Tuesday, January 6, 2015

Does the Climate Change Debate Come Down to Trust Me versus Show Me? - Further thoughts on Error Avoidance

Author's Note: This post represents a follow-up to an earlier post on Type I and Type II Error Avoidance and its Possible Role in the Climate Change Debate. For those of you returning to this posting you will note that I have removed several technical paragraphs discussing Type I and Type II errors. In the comments thread, here and elsewhere, it has been pointed out that the introduction was overlong, potentially had issues and most importantly distracted from the topic at hand. The critical point being made was simply that Type I and Type II errors do not operate strictly in an “or” relationship because they address different hypotheses (null versus alternative) and that the tools used to avoid making Type I and Type II errors differ significantly.

 The tools used in Type I error avoidance are centered around an understanding of the nature and characteristics of the populations under study and a general acceptance (by the scientific community) of what represents an acceptable risk of making an error with respect to hypotheses about those populations. The current gold standard in science is the 95% confidence level with a p-value of 0.05. In order to derive an acceptable p-value, certain characteristic of the population must be understood. Is the population best described using the normal distribution? the lognormal distribution? is the population dynamic insufficiently well understood that nonparametric statistics are necessary to generate a p-value? I know at this point of the discussion my statistician friends are pretty much writhing on the floor in agony and for that I apologize. The details of how statisticians evaluate populations involve mathematics that make my eyes bleed and for the purposes of this blog posting are excessive to the task.

The tools of Type II error avoidance are less well-refined (but are getting better every day). They depend more on process knowledge which can include providing a clearer separation between the null and alternative hypotheses and improving our understanding of the nature of the distribution that is being tested. Lacking good process knowledge an increase in sample size will increase the power of an analysis. In order to avoid a Type II error one needs to understand the nature of the problem being investigated and must have developed some reasonable body of process knowledge that allows one to be sure one is looking in the right places. Lacking detailed process knowledge Type II error avoidance depends on the brute force of replication and increased sampling density. As an analogy to my business, while not pretty, if you punch enough holes in the ground you can pretty much find any contamination that is out there.

So how does this explanation relate to my original thesis? It comes down to the nature of the communities under discussion. My initial hypothesis was not about how hypotheses are tested but rather about the nature of individuals who live and work in a world where the differing modes of error avoidance dominate risk-evaluation and resource allocation decisions.

As noted previously, the scientifically acceptable p-value is a feature of a scientific consensus. It involves a degree of cooperation and acceptance of scientific norms that is a part of the DNA of the academic community. In the general academic community there is an inherent trust in the process. Academics trust that the scientific process, when carried out according to the norms of science, will result in the most reliable outcome/predictions. Perfection is not possible but once you reach a certain level of certainty, perfection is not necessary. This level of internal trust (trust that has been tested through peer review) results in a habit of trusting in a group consensus and, some might argue, insular thinking. It unfortunately also can accommodate individuals who take on the mantle of authority from the group to make predictions, even when the predictions may not be fully supported by the findings of the group. In essence the group will often protect their own and keep their arguments behind closed doors (or between the editor and writer). I readily admit that I am painting with a very broad brush and there are mavericks in every group but my observations are based on general characteristics of the community.

Sceptics, on the other hand, work on the underlying Type II error avoidance ethos that says that until you have a good grasp of process knowledge then you had better have a lot of data to back up your pronouncements. They are averse to trusting any process where they cannot see the sausages being made. They need to be able to test the ingredients and even then will want to evaluate the outputs. They view global climate models as “black boxes” into which data are fed and out of which predictions are made. Not being able to assess the contents of the black boxes they demand “more data” in the form of outputs that reflect actual conditions in the world. As we know, in the recent past the models’ predictions have been on increasingly shaky ground. This has triggered a risk-aversion response in the Type II community to ask for the collection of more data and not to act precipitously.

