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Comments 54501 to 54550:

  1. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    sout #71 says: I don't know why you are going on and on about the conspiracy side of things. The first article annoncing this survey in the mainstream media was Adam Corner’s in the Guardian with the headline: “Are climate sceptics more likely to be conspiracy theorists?” More recently, Britain’s most popular serious paper, the Telegraph, covered the story in an article with the headline: “Climate change deniers 'are either extreme free marketeers or conspiracy theorists’”. Lewandowsky’s paper is headlined: “NASA faked the moon landing - Therefore (Climate) Science is a Hoax”. The survey is all about linking scepticism of climate science to belief in conspiracy theories.
  2. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    @catamon #21 Indirectly you raise a couple of interesting points. 1) Studying the time lapse images of the yearly Arctic ice melt it becomes clear that in all likelihood the last of the ice during the summer minimum will end up against the north Greenland coast -- perhaps because it's fed by the calving glaciers(?). And following on from that... 2) The next big summer melt landmark will be the moment that the North Pole becomes part of the area that is 'ice-free'. At that point (as others have pointed out) Father Christmas is homeless. This will be an important news item to prepare for.
  3. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    There is an abstract at AGW Observer today on the Arctic sea water temperatures. Deep Arctic Ocean warming during the last glacial cycle - Cronin et al. (2012) It starts out - Abstract: “In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice loss. ...." If I'm reading it right, it's saying their research indicates there is a layer of warmer water, below cold fresh surface water, that gets pushed down during a glacial period and rises during warming. After reading the SkSc article, I wondered if this might have something to do with climate models under estimating sea ice loss. ?
  4. Models are unreliable
    Sphaerica, Whatever we use to illustrate and communicate our science must, in my opinion, be valid and justified. Otherwise we are simply gilding the lily. The fact that life and death decisions can be made with a paucity of information does not mean that we would be better off not doing so if we can. My opinion is simply that if we are using models to predict outcomes and inform our decisions then if we are confident in them and can demonstrate that to others: (1) we will more easily gain acceptance of the need for and impacts of our decisions, and (2) our decisions are more likely to be good ones. If the models can be so easily discarded, then we have spent a very long time and a lot of money & effort that could have been better employed elsewhere. If, however, they are a key element in improving our understanding and ability to communicate the problem then we can't afford to discount the need for them to be robust and demonstrably so. My point, which I'm still not sure was either wrong or silly, was simply that since we are using these tools I was interested in seeing how they were performing because that is how I increase my confidence in other peoples knowledge and build my own. Your point (1) in 'the bottom line' indicates to me that you think exactly the same way: a model of physics predicted the change and the observations supported those predictions - and you use this evidence to support your knowledge.
  5. Realistically What Might the Future Climate Look Like?
    John Russell @55 Farm machinery doesn't have to be fossil fuel powered. But, yes, leaving out machinery, it would be more efficient to grow on a small scale. That's great, if you live where you can grow everything you want, or are willing to settle for what you can grow. I guess I could live without coffee and mangoes. Transport will still be needed, however. I don't think all the people in Arizona or the sub-Sahara can grow their own food locally, at least not without importing a lot of water.
  6. Models are unreliable
    563, opd68, Sorry, I've been too busy to follow the conversation and get caught up on everything that's been said, but this one comment struck me (and it's wrong):
    Once we start using that model to predict future impacts and advise policy then we must expect to be asked to demonstrate the predictive capability of that model, especially when the predicted impacts are so significant.
    We're not entirely using models to predict and advise. It's one tool of many, and really, if we wanted to we could throw them out (at least, the complex GCMs, I mean -- after all, all human knowledge is in the form of models, so we can't really throw that out). The bottom line is: 1) The physics predicts the change, and predicted the change before it occurred, and observations support those predictions 2) Multiple, disparate lines of investigation (observations, paleoclimate, models, etc.) point to a climate sensitivity of between 2 C and 4.5 C for a doubling of CO2. 3) None of this requires models -- yes, they add to the strength of the assessment in #2, but you could drop them and you'd still have the same answer. The models are an immensely valuable tool, but there is no reason to apply the exceptional caveat that they must be proven accurate to use them as a policy tool. Poppycock. Human decisions, life-and-death decisions, are made with far, far less knowledge (conduct of wars, economies, advances in technology, etc.). To say that we need even more certainty when dealing with what may turn out to be the most dangerous threat faced by man in the past 50,000 years is... silly.
