One of the aspects of the climate change debate that I find most baffling is how seemingly intelligent people can waste so much of their time arguing over whether or not the acronym ‘CAGW’ was invented by the sceptics, or indeed arguing which side first used the term ‘catastrophe’ in the context of climate change, or even who uses it most. The accusation seems to be that sceptics have set up a straw man by first asserting that the alarm lying behind initiatives such as Net Zero is based upon a wish to avert catastrophe, and then suggesting that the science fails to provide sufficient evidence of such an outcome. The argument is that ‘catastrophe’ is not a scientific term and so has never entered into the scientific debate. Consequently, CAGW and all talk of ‘catastrophe’ is just the sceptics’ way of keeping an argument going long after the actual science has been settled. Those who think this debate matters so much seem to expend a lot of effort seeking to establish historical precedence and engaging in seemingly endless arguments regarding the meaning of words. I profess to being somewhat unmoved.

Climate change itself is deemed a big deal. It has to be, otherwise why are people advocating profoundly transformative changes to the way we live our lives? Why are people on the streets, protesting under the banner of ‘Extinction Rebellion’? And why are scientists signing petitions expressing support for them and threatening to go on strike if more isn’t done by the politicians? If all of this isn’t in order to avert something that can reasonably be referred to as a catastrophe, then I don’t understand what it is for. That is why I am quite comfortable with the idea that the great debate must be with regard to anthropogenic global warming that is potentially catastrophic, and I certainly see no reason why I should not abbreviate this concept using the acronym CAGW. It doesn’t matter a jot who coined this acronym or whether ‘catastrophe’ is a sufficiently well-defined term. The point is that ‘catastrophe’ is part of the patois on both sides of the debate and, as such, it is serving a useful purpose.

That certainly seemed to be the position held by IPCC Lead Author, Prof Robert Muir-Wood when he wrote his book on ‘How we can stop manufacturing natural disasters’. It’s a book full of examples illustrating the perils of such disasters and how mankind has, or has not, adapted to the risks posed. And what did he call that book? He called it “The Cure for Catastrophe”.1

Now, I’m sure that the good professor is as aware as the next person that ‘catastrophe’ is a subjective term. But that didn’t stop him adopting it for the title of his book, and then repeating it on just about every page. He even coined the term ‘Catastrophysics’ in order to use it as the heading for his chapter 3. For Muir-Wood there is no doubt; ‘catastrophe’ is a very useful word for his purposes.2

In fact, if sceptics truly are the group that must take responsibility for the promotion of the term ‘catastrophe’ then this could actually be very much to their credit. If the word ‘disastrous’ had been chosen (hence DAGW), a similar sentiment might have been conveyed; however, that would not have quite captured the essence of the situation. As Muir-Wood explains when discussing the great Lisbon earthquake of 1755:

“Across Northern Europe the earthquake inspired a shift from a philosophical ‘best of all worlds’ optimism, ruled over by a beneficent God, to a new, darker world order of rational scepticism. The contrasting old and new worlds are captured in the original meanings of the terms ‘disaster’ and ‘catastrophe’. ‘Disaster’ derives from the Greek for an ill-fated, or ‘bad’ star—in Italian, the dis-astro. ‘Disaster’ captures the essence of astrology. A conjunction of planets, or the passage of a comet, triggers a calamity on earth. ‘Catastrophe’ describes the final resolution of the story in a Greek drama. In a tragedy by Aeschylus or Euripides, within the ‘catastrophe’, one or more of the main characters will die. The catastrophe is the inevitable consequence. The catastrophe is the moral.”

This is indeed a useful distinction to be made and Muir-Wood does so throughout his book by emphasising the human factors that court calamity. It is in that sense that we ‘manufacture natural disasters’. The calamities that are posited for AGW are certainly catastrophic in the sense that they are anthropogenic and deemed inevitable if nothing is done about it. In this sense, ‘catastrophic’ has a meaning that is relevant to the debate, whichever side you are on. However, there is another aspect to the word that bestows upon it great utility – it defies a singly quantified definition.