A colleague at work describes the difference as roughly the “trust me crowd” versus the “show me crowd”. The trust me crowd can show that some anthropogenic climate change has happened in the past and that models suggest that future conditions are going to get worse. They produce their documentation via the peer reviewed press and in doing so address all the touchstones of the scientific method. Having met the high bar of “good science” they anticipate that their word will be taken as good.

The show me crowd looks at the “good science” and points out that many historical predictions of doom and gloom (that previously met the test of good science) have been shown to be overheated or just plain wrong. They also point out that the best models have not done a very good job with respect to the “pause”. Given this they ask for a demonstration that the next prediction is going to be better than the last one. This does not mean that they deny the reality of anthropogenic global warming. Rather they are not comfortable with cataclysmic predictions and calls for immediate action prior to a demonstration that those predictions can be supported with something approaching real data.

So once again it comes down to communication. The groups have to step out of their comfort zones and start re-learning how to communicate with each other. Warmists have to emerge from their back rooms and acknowledge publicly what they have been acknowledging privately all along. That these predictions represent just that: predictions. The best predictions possible given the limitations of the system and tools available, but not the certain outcomes suggested by many. They have to make a case why in a world with finite resources, that substantial resources should be allocated to prevent low-probability, high-cost outcomes. Sceptics on the other hand have to trust that fairly reasonable predictions can be made of a complex and chaotic system. They have to listen to the case made by the warmists and maybe even give them the benefit of the doubt. Having read the comments at a number of blogs, that last part may well be the hardest but it is necessary if we are going to re-establish a reasonable dialogue and seek to address this impasse.


  1. "Sceptics on the other hand have to trust that fairly reasonable predictions can be made of a complex and chaotic system. They have to listen to the case made by the warmists and maybe even give them the benefit of the doubt."

    No-one is going to trust the forward predictions of models which can't successfully hindcast the instrumental temperature record without post hoc fudging of aerosol levels and effects to offset an overblown sensitivity estimate which relies on a theoretical water vapour feedback increasing mid tropical tropospheric temperature faster than surface temperature, which is not observed in the real world.

    Your 'have to' imperative seems to be predicated on your conception of the preconditions necessary to meaningful dialogue between warmists and sceptics. Until warmists start having an honest dialogue between themselves regarding the shortcomings of their data practices, hypothesis formulation and statistical techniques, I see little prospect for it.

    As we discovered at Lisbon, until climate scientists agree to the setting up of standards organisations and data agencies with powers of oversight on their activity seen to be independent from those who make observations, form hypotheses from them, and advocate for policy, no-one will be taking them seriously.

  2. I'll make a comment and take a slightly contrary position. In my view - FWIW - there are two aspects to this general topic that we should try to keep slightly separate (although they are related). There's climate science itself (i.e., the scientific understanding of our climate and how it will change under increased anthropogenic forcing) and climate policy (what we should do, if anything, given our understanding of climate science). To a certain extent, I think you've done what many do which is to kind of merge these two things together. Clearly climate policy depends on climate science, but climate science does (and should not) depend on climate policy. I certainly think it would help if people were better able to distinguish between these two topics.

    Here's my contrary position. You say,
    The groups have to step out of their comfort zones and start re-learning how to communicate with each other.
    and I don't really agree. I'm not opposed to better communication between the groups, but I don't see it as all that important or even really necessary.

    For example, from your posts, you appear to be a self-professed Lukewarmer and have said things that suggest that you believe climate sensitivity will be low. That view clearly influences your views on climate policy. What's the point of a discussion if you've already made up your mind? I certainly don't need to convince you that you're wrong. I would just need to convince others. Similarly, you don't need to convince me that you're right, you just need to convince others.

    So, while people hold relatively contrary positions, it's not clear why we should be aiming for better communication. Each group should be aiming to base their views on the best evidence available and if their views are particularly contrary, then presumably one group isn't. Better communication is unlikely to change that, especially if the information is readily available to all.