  7. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    21, catamon, WTF moment? Don't bet on it. There will be: 1) Joy that we can finally drill and easily traverse the Arctic. 2) Certainty that this has all happened before, and it's part of a natural cycle. 3) Questions of how you can possibly think that the loss of Arctic ice is caused the the thoroughly discredited GHG Theory to begin with.
  8. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    17, Albatross, Personally, I don't think that distinction is going to matter for more than a few years. People can fight in that period over the distinction, but after that zero ice will be the new black. Then the game will switch to "how early" in the year zero is reached. And we get to see the answer to the really big question, which is "will there even be winter ice once the summer ice is seriously gone?"
  9. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Figure 2 in this is a pretty striking one. As far as "ice free" Arctic summer goes, i think the big media hit will come when we see something like figure 2 with just a small patch of ice, completely surrounded by open water at the pole. Has to be a WTF moment for "skeptics" when that happens surely??
  10. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Albatross said: "Either Christy is ignorant of where the body scientific evidence and theory stands and that his opinions are by far associated a fringe element, or he accepts that and is guilty of engaging in highly misleading rhetoric and propaganda in public..." ____ There is another possibility. Christy is blinded by his own belief structure that tells him that Anthropogenic warming simply can't have such drastic effects as melting the Arctic decades before most climate models even said it would happen. In this case, Christy is guilty of the "confirmation bias" problem in that he only sees what he wants to see and interprets it based on his paradigm that AGW is small at best and will not have significant impacts...
  11. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    This is an excellent article, and provides a comprehensive overview of the state of the Arctic from a long-term perspective. Takeaways from this: 1) Arctic is headed toward an ice-free condition in the next few years(possibly by 2020). 2) Human activity is the cause. 3) The deniers of #1 and #2 will stop at nothing to hold on to their illusion for as long as possible, and when the inevitable ice-free Arctic arrives, they'll say something like "so who cares...it doesn't affect me." or worse, "now we can get at the oil." For a nice summary of this summer's Arctic melt, take a look at this article, with links to other research that answers the question, "Why you should care...": [LINK]
    Moderator Response: [RH] Hot linked url
  12. Miriam O'Brien (Sou) at 12:57 PM on 5 September 2012
    AGU Fall Meeting sessions on social media, misinformation and uncertainty
    @geoffchambers - the study found that extreme right wing ideology was a strong predictor of rejection of climate science. The number of conspiracy theorists who responded was very low (unsurprisingly). Conspiracy theorists were separated from 'skeptics' in the analysis and the attempt to analyse them found not as high a correlation with science rejection as with 'skeptics' in any case. So I don't know why you are going on and on about the conspiracy side of things. As for 'skeptics' not seeing the survey. A 'skeptic' such as you've described would be bound to visit a broad range of websites and not huddle on 'skeptic' websites. Therefore the chances are that some of them would have seen and responded to the survey. As comments on mainstream climate science websites (such as this one) illustrate, even 'fake skeptics' visit here and elsewhere. This is borne out by the survey responses. The study findings should not be surprising to anyone, whether they are a fake skeptic or someone who seriously wants to know facts. The reaction baffles me. As anyone who visits climate science blogs and anti-science blogs knows, many 'skeptics' claim climate science is a left wing hoax. Yet there seem to be a lot of 'skeptics' who want to dispute the finding of this survey, that having a more conservative bias, particularly at the extreme end, is a predictor of rejection of science. The reaction of 'skeptics' seems to me to be contrariness taken to absurd lengths.
  13. Models are unreliable
    JasonB - clearest response/conversation I have had on that ever. Thank you. scaddenp - what I am looking for is each 'against' argument dealt with rationally and thoughtfully, which is why I'm working through this as I am.
  14. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Getting back to the focus of the OP, some pretty good responses to misinformation can often be found on the same "skeptic" site that publishes the misinformation, down in the comments. It is true that it can be buried in noise, that comes with the audience. The social media acceptance of dissonance, contradiction and noise is a hallmark of this debate, popularity does not often come with quiet rational discussion, but popularity has its advantages.
  15. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Sorry... links fixed here, please feel free to delete the first one. Alert to false balance, I was pleasantly surprised by a Sydney Morning Herald article by journalist Nicole Hashem. She found a way to avoid false balance while still providing an alternative view in this article about Tim Flannery and a Climate Commission public forum. You'll need to read the article to see who she used for balance, I won't spoil the moment. Sydney Morning Herald I liked it so much, I blogged it here.
  16. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    John @7, That is a very important and valid question. Fortunately, people have been thinking about this. Right now, IIRC, the accepted definition of an Arctic free of sea ice is when the sea ice extent drops below 1 million km^2. But it would be very prudent at this point to unequivocally define what is meant by "ice free". Does it refer to ice extent, area or volume, or all three metrics dropping below specified limits? Does it refer to those limits being met for a day, 5 days or a month? Which product (or products) will be used?
