
    Posted Aug 10, 2010 at 11:09 PM | Permalink | Reply
    I have just arrived at our cottage after a day-long flight/boat ride from home, and I am on a slow dial-up for the next 3 weeks. I am just looking at this thread for the first time. I dont want anyone thinking that if our IJC comment had gone through, the ASL paper would not have been written, i.e. it was only a tool for getting the tropical troposphere material out in another form. That is not the case. I have had it in mind to challenge the 1930′s era trend comparison methods used in climatology for a long time, and this topic was a good one to use as an application. The exasperating reviews at IJC kept us from printing a simple demonstration of the effect of updating the data while staying with Santers method, but Id have written about the need for better methods in any case.
    Over at James Annans blog a few insta-experts are obviously very relieved to have convinced themselves that they dont actually have to read our paper or deal with the results, because in their view the methodologies are all so obviously wrong. I dont plan to use up my dial-up time trying to figure out the basis for their jubilation, or trying to figure out how they avoid arguing along the way that models are simply immune from any empirical test. But I look forward to hearing about the impending submissions to econometrics journals by these would-be tutors explaining why panel regression methods yield biased standard errors, and why the multivariate convergence results in the Vogelsang-Franses paper are invalid.
    However, before anyone sets to writing up such papers, I would suggest they reflect on some basic statistical modeling concepts, such as what it means to estimate a model under the null hypothesis rather than under the alternative. Sorry if that seems cryptic, but where I work thats a pons asinorum.

    From here:
    Wiki definition of pons asinorum: “Whatever its origin, the term pons asinorum is used as a metaphor for a problem or challenge which will separate the sure of mind from the simple, the fleet thinker from the slow, the determined from the dallier; to represent a critical test of ability or understanding”
    In that comment he also made this point” I dont want anyone thinking that if our IJC comment had gone through, the ASL paper would not have been written, i.e. it was only a tool for getting the tropical troposphere material out in another form. That is not the case. I have had it in mind to challenge the 1930′s era trend comparison methods used in climatology for a long time, and this topic was a good one to use as an application. The exasperating reviews at IJC kept us from printing a simple demonstration of the effect of updating the data while staying with Santers method, but Id have written about the need for better methods in any case.
    Bolding just for 2slugs.

  53. tj

    Take a look at this chart of Hansen’s model predictions vs actual temps and tell me if you need a stationarity test to see that the model is wrong.
    Note that of the 3 models, the only one that comes close to reality is the one that assumes a counterfactual – “a drastic reduction in GHG emissions is assumed for 1990-2000.”
    Given the divergence between predicted and actual values for the period 2000 – 2010, I conclude any similarity for the period 1990 – 2000 is coincidental.
    The model is clearly much too repsonsive to changes in GHG’s, casting doubt on the ‘consensus’ that man is responsible for the bulk of global warming over the last 20 years.
    Let’s reduce air/water pollution, the rate of deforestation, etc, but let’s do it in a sensible manner. The imposition of an enormous carbon tax on U.S. taxpayers and businesses will not reduce global warming and will not address the multitude other sources of pollution and man-caused environmental damage.

  54. tj

    Who wants to try and debunk this paper?
    McShane and Wyner 2010, (Northwestern and Penn) submitted into the Annals of Applied Statistics (forthcoming).
    It destroys Mann’s hockey stick. As many of the ‘deniers’ here have said all along – the climate is warming but it is not unprecedented and it is not warming at an alarming rate.
    All that remains to completely debunk the Catostrophic AGW theory is to watch as the earth cools over the next decades, (as predicted by a variety of models that do not rely solely on AGW).

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