    I'll add a final comment. You appear to be critical of those who you claim believe in CAGW and, hence, that climate sensitivity will be high. Given that you appear to believe that it will be low, it's hard to see why your position differs fundamentally from those who believe it will be high. Also, since you appear to be someone who does risk assessment, it might be worth considering that some of those who you claim *believe* in CAGW, are simply concerned that climate sensitivity *might* be high and are concerned about the possible consequences if it does turn out to be high. This isn't the same as believing it *is* high.

    1. Sorry, should have been climate science does NOT (and should not) depend on climate policy.

    2. AndThen: you write: "Clearly climate policy depends on climate science, but climate science does (and should not) depend on climate policy."

      That is the ideal. But what has occurred over the past 30 years is precisely the opposite. I think a lot climate scientists in the 80s thought that global warming was a very plausible theory and if it was, it would require huge investments in abatement and adaptation. The IPCC was created and essentially merged these scientists, many of whom had a strong interest in environmental issues, with policy makers, making the two dependent on eachother. The policy makers loved the theory and demanded more certitude, which gradually was provided for them by the scientists, although no real compelling proof was ever provided. Since then trillions have been spent on mitigation, some of it sensibly, but much of it not, given that we don't know if it's really necessary. If, for example, the warming is 1.5 degrees over a century, will much of the money being spent today prove to have been spent wastefully while other human problems of enormous importance have been neglected?

      I think enormous pressure has been put on the coterie of scientists who have given us the theory of global warming (and as a consequence the policy that derives from it) to provide the kind of science that enables the policy makers to vigorously intervene in economic and energy matters. I believe that pressure has been applied to come up with the "correct answers" not only by policy makers and NGOs heavily invested in environmentalism, but by the scientists themselves upon one another. One sees this in the Climategate emails.

      The proxies need to be updated. All the data "proving" the theory needs to be archived in open archives. The government of the United States needs to appoint a commission to review all the science, the proofs, and the arguments for and against. The EPA is hopelessly locked into the theory as evidence by their ruling on CO2. A comprehensive, independent investigation on behalf of American taxpayers and energy consumers, which is to say all of us, needs to be conducted on not only what has transpired with the science, but the current state of the science as well, which as we know, did not adequately predict the pause in temperature rise over the past two decades.

    3. Doug,
      But what has occurred over the past 30 years is precisely the opposite.
      You seem remarkably certain. What p-value did your analysis produce ;-)

    4. ATTP, it’s absolutely true that policy should not affect the science. The effect is the other way round. If all you want is a tick in a box then current climate science is fit for purpose. However the greater the policy changes you demand the higher the bar is set for the science. Action is a measure of whether the science is convincing or not, not whether it is right or wrong. In demanding “show me” sceptics are saying that for the level of action you demand, your science isn’t good enough and “trust me” is of only limited value.

      Too often climate issues are painted as black and white. It’s all shades of grey including the “trust me”, “show me” concept. Humans do not work on binary, we’re creatures of the analogue. Like the climate, our outputs (actions) are affected by a great many inputs (evidence, experience, personality, circumstance, etc). If all our inputs are analogue why would you expect out output to be digital (will act/won’t act)?

    5. Tiny,
      I agree with your second paragraph. This is clearly not a black and white issue. In fact, that is one problem I have with the attempt by our host to define this in terms of Type I and Type II errors. The issue is really a continuum of possibilities. Climate change won't simply be catastrophic or completely fine. Our policy options aren't simply to mitigate or adapt.

      I'll disagree with you on a few things, though. You say
      However the greater the policy changes you demand the higher the bar is set for the science.
      I think this depends on the situation. We're really in a risk assessment situation. We as a society get to decide what we should do, if anything. If science is suggesting that there are potentially severe outcomes if we continue to increase our emissions, we get to decide if we should act to minimise the possibility of those outcomes becoming reality. We can certainly demand that the scientific evidence becomes stronger before we do anything. That demand, however, doesn't change the possibility of those outcomes becoming reality. If we decide not to act and the severe outcomes do happen, then we can't blame the scientists for not having stronger evidence when it was demanded. They can only provide the best that is available at any instant in time.