  17. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Jason B @15, Good catch. We noticed that too. One has to really question whether or not Christy truly believes what he is saying. Regardless of how one tries to frame it, it reflects very poorly on him. Either Christy is ignorant of where the body scientific evidence and theory stands and that his opinions are by far associated a fringe element, or he accepts that and is guilty of engaging in highly misleading rhetoric and propaganda in public. Sadly, it would not be the first time that he has engaged in the latter.
  18. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Composer and skywatcher, Ironically, the self-styled "skeptics" seem to not understand what it means (or involves) to be a true skeptic. What we have here, on this very thread, are examples of the behaviour of what is more accurately called fake skeptics. Perusing the thread quickly exposes the fake skeptics. To the fake skeptics I say, please stop abusing and soiling the term "skeptic" by associating it with your misguided and ideological belief system. Stephan has enough material following this fiasco to write a paper on a case study of fake skeptics confirming the very hypothesis that they are railing against. Too funny for words.
  19. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    I like the way Christy used the phrase "To some... To the rest of us...", implying that those he disagrees with are actually the ones in the minority. It reminds me of the following exchange in Blackadder: Rum: Opinion is divided on the subject. Edmund: Oh, really? [starting to get the picture] Rum: Yahs. All the other captains say it is; I say it isn't. The response seems apropos, too: Edmund: Oh, God; Mad as a brush.
  20. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    I would have to say that the modern sceptic/skeptic movement is not as passive as the ancient Greek version. I am here thinking of the skeptics that organize JREF, or who form the blogging collective Skeptic North, or similar outfits. Rather than simply deferring judgement on phenomena or claims until all the facts are in, the modern skeptic behaves in a manner similar to the professional scientist: accepting caims proportionately to the evidence that can be mustered to support them. At any rate, whatever definition one uses, skywatcher's point that self-styled skeptics of climate science are, in their uncritical acceptance of dubious contrary claims in the face of an enormous body of consilient supporting evidence, definitely not behaving in a manner consistent with skepticism, stands.
  21. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    A reply to #64:
    A sceptic is someone who suspends judgement until he knows all the facts.
    I haven't seen much evidence of that at many 'sceptic' websites about climate science. Instead, there's copious evidence of people uncritically accepting any old rubbish so long as it appears to contradict the consilience of evidence on climate change. One week there'll be an argument saying CO2 rise is natural, the next week CO2 won't be rising; the week afterwards, CO2 is rising but it's not warming; after that, it is warming but it's all natural; after that it's UHI; after that, the scientists are making everything up; but after that CO2 won't be scattering IR radiation and warming the surface (somehow); after that, the hockey stick is broken (except when it shows a large MCA, in which case palaeoclimate evidence is perfect); after that, it's all the Sun, which is odd if it's not warming! And of course it's always cooling, because 'sceptics' don't seem to be able to understand the difference between signal and noise! There's precious little real scepticism being shown by so-called "climate sceptics". So many of these arguments are either contradicted by the full body of evidence, or contradict themselves (e.g. "it's not warming" and "warming is natural"). There's no coherent hypothesis to explain the existing evidence. Not one "sceptic" has come up with such an hypothesis, despite years of this so-called debate. "Scepticism" would be a great deal more believable, and less like a conspiracy theory if climate sceptics could come up with a coherent hypothesis to test. But I'm not holding my breath. The real 'sceptics' are scientists, who test their hypotheses to breaking point all the time, and have thus come up with the theory that CO2 is the biggest control knob on climate, one we're turning right now, a theory that fits the physics, the observations, the palaeoclimatic evidence and the models. Please come up with a better theory! I want the science to be wrong on this. But I need strong evidence to do this, not a hodge-podge of mutually contradictory and easily falsifiable ideas with precious little evidence to support them.
    Moderator Response: [DB] Fixed text.
  22. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    GeoffChambers @54 and foxgoose @65, if there is a problem with announcing preliminary results, it is at most that it might bias the returns from "skeptical" sites should it be heard of. This is only a problem if the survey did not have a deadline for completion prior to Sept 23rd, 2010. Should Lewandowski have received a large number of responses after announcing the preliminary results that changed the outcome, he would merely have to have corrected the announced result.