How big is big? I used that word earlier when saying that climate change is deemed a big deal. But what size of deal are we talking about? And does the fact that ‘big’ may imply different sizes depending upon context and one’s perspective mean that I should not use the word? It is vague and subjective – like ‘catastrophic’ – but is that any reason to veto its use? In fact, the English language is full of such vague words; they are called degree adjectives, and without them English would be impoverished indeed.

There are some who view vagueness in language as a linguistic anachronism – a legacy of our primitive past, when sophistication and precision provided little evolutionary advantage. I disagree. Our love of vague terms is not a failure to divest ourselves of a bad habit. On the contrary, the vagueness lying at the heart of our language provides utility that enables us to operate effectively and efficiently in an uncertain world. ‘Catastrophe’ is not a degree adjective but, as a noun, it has a quality that enables its use in a variety of contexts. Calamity is involved but one should not be demanding a particular scale of calamity before the term ‘catastrophe’ can be applied; it will always be context-specific and value-laden. This remains the case even when one takes into account definitions of the precautionary principle that talk of irreversible changes and ‘serious’ environmental damage.

Given its qualities, it is no wonder that ‘catastrophe’ features prominently in the rhetoric of advocates.3 So when sceptics refer to ‘CAGW’ they are using the term ‘catastrophe’ to encourage others to question whether the concern that is energising the advocates justifies what they advocate, and whether their conception of the calamity can be justified by reference to the science. ‘Catastrophe’ is a useful epithet for that purpose.

Of course there are other equally vague and subjective words at everyone’s disposal, and even scientists are not averse to using them. Take this quote, for example, from Muir-Wood’s book:

“I was there, in Exeter, when the German climate scientist Hans Joachim Schellnhuber’s proposal of a ‘guard-rail’ rise in global temperature of 2 degrees Celsius [3.6 degrees Fahrenheit] was declared to be the definition of ‘dangerous’ climate change.”

Danger is another of those things that can come in degrees (no pun intended) and so, like the word ‘safe’ when used in safety engineering, it is more useful when qualified. In the same way that safety engineers talk of ‘sufficiently safe’ or ‘acceptably safe’, rather than just ‘safe’, one should talk about ‘too dangerous’ or ‘unacceptably dangerous’ in the context of global warming. The ‘guard-rail’ of 2 degrees Celsius is an arbitrary threshold set to delineate the acceptable from the unacceptable. We can argue about its scientific foundation (and worry that any arbitrary threshold is vulnerable to the sorites paradox) but, at the end of the day, a vague and value-laden word is being used here.

Systems safety engineers dislike vagueness because it reflects uncertainty. Nevertheless, as long as they continued using adjectives such as ‘safe’, ‘reliable’ and ‘predictable’ in their safety arguments, they had to accept that linguistic vagueness was playing a central role. And rather than suffering unnecessary embarrassment, they recognised the importance of this and worked with it. Safety cases are written for an audience that was brought up on natural language and the one thing that linguists can say for sure is that natural language is riddled with vagueness. But the engineers are still perfectly capable of constructing a reasoned argument and acting upon it, enabled rather than challenged by the subtleties and mysteries of linguistic vagueness. The same applies to the terminology used in the climate change debate. It is useful to spend time investigating the science behind a cause and effect, but it is a colossal waste of time trying to glean a straw man from the sceptics’ use of a term that has so much ubiquity and utility.


[1] First published, 2016, Oneworld Publications, ISBN 978-1-78607-005-0.

[2] Muir-Wood is also the head of a firm (RMS) that specialises in ‘catastrophe modelling’. Not such an unscientific term after all.

[3] For example, Nicola Sturgeon has warned that failure to meet targets agreed at the COP26 summit in Glasgow would be “catastrophic” for the planet.