      You also say,
      In demanding “show me” sceptics are saying that for the level of action you demand, your science isn’t good enough and “trust me” is of only limited value.
      I think this is essentially a strawman. I don't think anyone is demanding anything and I don't think that climate scientists are saying "trust me". The evidence is available for you to assess yourself if you wish. You, also, are as entitled to argue against acting as anyone is to argue for acting. Others who are proposing policies with which you disagree are not really demanding anything. They're simply exercising their democratic right to express a view as to how we should respond to the risks associated with climate change. You can express a completely different view if you wish.

  3. The second part of your post about "trust me" versus "show me" is good.

    But the first part in which you respond to John Shade is not.
    John is quite right that as you reduce the chance of making one error you increase the chance of making the other.
    You are wrong that sceptics work on the Type II error avoidance ethos.
    The sceptics think that the warmists have made a Type I error in over-diagnosing man-made global warming.
    This is such a simple point that it must be a communication problem - the communication problem is 'worse than we thought', since sceptics and lukewarmers are talking past each other.

    Here are several people at BH saying you've got it wrong:

    It seems to me that the warmist (fear mongers) are willing to accept false-positive global warming "tests" as justification to implement "treatments" to reduce C02, even though there it's not certain there is an actual "disease" present (environmentally catastrophic warming) that warrants the "treatment".
    In essence the warmists don't seem to be in the least concerned that they may have a "false positive" (oldfart61)

    Unfortunately completely ass backwards.
    It's the skeptics who are questioning the IPCC / climate establishment's demonstrable false positives -produced by 150+ models and a fundamentally flawed hypothesis. (tetris)

    Not sure the false positive/negative thing isn't backwards. A thought provoking albeit backwards post. (Rud Istvan)

    I would say that a model that finds global warming (i.e., an increase in the global mean surface temperature) where there is none, is an example of a false positive, and the premise behind the article and all the comments here so far is simply wrong: The warmists are TOUTING a false positive, not trying to avoid it at all. (Harry Dale Huffman)

    I'm not sure about his comments about academia having strong procedures for avoiding type 1 errors - if that were the case we wouldn't be where we are today. (Paul Matthews)

    The so-called sceptics, in other words, act somewhat as if they wish to avoid the Type I error: which in our simplistic analogy, is the error of raising a false alarm. Alarmists on the other hand act somewhat as if they wish to avoid the Type II error, which in our
    analogy is the error of failing to raise the alarm when in fact there is a fire. The author of the piece quoted in the above post has got this back to front. (John shade)

    1. etzpm,

      I have taken your comments to heart and have removed the earlier part of the post. It was overlong, but unfortunately not long enough to go into sufficient detail to clear up some of the more esoteric issues around Type I and Type II errors.

  4. I am not a statistician; just a df engineer (ret.).
    Are not "p" and error types relating the sample to the subject population? It seems to me that statistics can only apply to the sampled population, so one must be careful when considering events outside the sampled population.
    In climate science, the population is historical, and the future is outside of that population. Any predictions are the domain of the statistician, and rely on the understanding of the system and assume that future behavior will be the same as the past.
    The sample can accurately represent the historical population (p<0.05) and completely miss tomorrow if the history is incomplete or not repeating. In manufacturing, this is why you keep sampling even if past samples have all been acceptable. IOW, things might change! If the sampled population is not representative of future behavior, your model is wrong, even with a p<0.001

    1. Slywolfe, Your question is quite cogent and goes to an area I have not been willing to touch in these posts, the concept of "errors of the third, fourth or fifth kinds". They involve questioning whether the data is appropriate to actually answer the hypothesis (asking the wrong question, using the wrong null hypothesis to answer the question and/or collecting the wrong type of data to answer the question). The Type I/Type II error formulation is useful but is not at all complete.