  23. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Clarifications Apparently my comments have caused a stir in the blogosphere, and require some clarification. First, apparently some people are treating my comments as representing an official view of Skeptical Science. They are not. I have only spoken for myself; and will never speak as an official spokes person of Skeptical Science except in my limited role as a moderator. Nothing I say or write outside of moderation boxes on SkS represents any view other than my own, although other SkS authors may agree with me to a greater or lesser extent. Second, I have not called for the retraction of the Lewandowsky paper. My understanding is that the paper is accepted for publication, but not yet printed. As such it can be withdrawn from publication to allow time for a re-write to correct what I consider to be major flaws. If, however, it has already been printed, it should not be retracted. Retraction is an admission of fraud, or of completely unscientific practice, neither of which have occurred here. If the paper has already been printed, the appropriate course, should Lewandowsky become convinced of the existence of major flaws, is the printing of a correction. It has been suggested in private correspondence that calling for the withdrawal of a paper is a major insult. It was certainly not my intention to insult Lewandowsky and his co-authors; and I regret any offense that they have taken. It has further been suggested that calling for withdrawal is equivalent to saying, "Your work is of such shameful quality that it needs to be removed at once." In my view this is an absurd interpretation. In my view it is equivalent to saying, "Your work as it currently stands is likely to mislead, and as I accept that you are a person of principle, I expect that you do not want to do that, even inadvertently, and will act accordingly". My full response on this point, minus an introductory and identifying comment, was:
    "Unless it is acceptable practise for scientists to knowningly allow falsehood to be published under their name, on hearing of a significant flaw in their paper, the paper must be re-written if there is time; withdrawn and re-written if there is not time for a rewrite before going to press; or have a correction published if it has gone to press. Because these are minimal standards of proper conduct, suggesting that an as yet unprinted paper be re-written or withdrawn is no more offensive than suggesting that it contains major flaws. The only way my suggestions can be considered offensive is if it is insulting to suggest major flaws in somebodies paper. Such an ettiquette is, however, entirely inconsistent with the vigourous review that is the sin qua non of science. Such an ettiquette may have grown up among scientists by custom; but in that event it is irrational and I will not pander to it."
    Third, lest there be any doubt, there is no reasonable suggestion of fraud or other scientific wrong doing here. At most Lewandowsky has been too casual in screening for gamed responses; and slightly over interpreted the results. That represents a major flaw in the paper (if I am correct); but has no implications whatever about Lewandowsky's integrity as a scientist. IMO, Lewandowsky's choice of a title is, and should be, far more damaging to his reputation as a scientist than the other flaws (IMO) in his paper.
  24. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    chriskoz @5 - all of our posts on Christy are included in the blog posts tab of his 'skeptic' page.
  25. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    As kevin s @11 notes, the criticism is of false balance. When 97% of experts agree on something, getting a quote from one of the few who disagree is not achieving balance, it is creating the semblance that there is serious dispute amongst the experts, over-representing the few 'skeptics'. As the post above clearly shows, there is really no dispute in the scientific literature that the current sea ice decline is unprecedented over the past several thousand years and primarily human-caused. Christy's inclusion in the article didn't add anything except unnecessarily sowing doubt where no serious doubt exists.
  26. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    sout #63: “There are differing views among experts on whether to force a response (eg have a four point scale) without a neutral mid-point or whether to allow neutral and/or don't know responses”. Agreed. But this was a survey designed to attract sceptics, and be used by sceptics. A sceptic is someone who suspends judgement until he knows all the facts. This definition goes back at least as far as Pyrrho of Elis in the 4th century BC and maybe further (Anyone got their Diogenes Laertes handy?) Lewandowsky, in an interview on a University of Western Australia site, makes much of the fact that he received responses from Australia; the USA; the UK and elsewhere. (That’s how we have to piece together the demographics of this survey, because nothing is revealed in the paper itself). I, an Englishman, know nothing about the Oklahoma bombing. How much does the average American know about the death of Princess Diana, or the average Australian about the US policy on interning extraterrestrials? We sceptics are likely to be doubtful and unwilling to commit ourselves. So we get chucked out of the survey for refusing to answer, in other words, for beng ... sceptical.
  27. Models are unreliable
    opd68 - you are correct that obviously sensitivity is ultimately a function of the model construction. "our input assumptions" of course are known physics. You ask "are we confident in our understanding of the forcings that are underpinning our predictions at increasing CO2 levels?". The answer is yes, but I wonder what you are looking for that could give you that assurance? It's rather exhaustively dealt with in Ch9 from memory of the AR4 IPCC report. If that didnt convince you then what are you looking for? These forcings and response can be verified independent of GCMs.