  1. John,

    I’m not really sure whether or not alarmists object to the use of the word “catastrophic” in the context of Anthropogenic Global Warming. If they do object, I can’t see why they should, since as you point out, demanding huge changes with massive costs (financial, environmental and societal) seems rather pointless unless they believe that the changes are justified because they will avert something pretty catastrophic.

    Some of them do seem to object to being termed alarmists (though I’m not aware that they share the same aversion to to the use of the word “denier” when referring to those who question their narrative). Again, however, I can’t see why the use of the word “alarmist” might be considered offensive, inaccurate or derogatory – after all, if they aren’t alarmed and/or seeking to alarm others, why do we need to incur the costs and inconvenience/disruption inevitably associated with the whole “net zero” project? Why do so many of them support those – like XR – who adopt extreme language and positions?

    All in all, the use of “alarmist” and “catastrophic” in the context of the debate surrounding climate change seems fair enough to me.


  2. In my brief career as a commenter at the Guardian 13 years ago I used “CAGW” all the time, because everyone else did. I was debating with some of the finest minds on the “nervous” side of the debate, and never once did anyone object that climate change wasn’t catastrophic.

    How could they? What could they say? “We never said it was catastrophic. The reason we come here to insult you and get you banned from comments on the half dozen or so articles the Guardian published every day is because a rise of 0.17°C per decade in global temperature is jolly interesting and you’re making a mockery of it.”

    Liked by 1 person

  3. I left a comment at Jit’s article on Granny therapists which I can see but which hasn’t turned up in the “New Comments” column. Can anyone else see it? In it I mentioned in passing a book by one James Hansen called “Storms of My Grandchildren: The Truth About the Coming Climate Catastrophe and Our Last Chance to Save Humanity.” Could James be one of these denier types out to discredit climate science by raising the Catastrophe straw man argument?

    Liked by 1 person

  4. Geoff: That absence from “New Comments” is very weird indeed. This takes you there:

    Click here!

    The same applies to your latest comment about the absence. But the problem’s now fixed, even as I explore it. What they call a Heisenbug?

    I have no idea what was going on with this. Please accept my apologies as WordPress wrangler-in-chief. Annoying, if not fully catastrophic.


  5. Some discussion on the issue of ‘CAGW’ usage, and some history of the term too, is here:

    As you note, the term evokes strong feelings on climate blogs and forums in recent times, but this wasn’t always so, and maybe Geoff’s experience is old enough to be within those times. Given that not only usage of the term itself, but the emotive baggage and polarisation that eventually grew upon it, are emergent not only across both sides in the (miniscule) blog/forum domain, but also from much wider usage, then any talk of awarding invention or current meaning to anyone in particular, or any ‘side’, is I think pointless.

    I think the main issue is that there is a completely different dynamic in the blog/forum world, to that in the enormously larger public domain. In the latter, ‘catastrophe’, acronymed or not, won the emotive meme battle hands down. In the former, enough rationality survives that ‘catastrophe’ certainly did not win a narrative battle, could not win, because (being indeed scientifically wrong in the context of both mainstream and sceptical understanding), it is suppressed within this tiny and controllable and far more knowledgeable environment. Albeit supressed sometimes with a too-ready cudgel.

    So when sceptics use the term on a blog, they are typically referring to its ubiquitous usage in the public domain, including virtually all public authorities, and a very few vocal scientists who disagree with the IPCC (thinking it far too conservative). This usage indeed contradicts the mainstream / IPCC science, yet indeed dominates. But when the orthodox, for want of a better word, see it on a blog, they automatically interpret it as a reference to the mainstream science, which per above indeed casts this wrongly, and they do not assume that sceptics are referring to the ubiquitous public and public authority usage, which for instance is still the main (and measurably so) influence upon policy.