    2. Thank you for interpreting my post as a question.

  5. What must be understood is that this subject of global warming, or climate change is not like any other science, in that it is now being driven by politicians and others with a massive financial and political interest. The initial work may have been done in a truly impartial manner, but once it became politicised all that changed. One has only to read some of the leaked emails to realise that the IPCC is not an impartial body. What is happening is that those supporting the case for "climate alarm" are attempting to exaggerate every example that bolsters their case, while those who dismiss the case will do the opposite.

    Another point is that if the "problem" of climate change is not going to materialise for even 50 years (let alone 100 years or more), then very few people will accept that it must be tackled now. This makes this subject a unique issue. Scientists making the case for massive expenditure to lower CO2 emissions can do so safe in the knowledge that they will be retired before we can have any "certainty" that they are wrong. The same is true of scientists saying that there is no problem.

  6. They have to listen to the case made by the warmists and maybe even give them the benefit of the doubt. Having read the comments at a number of blogs, that last part may well be the hardest but it is necessary if we are going to re-establish a reasonable dialogue and seek to address this impasse.

    I don't understand you mean by "giving them the benefit of the doubt"?

    If you mean work on the assumption that they are working in good faith (until shown otherwise), then sure.

    If you mean work on the basis that they have a point, then no.

    I listened to years to Marxist economists that were utterly convinced that they were right. I gave them absolutely no "benefit" of any doubt that they might be. I've similarly completely ignored many "experts" in child rearing, most "educationalists", all proponents of astrology, homeopathy, reflexology etc. It's not a sign of flexibility to be persuaded to listen to idiocy, it's a sign of idiocy.

    I'm happy to accept that adding CO2 warms the atmosphere, and don't deny anything that resembles solid physics or chemistry. I listen to the arguments of those that believe the consequence of our CO2 production may be catastrophic and remain utterly unconvinced on a couple of key points (the positive water vapour feedback and the long residence time of CO2 in the Bern model in particular).

    Note that I accept that I might be wrong, and they may be right. But that doesn't mean I'm going to move towards their position -- any more that accepting that I might not choose the best political party at an election means I shouldn't vote in case I'm wrong. I'll listen to the catastrophists -- just as I listen to what all political parties have to say before I vote -- but once done and unpersuaded I don't move towards them.

    So what "benefit of the doubt" are you proposing I give those that think that the warming may be catastrophic? Because I can't see any I'm prepared to give.

  7. "The show me crowd looks at the “good science” and points out that many historical predictions of doom and gloom (that previously met the test of good science) have been shown to be overheated or just plain wrong. "

    Show me.

    Show me some "predictions of doom and gloom" in the earth science literature. Not in the press. Not in the breathless press releases by the university publicity office. In the science. With citiations. Please.

    1. I'm not sure why the odd restriction of the "earth science literature". The public doesn't care whether it was in the "earth science literature" they care that the statement was made by a "well-renowned scientist". In that class I would suggest the highest profile document written was "the Limits to Growth" by the Club of Rome and virtually the entire academic output of Paul Ehrlich since 1970. A search of "climate catastrophe" on Google scholar nets 2900 hits, "peak oil" nets 23,100 hits .

    2. Well, the critique is directed at "the good science", so I read the assertion implictly as a claim that **formal predictions** were made by in **peer reviewed articles** regarding **physical climatology** climate that have **proven false**.

      I suppose there are a few. But I am also sure they are not so pervasive as you seem to want to believe.

      As I said before, what Ehrlich says is no concern of mine. More to the point, he does not in any way represent physical climatology. What he has said does not reflect on whether "the good" climate science is excessively alarmist, excessively complacent, or roughly balanced in its message.

      Shall I take this as an admission that you have nothing to show me?

      Anyway, this is exactly Oreseks' point. The claims made in the literature are extremely cautious in the scientific sense. What actual climate experts think is going to happen goes far beyond what IPCC WG I says.

      Of course, what IPCC WG I says is enough to motivate action. But not if further discounting happens in the other working groups and even more in the political process. This is exactly the consequence of the fear of false positives as Oreskes claims.