  28. New research from last week 35/2012
    The Nature Climate Change September issue contains Anderson and Bows "A new paradigm for climate change". The blurb on the issue homepage says: How climate change science is conducted, communicated and translated into policy must be radically transformed if 'dangerous' climate change is to be averted. The paper is behind a paywall, but is discussed in the available editorial "Clarion Call".
  29. Miriam O'Brien (Sou) at 04:34 AM on 5 September 2012
    AGU Fall Meeting sessions on social media, misinformation and uncertainty
    First, the absence of a neutral (I don't know/I know nothing about it) option... A neutral response is not the same as a 'don't know' response. The former is the mid-point on the (Likert) scale (eg option 3 of 5 options or option 2 of 3 options). The 'don't know' option is basically the same as not offering a response and is separate from the choice scale itself. There are differing views among experts on whether to force a response (eg have a four point scale) without a neutral mid-point or whether to allow neutral and/or don't know responses. And some people use different scales and choices in some circumstances but not others. I expect Dr Lewandowski has a reasonable amount of experience in surveys and would certainly have access to literature on the topic.
  30. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Thanks for the article. Clyde: Interesting comment. If you---or anyone for that matter---has evidence that the recent decline in Arctic sea ice is "similar" to other time frames, I'd actually be quite interested in reading about that. However, I'm not interested in reading the other assertions in your comment. The article above clearly lies out why Christy's claims are questionable at best. Believe it or not, there are many people from this "point of view" who would actually be thrilled to wake up one day and find that the concern regarding greenhouse gases and climate change are entirely unfounded. However, the world around us is full of increasing evidence that convince me otherwise.
  31. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Clyde, the criticism about "balance" is precisely that the media does not present a truly balanced view. Perhaps a better way to say it is that the common approach in the media is not to present a properly weighted view. Please consider an analogy. Let's say you consult one hundred doctors about some symptoms you have. 97 of them give you diagnosis A, 2 do not arrive at a clear diagnosis, and one gives you diagnosis B. When loved ones ask after your health, would it be a properly balanced response to say "Well, it could be A or it could be B"? This is what is being criticized in the post above. The mainstream media presents the position of about 1% of scientists who have studied climate as though it is of comparable relevance to the position of about 98% of scientists who have studied climate. It is not balance, it is "balance;" an Orwellian term if ever one existed.
  32. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    (-Snip-)
    Moderator Response:

    [DB] Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive or off-topic posts. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.

    Finally, please understand that moderation policies are not open for discussion. If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it as no further warnings will be issued.

  33. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Tom Curtis writes:
    I was talking to my wife about the Lewandowsky paper yesterday. She noted two points in particular. First, the absence of a neutral (I don't know/I know nothing about it) option in the questions was a serious methodological flaw. This is particularly the case for the conspiracy theory questions, in which at least one of the conspiracy theories are obscure (IMO), and not inherently implausible:
    I can partially answer this question with the cited literature. Belief in Conspiracy Theories, Ted Goertzel, 1994 cited by 81
    The respondents were then asked their opinions about nine other conspiracies which had been in the news lately. A four point scale was used, ranging from "definitely true" and "probably true" to "probably false" and "definitely false." "Don't know" was not offered as an alternative, but was recorded when the respondents volunteered it. This question wording encouraged respndents to give their best guess as to the truth of a conspiracy, while relying the distinction between "probably" and "definitely" to distinguish between hunches and strong beliefs.
    Now let me be clear that it does not fully answer the question of how a respondent would be able to show that this conspiracy was an "unknown". Perhaps the answer lies in the ability of an online survey vs a phone survey (as was the case in Goertzel 94). But it's a good question for Stephan L to answer nonetheless.
  34. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    @metzomagic #59: Such alredy exists in Ostrichville which, by the way, is a gated-community.
  35. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    I can see Christopher Booker's Telegraph column right now. How do we head that off?
    I had an image in my mind of a representation of Santa's place, in place at the North Pole, and with 360° webcam monitoring. Imagine the restive response of the planet's kids as they watch the digs of their favourite fantasy character disappear. Imagine how the adults of the world might explain to their children why they're allowing Santa's shed to not-so-slowly sink into the sea.