    The issue could be solved simply by always stating the context; AR5/6 for instance no way no how represents a certain global catastrophe (‘CAGW’ typically carries the ‘certain’ meaning in its baggage too), hence referring to IPCC science as ‘CAGW science’, is indeed wrong. But referring to the IPCC *leadership* as essentially ‘CAGW merchants’, is right.

    While engineers can indeed stay on top despite the vagueness of terms, only above a certain threshold. And what is in charge in the public domain is a culture, which revels in – so to speak, it is not of course sentient – the (especially emotive) vagueness that allows for its continued evolution and the avoidance of reality. All that lovely vagueness you describe, is sugar-rush for a culture.


  6. Mark,

    Yes, I believe ‘alarmist’ is another of those bugbears. It is said that ‘denier’ and ‘alarmist’ should be considered equivalent — either equally literal or equally derogatory. Well, I will assuredly hold to that view just as soon as I come across the term Holocaust alarmist.

    Liked by 1 person

  7. Andy,

    I am sure you are right about vagueness being a ‘sugar-rush’ for culture. I also take your point regarding the distinction to be made between scientific references to ‘catastrophe’ and those made within a wider culture.

    Incidentally, thank you for reminding me about your article posted at Climate etc. Believe it or not, I had forgotten about that. Even more unbelievably, I had forgotten that you and I engaged at the time in one of those debates that I have since come to regard as a pointless waste of time. Well, not exactly pointless because it centered upon our disagreement as to whether certitude dominated the CAGW meme (you said ‘yes’ and I claimed ‘no’). Anyway, the ensuing debate was lengthy and at times a little tetchy and I have no appetite to resume. I will say this however: the classical definition for ‘catastrophe’ does require the inevitability of calamity, so with that sense of the word in mind only, I would now concede the point 🙂

    Liked by 1 person

  8. I like – or rather do not like – the term “manufactured natural disaster.” If natural, the disaster is not manufactured. A wider dig at industrialised civilisation? [What relevance does the Lisbon earthquake have in this thesis?]

    Apocalypse is another word that does not mean what we think it does, but we all know what is meant when it is used.

    Personally I do not think “alarmist” is half as insulting as “denier.” Deniers might score the threat as 0 on an damage-by-AGW scale running from 0 to 1, and [I think] the appropriate opposite would be 1, absolute destruction. 0.3 on this scale might cause alarm, but 1 causes “catastrophe.” I like to think that, if I believed the threat of AGW was worse than its cure, I would not call sceptics “deniers.”


  9. Jit,

    The natural part of an earthquake disaster is the earth shaking. The manufactured part is the use of building materials and construction techniques that are not suitable for earthquake resistance. The Lisbon earthquake was unusually intense, however, and exacerbated by a tsunami and multiple fires. The death toll was also down to the fact that it occurred on a very holy day in which most of the inhabitants were congregated in churches that would have been more protective if they had been built out of Lego. Other examples of ‘manufactured’ natural disasters would be building on flood plains, farming in the rich soils at the foot of a volcano, undue confidence in tsunami defences, etc. In all cases the naturalness of the ensuing disaster can be compromised by a failure to heed warning signs or to engage in false economies.

    The word ‘catastrophic’ is not usually considered to be a degree adjective since one does not usually use the phrase ‘very catastrophic’. Instead, it has an ambivalence that is disambiguated by context and agreed values. I think, for the most part, we seem to be proceeding as if a global catastrophe is on the cards. That’s a big fat ‘1’ on your scale – an assumed obesity that is well worth challenging when the cure’s downside approaches unity.

    Liked by 2 people

  10. Readers might be interested to know that there is a distinction in ecology between “disasters” and “catastrophes.” The line may be blurry, but the difference is that disasters exert evolutionary pressure but catastrophes do not. The examples given in my old textbook are New England hurricanes as disasters – changing the forest tree community in favour of shorter, faster maturing species – and Mount St Helens – a volcanic eruption that is too infrequent to cause selection pressure, so that the community that grows back will be the same that existed before.