      Coming back to your point about false positives and false negatives I am baffled as to what your argument is about. If scientists are systematically avoidant of discussing things that they are less than certain about (built into the culture and the process as you say) is it not more likely that real risks are being ignored than that false risks are being trumpeted? That is, I find Oreskes argument at least cogent, whether or not it's true.

      I'd like to see where you are coming from but I don't really see your point.

    3. I too see no reason to restrict the search to earth science, but to humour you here goes:

      Hubbert, M. King (June 1956). "Nuclear Energy and the Fossil Fuels" the kick-starter on the imminence of Peak oil. This was followed by many, many prognostications of economic doom.

      There's also a long history of massively overheated claims about the desertification of Africa. They can be found discussed in Drought, Desiccation and Discourse: Missionary Correspondence and Nineteenth-Century Climate Change in Central Southern Africa Georgina H. Endfield and David J. Nash The Geographical Journal Vol. 168, No. 1 (Mar., 2002) for particularly early examples, but there's been plenty of wailing and gnashing since too, much of it peer reviewed.

      If we allow for accurate reporting (so, agreed, not a press release and not mistranslated by an idiot reporter) what scientists say in public can be even more peculiar. This "we're all going to die" one is a favourite of mine: http://phys.org/news196489543.html .

      I can find more Michael, but I've run out of energy.

      Sadly, the earth sciences are not as free of excessive pessimism as you would like to believe.

    4. King was a petroleum engineer, and his claims were not peer reviewed. Fenner was a virologist. And your other example is 19th century geographers!

      Physical climatology is a young discipline but a rigorous one, and it is our claims that are at issue. You have zero examples so far of explicit predictions in climate science that have been invalidated.

      I could defend Hubbert and for that matter Ehrlich and the Club of Rome. This Fenner character is new to me and he seems like he probably cracked in his later years.

      I am asking whether the implicit claim that there are broken predictions in climate science holds water. I am not asking whether scientists over the centuries have said silly things in unguarded moments, which I will gladly stipulate.

    5. Oddly enough I don't think I could come up with a better example of how the specialist academics "don't get it". You are implying that the general public has the capability of distinguishing between a "physical climatologist" and the 100+ PhDs who sat on the board or were authors for the Club of Rome in the 1970s and 1980s. That Paul Ehrlich, the most famous talking head academic of the 1970s on the topic of global gloom and doom didn't have an effect on the public's trust in scientists? Every scientist who jumps out and cries wolf makes it harder for the rest and there are way too many politically active academics out there. The part I find most entertaining is that you completely ignored the fact that Google scholar shows over 23 000 hits for "peak oil". That includes literally hundreds of peer reviewed articles in good journals and chapters in technical publications that addressed a topic that has now been shown to not be relevant any time in the foreseeable future? This is why it is difficult to build public trust in an equally challenging subject.

    6. Blair,
      Papers on "peak oil" are not papers on physical climatology. What Michael is asking you is whether or not you can actually provide examples of peer-reviewed papers that were making predictions of climatological doom (not economic doom) that has not actually come to pass (i.e., prediction that something severe would have already happened). I don't think you can, but feel free to prove me wrong (and I did say papers not paper).

      Sadly, I think this discussion is going as I rather expected. One reason I didn't want to continue the discussion that started on one of your previous posts was because your response was so typically "skeptic"-like (and the inverted commas are intentional) that I couldn't see any point. However, you do seem to genuinely want to be reasonable, which is what lead to comment on this post.

      However, I think you're at a cross-roads. You can double down and head towards a home at WUWT/Bishop-Hill etc, or you can recognise that you've based your views more on reading blogs and poorly written online articles, than on reading the actual scientific literature. Given past experience, I'd be willing to bet on the former, but - again - feel free to prove me wrong.

    7. I wrote about how the public views "science", "good science" and gloom and doom predictions by recognized scientists. Dr. Tobis is the one who read those words and replaced them with physical climatographers. Dr.Oreskes is not one but she seems to be making a name for herself on the topic. The biggest name in the field for a decade was a former Vice-President who had no formal education in the field and was feted by the scientific community and hosted by academic institutions and academic bodies.