  36. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    There is no such thing as a 'perfect' survey. Methodology always plays some part in determining the results. Self selecting internet surveys and small sample sizes layer several additional concerns on top of those standard problems. However, Lewandowsky seems to have acknowledged these issues in his results, stated that the results were limited to a specific sub-group of skeptics, discussed the uncertainties, et cetera. It is not a perfect survey because it cannot be. No such thing exists. That said, it seems adequate to its task. I'm surprised by the hub bub. When I first heard of these results my reaction was along the lines of, 'Yes... and the Earth revolves around the Sun and the sky is blue.' The findings of this survey fall into the category of 'blindingly obvious'. Of course there is a correlation between internet GW 'skepticism' and free-market ideology / belief in conspiracy theories. Half the stuff we see from these people is about how the evil scientist cabal is faking data and any sort of CO2 regulation would destroy the economy and usher in world communism. Go to any of the blogs complaining about the survey and I guarantee you will find plenty of examples proving it redundant.
  37. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    You can already see it coming: "Surveygate" :-)
  38. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Hmph! Is there an 'unthwarted' version of the NSIDC 'Observations and model runs'-graph somewhere? It's not that I question the data per se, but having it presented thus in 3D gives space for 'interpretation'. Is the red line in front of the blue field, is is lower because of the 'lifted' POV etc. Let's leave the graph-mangling to Monckton and his ilk.
  39. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    When, sometime in the not-too-distant future, the Arctic becomes -- to all intents and purposes -- 'ice-free', it will be important that it's worded correctly in newspapers, articles and blogs. I'm sure we can all imagine the rush amongst those in denial (and Daily Mail reporters) to find a photo of any ice still remaining, or reforming, anywhere within the Arctic circle -- at any time of year -- to prove, "it's all a hoax". I can see Christopher Booker's Telegraph column right now. How do we head that off?
  40. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    #55 Michael Sweet No, I don’t think it was a conspiracy, simply a poorly conceived survey, with much to criticise in the questionnaire, the methodology, the analysis and the conclusions. Following the statement from the moderator that I should contact John Cook directly, I received a cordial email from John Cook yesterday offering to answer my questions. I wrote back briefly, asking simply when he posted Lewandowsky’s request, when he deleted it, if there had been any comments, and whether they still existed or had been deleted too. That was just over 24 hours ago. I’ll post his response here when I receive it.
    Moderator Response:

    [DB] "I’ll post his response here when I receive it."

    Not unless it is explicitly made clear that the contents of the email are for public dissemination.

  41. Miriam O'Brien (Sou) at 20:08 PM on 4 September 2012
    AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Agree with BernardJ and Michael. I do a lot of internet surveys. Interim results can be virtually instant if you've set up your analytical software in advance. Had McIntyre posted a link when he got the first or second request and his visitors had responded, then given the numbers of responses recorded, the main difference would more than likely have been that N would have been higher.
  42. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    I'm with michael sweet on this point. Any competent researcher will have established a priori his statistical analysis methodology - in fact that's a fundamental assumption of any experimental protocol. His/her spreadsheets would have been constructed, populated with dummy data, run, examined, and refined until all s/he need do is to drop in the real data as it comes, with the results returned almost immediately after the last entry. All the more so if s/he's an old hand at the process. With progressive data entry, there should be no surprises by the end: only the establishing of the final few decimal places. geoffchambers is looking for reds under the bed.
  43. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Geoff, So Lewandowsky processed his data as he received it. When McIntyre turned him down he announced what he had collected. What do you think would be better, for Lewandowsky to sit on his data forever waiting for a response from the skeptics? Your entire premise is that there was a conspiracy to prove that skeptics believe in conspiracies. Your position proves that you believe in conspiracies. Your posts are in violation of the comments policy. You are wasting our time. Go cry somewhere else.
  44. Models are unreliable
    opd68,
    Are we confident in our understanding of the forcings that are underpinning our predictions at increasing CO2 levels?