    My own example of an ecological disaster on a UK scale is the practice of burning in the uplands, which has transformed the landscape by selecting in favour of heather.

    Applying this in human terms, a disaster would be frequent enough that survivors should expect to experience, but by planning, be able to avoid the worst effects of, the next similar event. A catastrophe in the Lisbon 1755 sense probably did not change people’s attitudes. People are willing to live in areas where they know a catastrophe is waiting to happen, presumably based on the theory that it is unlikely to happen any time soon. One might think that is not the case with respect to disasters, but then we see the ongoing development in fire-prone habitats in e.g. California, so maybe not.

    I wonder if Muir-Wood also noted the benefits that had accrued to the denizens of these dangerous places in the decades or centuries preceding the disaster/catastrophe? [Perhaps I should read the book to find out.]

    Liked by 1 person

  11. Jit,

    The evolution angle is a very interesting one. I suppose from that we can define ‘catastrophe’ as a disaster that a community cannot learn from because it has been wiped out. I suppose this emphasises the contextual nature of the definition since unaffected communities can still learn from the experience. The 1755 earthquake, for example, had a profound impact on the rest of Europe in that it heralded the dawn of a rational scepticism as far as natural disasters were concerned. Voltaire, in particular, challenged the idea that this was all in the lap of the gods. Meanwhile, the thousands who perished could no longer give a fig. I guess the catastrophe narrative that climate change sceptics find most unconvincing is the one that tells of an evolutionary catastrophe for all mankind.

    Muir-Wood does acknowledge that a bargain with nature is often involved in which supposedly tolerable risks are taken in order to reap some benefits. However, I can’t say it is a main theme of the book.

    Liked by 1 person

  12. John –

    > It is said that ‘denier’ and ‘alarmist’ should be considered equivalent — either equally literal or equally derogatory. Well, I will assuredly hold to that view just as soon as I come across the term Holocaust alarmist.

    Interesting. This is basically the issue I wanted to discuss with you on a previous thread (see my comments about “agendas” and about dfhunter’s comments and your response to them), but you declined to engage. I guess it wasn’t apparent to you that this is essentially exactly the kind of dynamic I wanted to discuss.

    Imo, the terms are pejorative labels that do nothing to actually further engagement. Imo, they’re the product of identity-protective/identity-defensive cognition and are “signals” that speak to who people are, not what they think.

    It’s also interesting that the rational used to defend their use (essentially, something like “Why would anyone object to their use, they’re just accurate descriptors”) is basically the same on either side of the climate change divide.

    It’s also informative that on both sides, offense is taken to the pejorative connotation, austensibly because of the principles involved (something like “if they’re calling you names, you must be in the target.” or “Of course they are reduced to ad homs, because they realize just how bankrupt is their scientific argument.”) yet there’s little to be seen in the way of non-selective application of that principle to the group to which people identify.

    Informative because that kind of selective reasoning is exactly what one would predict on the basis of motivated reasoning, confirmation bias, fundamental attribution theory, or other similar frameworks of cognitive biases.

    Seems to me that your comments on this thread, and your reaction to the Mark’s comments, make it clear that you are, in fact, distinctly embedded within the identity-related cognitive processes at least in some fashion. So the challenge I offered to you in the other thread was to explain why, since you’re so deeply embedded in the identity-related cogntitiion in some ways, you’re so confident that you’re so completely outside those biasing processes when you deal with such complex contexts, with so much episremic uncertainty, as climate modeling.


  13. Joshua,

    >”I guess it wasn’t apparent to you that this is essentially exactly the kind of dynamic I wanted to discuss.”

    No, it was perfectly apparent to me what you had preferred to discuss, as was the fact that it was off topic on a thread that was discussing a mathematical detail regarding the technicalities of uncertainty analysis.