      I have no pretensions in this field. Read my most recent post to see where I actually sit because in this case your straw man actually has an opportunity to talk back and correct your misconceptions, misquotations and re-directions.

    8. I was presuming that the "show me" crowd was capable of finer distinctions than that. By claiming to be a chemist I presumed you claimed some scientific capacity.

      Are we discussing climate science or are we discussing its caricature by people who have no intention of investigating its content?

    9. Blair,
      have no pretensions in this field. Read my most recent post to see where I actually sit because in this case your straw man actually has an opportunity to talk back and correct your misconceptions, misquotations and re-directions.
      To be a strawman, I think I would have had to have stated something as being true, rather than expressed my opinion/view about something. You, of course, are welcome to completely ignore, and disagree with, my views (as many do) but that doesn't mean I shouldn't hold them.

      As Michael implies above, I was assuming that we were discussing actual climate science not the caricature of climate science that is often seen in the media and on blogs. If the latter is what you were actually talking about, then fine, it is true that some base their views of climate science on what they read in the media and on blogs and there are indeed people who have expressed views that are extreme and don't help rational debate. That has little bearing on actual climate science, though.

    10. We have entered the "no true Scotsman" territory.

      "Show me some "predictions of doom and gloom" in the earth science literature"

      When done, they need to be peer reviewed. Or aren't true earth sciences. Or too old. Those are what I found in five minutes with no access to any academic papers (because the older predictions aren't on-line it is pretty hard to find them for a person living in a town with no earth sciences library).

      But the real issue is that the "trust us" crowd will do anything but admit that the earth sciences are just as prone to being spectacularly wrong with their predictions as everyone else. We have to trust them that they aren't into gloom.

  8. Frequentist statistics is important in clinical trials and some other sorts of experimental design, but it is not the whole of science.





  9. "It was a very brief exchange and Dr. Trenberth is a soft speaker, so I can’t give you exact quotes (note to self: turn your recorder on before engaging with big whigs), but he did affirm his earlier statement and then mentioned something about a ‘type II error’ and the fact that many scientists go with a more conservative position than they otherwise would because they are afraid of being “called out”.

    I took this to mean that scientists purposefully take a low ball position or hold back in highlighting the “tail risks” of certain projections because they don’t want to be called an “alarmist.” Basically, if the impact or temperature rise or whatever is larger than expected, they won’t get called out for underestimating the outcome as much as they would if they overshot the response and it didn’t manifest itself at the estimated time or turned out to be lower than expected. I later checked out what a Type II error was. It’s a little over my head (I’m a liberal arts-educated simpleton), but – based on my reading – it is basically assuming there is no connection between two phenomena when there actually is a connection."


    – See more at: http://climatechangenationalforum.org/im-not-a-scientist-but-you-poster-blows-my-mind-highlights-bloopers-at-agu14/

  10. Here is some gloom and doom:

    "While warmth early in the millennium approaches mean 20th century level, the late 20th century still appears anomalous: the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium."

    1. That has not been refuted; nor is it "alarmist".

  11. The modus operand is this. The IPCC puts out a vague waffly tome every 5 years that makes a prediction ranging from so-what to were-all gonna-fry, and tells us it's the result of expert judgement from clever people reviewing the peer reviewed literature, (glossing over the fact that much of the content of their waffly report is grey literature commissioned and/or written by WWF/Greenpeace NGO activists).

    The talking heads like Chris Field (Stephen Schneider's protege) and other alarmists then line up at a news conference looking suitably grim faced and talk up the most extreme end of the prediction range to the assembled compliant SEJ activists masquerading as journalists, who then pump up the volume in the media.

    Then Michael Tobis turns up at venues like this to issue the plausible deniability statement.

  12. I had no idea that I am playing such a crucial role. Thanks for the vote of confidence.