    The forcing resulting from increasing CO2 levels is very accurately known from both physics and direct measurement. By itself it accounts for about 1.2 C per doubling. The forcing from water vapour in response to warming is also quite well known from both physics and direct measurement and, together with the CO2, amounts to about 2 C per doubling. Other feedbacks are less well known, but apart from clouds, almost all seem to be worryingly positive. As for clouds, they are basically unknown, but I think a very strong case can be made that the reason they are unknown is precisely because they're neither strongly positive nor negative. As such, any attempt to claim that they are strongly negative and will therefore counteract all the positive feedbacks seems like wishful thinking that's not supported by evidence. If anything, the most recent evidence seems to suggest slightly positive. One way to avoid all these complications is to simply use the paleoclimate record. That already includes all feedbacks because you're looking at the end result, not trying to work it out by adding together all the little pieces. Because the changes were so large, the uncertainty in the forcings is swamped by the signal. Because the timescales are long, there is enough time for equilibrium to be reached. The most compelling piece of evidence, for me, is the fact that the best way to explain the last half billion years of Earth's climate history is with a climate sensitivity of about 2.8 C, and if you deviate too much from that figure then nothing makes sense. (Richard Alley's AGU talk from 2009 covers this very well, if you haven't seen that video yet then I strongly recommend you do so.) Look at what the evidence tells us the Earth was like during earlier times with similar conditions to today. This is a little bit complicated because you have to go a really long way back to get anywhere near today's CO2 levels, but if you do that then you'll find that, if anything, our current predictions are very conservative. (Which we already suspected anyway -- compare the 2007 IPCC report's prediction on Arctic sea ice with what's actually happened, for example.) No matter which way you look at it, the answer keeps coming up the same. Various people have attempted to argue for low climate sensitivity, but in every case they have looked at just one piece of evidence (e.g. the instrumental record) and then made a fundamental mistake in using that evidence (e.g. ignoring the fact that the Earth has not yet reached equilibrium, so calculating climate sensitivity by comparing the current increase in CO2 with the current increase in temperature is like predicting the final temperature of a pot of water a few seconds after turning the stove on) and ignored all of the other completely independent lines of evidence that conflict with the result they obtained. If they think that clouds will exert a strong negative feedback to save us in the near future, for example, they need to explain why clouds didn't exert a strong negative feedback during the Paleocene-Eocene Thermal Maximum when global temperatures reached 6 C higher than today and the surface temperature of the Artic ocean was over 22 C. My view is that the default starting position should be that we assume the result will be the same as what the evidence suggests happened in the past. That's the "no models, no science, no understanding" position. If you want to move away from that position, and argue that things will be different this time, the only way to do so is with scientifically justifiable explanations for why it will be different. Some people seem to think the default position should be "things will be the same as the past thousand years" and insist on proof that things will change in unacceptable ways before agreeing to limit behaviour that basic physics and empirical evidence shows must cause things to change, while at the same time ignoring all the different lines of evidence that should be that proof. I find that hard to understand.
  45. Realistically What Might the Future Climate Look Like?
    @gws #52 The development of the abbreviation 'CAGW' -- which is used almost exclusively by the denial lobby -- is interesting. I think 'CAGW' started to appear when a significant section of the fake sceptics realised that -- in spite of years of denying that CO2 is a greenhouse gas, that the planet is warming and that humans are causing it (and so many other memes) -- they would finally have to start secretly accepting the mounting evidence supporting the idea of AGW. At that point they had to rethink their denial and thus start to re-cast the 'debate' (as they saw it) into one of whether the outcome of climate change would be serious. Opposing 'CAGW' lets them continue denying and keeps their real agenda -- that we should do nothing about the problem. Of course, as we all know, just because those who switch to using 'CAGW' when commenting on posts -- thus demonstrating their underlying acceptance of 'AGW' -- will never go as far as to correct the more ill-informed fake sceptics who are still denying the unquestionable basics of climate science. They're just happy that doubt is being sown.
  46. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    sout #53 McIntyre says he received the request from Lewandowsky’s assistant 6th September, (a week after the survey had been posted at Tamino, Deltoid etc) and a follow up request two weeks later. That brings us to 20th September. 23rd of September Lewandowsky gave a presentation at Monash University in which he anounced the results of the survey, with the current sample size of 1100 (i.e. after the elimination of false data and duplicated IPs). So three days after asking for cooperation in fieldwork, he’d processed the results and written his conclusions and announced them.
  47. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    I'm afraid my caveats on figure 2 didn't make it into the final article. Figure 2 is a comparison of the end of August for 2012 to an unspecified August estimate for the 1938 data. It would be better to use the NSIDC August average, or the extent from a date in mid August. Unfortunately NSIDC doesn't seem to archive its daily images, and the August average is not available yet. I will provide an updated figure as soon as I can. Also, the white area in the 1938 image in not observed directly: The observations are the red lines and symbols (and possibly coastal observations which are unmarked), so some of it is speculative. However everywhere where observations are available, the limits of the ice extend far beyond this years pack. Nonetheless, the best evidence we have found directly contradicts Chisty's claims. If he has any evidence to support those claims, he should present it.
  48. Models are unreliable
    JasonB - all clear and understood, and I agree completely that the same clarity and scientific justification is required for the opposite hypothesis of increased CO2 having no significant effect on our climate. Science is the same whichever side you are on. I spend my working life having people try to discredit my models and science in court cases, and doing the same to theirs. I therefore think very clearly on what is and what is not scientifically justifiable and am careful to state only that which I know can be demonstrated. If it can't I am only able to describe the science and processes behind my prediction/statements which by necessity become less certain the more I am asked to comment on conditions outside those that have been observed at some stage. My entry to this conversation is because I keep hearing that the science is settled and I want to see that science. From what I have learned here (thankyou!) the key question for me (which I will start looking through at the climate sensitivity post) is: - Are we confident in our understanding of the forcings that are underpinning our predictions at increasing CO2 levels?