    >”So the challenge I offered to you in the other thread was to explain why, since you’re so deeply embedded in the identity-related cogntitiion in some ways, you’re so confident that you’re so completely outside those biasing processes when you deal with such complex contexts, with so much episremic uncertainty, as climate modeling.”

    I’ve already answered that question fully. I had no ‘identity-related cognition’ when I first developed my understanding of the mathematical issue and I needed no ‘identity-related cognition’ to discover examples of the mathematical issue within climate modelling. Your desire to discuss identity-related cognition’ is a complete red herring. I am surprised that you can be so confident that it isn’t when you have already admitted to not fully understanding what the mathematical issue is.

    To re-iterate: Prominent climate scientists have conceded that an inappropriate branch of mathematics is being used to analyse climate model ensemble uncertainties. I maintain that this could have implications (the same error in other fields has been known to lead to incorrect results) and so it would be better if the appropriate branch were to be used, or at least that the issue should be more widely appreciated. If understanding uncertainty is important, then so should be the correct choice of tools. Please point out the flaw in that reasoning and why the flaw may be due to ‘identity-related cognition’. Or rather don’t – you had your chance on the other thread.


  14. Andy –

    There you go. Although my guess is that you won’t see it either?


  15. Joshua,

    When I raise an issue, I prefer that people talk about that issue rather than challenge that the issue can be taken at face value. These interchanges can only result in me offering you reassurances that are met with dismissive sarcasm.

    Liked by 1 person

  16. John –

    I’m not sure what that means, but based on your previous comment I’m sure there’s no value in further discussion with you.


  17. And just to be clear what I mean by that.

    You have made it clear that (in your view) there’s zero chance that there’s any degree of any well-known cognitive biases in play, in how you apply extremely complex analyses to extremely complex processes related to a domain where you have obviously strong identify-orientarion, despite that you overtly display strong and overlapping identity-related cognition in closely related domains, and thus asking you to reflect on any such potential biases in play is “off-topic.”

    It’s self-sealing and unfalsifiable logic.


  18. >”It’s self-sealing and unfalsifiable logic.”

    Absolutely not. Let me take you through my argument line by line:

    “Prominent climate scientists have conceded that an inappropriate branch of mathematics is being used to analyse climate model ensemble uncertainties.”

    I provided enough quotes for you to see for yourself that this is true. What they are saying about the mathematics is what I already understood to be true prior to any identity-related cognition on my part.

    “I maintain that this could have implications (the same error in other fields has been known to lead to incorrect results)…”

    If you had investigated for yourself, as Ianalexs did, you would know by now that this is also true.

    “…and so it would be better if the appropriate branch were to be used…”

    This is a truism that does not need explaining, unless you think the risk of obtaining incorrect results is acceptable in mathematics that’s used as part of a risk assessment.

    “… or at least that the issue should be more widely appreciated.”

    Why should you think that a wider understanding of the issues would be a bad idea? The fact that there might be something in my identity-related background that leads me to say this wouldn’t make it untrue.

    “If understanding uncertainty is important, then so should be the correct choice of tools.”

    Again, why would this ever be untrue? What is it about my identity-related cognition that would cause me to draw such a conclusion?


  19. > >”It’s self-sealing and unfalsifiable logic.”

    Absolutely not.

    Well, OK then. Glad we cleared up that there’s no self-sealing or unfalsifiable logic.


  20. had to look up “self-sealing” to remind myself when it is used –

    “Definition of self-sealing 1 : capable of being sealed by pressure without the addition of moisture self-sealing envelopes 2 : capable of sealing itself (as after puncture) a self-sealing tire First Known Use of self-sealing”

    so, it seems to mean something else to Joshua –
    this sounds like his meaning –
    “Self-Sealing Arguments Chapter Ten Philosophy 404 Summer 1999”
    a short crappy post (to me), I’ll just quote the last part –

    “Dangers of Self-Sealing Arguments:
    An argument that is self-sealing is vacuous and it is usually offered when trying to shore up a position that is false. One way to avoid the objection of falsity is to make one’s argument impervious to criticism; however, in doing this, you deprive the argument of all content.