  49. Record Arctic Sea Ice Melt to Levels Unseen in Millennia
    Thanks Dana for nice summary on recent ice, especially the pointers to those arctic/greenland reconstructions that were unknown to me tonow. Fig3 & 4 nicely represent Arctic amplification: delta T=3K within 64-90°N vs. 0.8K globally. I would suggest to add the recent John Christy's testimony in Congress to Christy Crocks button. That latest crock deserves a big prominence, because it's beyond my comprehenssion how a person of his stature could sacrifice his entire reputation by telling evident lies under oath. And he keeps doing it while evidence keeps mounting with 2012 melt.
  50. Models are unreliable
    opd68, The Intermediate form of this post contains six figures (including Tamino's) demonstrating the results of exactly the kinds of tests you are talking about. The first one, Figure 1, even shows what should have happened in the absense of human influence. Since the models aren't "tuned" to the actual historical temperature record, the fact that they can "predict" the 20th century temperature record using only natural and anthropogenic forcings seems to be exactly the kind of demonstration of predictive capability that you are looking for. The objection usually raised with regards to that is that we don't know for certain exactly what the aerosol emissions were during that time, and so there is some scope for "tuning" in that regard. But I think it's important to understand that the aerosols, while not certain, are still constrained by reality (so they can't be arbitrarily adjusted until the output "looks good", the modellers have to take as input the range of plausible values produced by other researchers) and there are limits to how much tuning they really allow to the output anyway due to the laws of physics. I think that if anyone really wants to argue that there is nothing to worry about, they need to come up with a model that is based on the known laws of physics, that can take as input the range of plausible forcings during the 20th century, that can predict the temperature trend of the 20th century using those inputs at least as skillfully as the existing models, and has a much lower climate sensitivity than the existing models do and therefore shows the 21st century will not have a problem under BAU. Simply saying that the existing models, which have passed all those tests, aren't "good enough" to justify action is ignoring the fact that they are the most skillful models we have and there are no models of comparable skill that give meaningfully different results. Due to the consequences of late action, those who argue there is nothing to worry about should be making sure that their predictions are absolutely, scientifically justifiable if they expect acceptance of their predictions, rather than just saying they "aren't convinced ". In the absence of competing, equally-skillful models, how can they not be? Regarding climate sensitivity, which you are correct in assuming is usually given as delta T for doubled CO2, the models aren't even the tightest constraint on the range of possible values anyway. If you look at the SkS post on climate sensitivity you'll see that the "Instrumental Period" in Figure 4 actually has quite a wide range compared to e.g. the Last Glacial Maximum. This is because the signal:noise ratio during the instrumental period is quite low. We know the values of the various forcings during that period more accurately than during any other period in Earth's history, but the change in those values and the resulting change in temperature is relatively small. Furthermore, the climate is not currently in equilibrium, so the full change resulting in that change in forcings is not yet evident in the temperatures. In contrast, we have less accurate figures for the change in forcings between the last glacial maximum and today, but the magnitude of that change was so great and the time so long that we actually get a more accurate measure of climate sensitivity from that change than we do from the instrumental period. So it is completely unnecessary to rely on modern temperature records to come up with an estimate of climate sensitivity that is good enough to justify action. In fact, if you look at the final sensitivity estimate that is a result of combining all the different lines of evidence, you'll see that it is hardly any better than what we already get just by looking at the change since the last glacial maximum. The contribution to our knowledge of climate sensitivity from modelling the temperature trend during the 20th century is almost negligible. (Sorry modellers!) So again, if anyone really wants to argue that there is nothing to worry about, they also need a plausible explanation for why the climate sensitivity implied by the empirical data is much larger than what their hypothetical model indicates. And just to be clear:
    And whilst sensitivity may be an output, my understanding is that it is determined by our input assumptions re: the component forcings such as increased atmospheric water vapour (positive feedback) and cloud cover (negative feedback).
    No. It is influenced by some of the inputs that go into the models, but those inputs must be reasonable and either measured or constrained by measurements and/or physics. And the models constrain it less precisely than the empirical observations of the change since the last glacial maximum anyway -- without using GCMs at all we get almost exactly the same estimate of climate sensitivity as what we get when adding them to the range of independent lines of evidence.

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