    Commitment to self-sealing arguments is antithetical to the type of attitude conducive to critical thinking. To be a good critical thinker, you need to be open-minded and non-dogmatic. Commitment to self-sealing theories and arguments engenders closed-minded dogmatism.”


  21. Cognitive bias, or perhaps more correctly here, confirmation bias, is of course at the heart of controversy over climate change. John and I have agreed that the mainstream “Science Is Settled” paradigm overlooks certain methodological details. The antidote to confirmation bias is to look as far into those details as possible. I’m an academic, and I’ll vouch that pretty much that’s all academia does — look further and further into tinier and tinier details. And when you do, earlier assumptions (heuristics, biases) tend to come out in the wash. Or can do, assuming there’s no strongly enforced paradigm policing ( which unfortunately is the case with Big Climate Science).

    In short, I think Joshua is attempting to tar detailed enquiries with the brush used for sketchy narratives. To say it differently, he’s mistaking (or attempting a fallacy) that scientific method (the ideal enlightenment version, not the morally-policed madrassa version) — is substituting that for casual opinion, which is indeed the province of bias.

    Or an analogy: I wishfully think that I can buy that house. But when I spreadsheet the mortgage repayments against my income, expenses and projections of rate rises, I realise I can’t. Wishful thinking versus exhaustively working out the details.

    So no, studiously zeroing in on an aspect of methodology, such as uncertainty theory, is not blowing off like a methodologically illiterate, confimation-bias-riddled, credulous, Greta-worshipping febrile XR ninny.

    I’ll brace for a word-salad response, with snark dressing on top.


  22. Most of us go for sketchy narratives. 😦 What’s in a word?
    As Humpty says – a question of who’s to be master, that’s all.
    For one side in the AGW debate it’s a call to action using
    fear ‘n guilt messaging, for t’other side, it’s defensive and uses
    irony, – ‘wait a minute… cat-ass-trophe?


  23. Beth: “Most of us go for sketchy narratives.” Ha, that’s true! — not sure about placing irony on the sceptic side though? Isn’t it yet another feature of those invoking “The Science” as a reified, fixed, single-viewpoint authority? Which is to say: that’s not science at all — that’s dogma. And that there is irony.


  24. Ianelexs,

    Science as single -viewpoint authority, that’s ironic. And agree that we can’t just
    allot the ironic vision to one side of the debate.

    Suppose there are two ways to regard irony, I think of literature, Jane Austin
    of the ironic vision and her comic characters being viewed ironically because
    they aren’t aware of something that others think they should be aware of. For
    Jane Austin, the creator, her active irony was appropriate, for participants in
    political debates, as climate change has become, expect comic characters on
    both sides of the argument.


  25. Ian, dfhunter,

    I reiterated my proposition in a comment on 11th October, 2.01pm. If there is any intractable complexity in it, then that can be pointed out. As can any part of the argument that could be influenced unduly by cognitive bias, or any part of that argument that is self-sealing. I would be happy to respond to such a specific critique , but a general challenge that seems to be an argument based upon incredulity and presupposition is too vague for me. As you have said (Ian) ours is an observation regarding methodology that borrows from principles that have already been established far remote from the troubled world of climate science with all its baggage. Understanding how uncertainty works is a means of dealing with cognitive biases and complexity. But first, it helps to get the mathematics right.

    Liked by 2 people

  26. Re: self-sealing and unfalsifiable logic.

    It occurred to me last night that I have offered no concrete evidence that I had first raised the problem of over-interpretation of probability distributions long before I started to do so in the context of climate science. So, I dug out the following extract from a paper I wrote for the SCSC journal back in May 2012 (Volume 21, Number 3):

    “As a result, schooling in statistics has been unjustifiably dominated by the teaching of statistical techniques that take as their starting point the assumption of Gaussian distributions, or similarly computable variability. You may have even been told, like me, that all natural phenomena are prescribed by such distributions. This is a shame, because so much of the uncertainty you have to deal with as a systems safety engineer will have an epistemic basis that has little to do with the Gaussian curve. Furthermore, predicting the safety record of a unique and novel safety-related system cannot, by its very nature, be treated as a frequentist exercise – the problem is that you will.”

    By the same token, predicting the safety resulting from the novel forcing of the climate cannot be treated as a frequentist exercise – the problem is that it is, at least to the extent that the spread of climate model ensemble outputs is treated as a probability distribution curve.

    This is a methodological point I am making. It doesn’t depend in any way upon what I might believe to be the safety of a specific, complex, safety-related system any more than it does upon what I might believe regarding the potential hazards of a complex system such as the Earth’s climate. Whichever domain one chooses, I didn’t have to perform any ‘extremely complex analyses’ to ‘extremely complex processes’ in order to arrive at my conclusion. All I had to do was to reflect upon the inappropriateness of applying frequentist thinking to epistemic uncertainty. That is why I can state with 100% confidence that my assessment of the handling of climate model ensembles has not been biased by identity-related cognition. The only thing that is partisan is that I chose to mention the problem on a sceptic website because I knew it would be of interest to fellow sceptics.

    Liked by 2 people

  27. And it was John.
    thanks for expanding your post/comments.

    ps – Is it only me that can’t get my head around this “self-sealing” quote against John?

    another partial quote from the above link –

    “An argument can be self-sealing in a number of different ways:
    By universal discounting: all possible objections are dismissed, often in ad hoc or arbitrary ways. E.g., conspiracy theories.

    By going upstairs: use of the ad hominem fallacy to dismiss objections; objections are dismissed as a sign that the objector is not yet in a position to understand the argument, or that the objector is actually proving the argument sound by asking those objections. E.g., psychoanalysis.

    By definition: use of the fallacy of equivocation to finesse objections; one makes a substantive claim and then subtly redefines the critical term in a way that guarantees the truth of the claim, even though by doing this the claim is deprived of substance. E.g., selfishness.

    Certain words are also used to seal arguments off: “enough”, “true”, “thoroughly”, etc.”

    as Ian said above – “word-salad”

    thank God I worked in engineering, where we had to get things done.

    Liked by 1 person

  28. Bravo. Nice reply John. Yes, it’s about methodology, nothing more. But sadly we also know that it hits a nerve, or better to say is rather unsettling, so no matter how many millions or billions are funded into The Science™, it’s a verboten topic.

    Liked by 1 person

  29. Ian,

    I think it is to be expected that an assertion that most people have been doing something wrong for decades will be met with resistance. When I brought this subject up with my employer (challenging what the Director of Risk had to say) my concerns were breezily dismissed with ‘well, all of the banks do it this way, so who are you to object?’ That said, when I expressed similar concerns in the company of safety engineering experts, the response was a lot more positive. What I will say, however, is that it is only in the context of the climate change debate that such concerns can be dismissed by reference to ‘identity-related cognition’. Only in the context of the climate change debate will your opponent’s opening stance be to question your ability to exercise good judgement, based upon the company you keep.

    Liked by 2 people

  30. I’ve been digging around some of the papers I collected along the way whilst trying to develop my understanding of how to analyse uncertainty in mathematical models. Here is one of many that point to the fundamental problem when treating model ensemble outputs as a probability distribution:

    “Monte Carlo Simulation in Environmental Risk Assessment–Science, Policy and Legal Issues”


    The two most relevant quotes are:

    “Some researchers, however, have developed techniques for utilizing subjective probabilities to generate probability distributions of risk that incorporate quantitative treatment of model uncertainty. The meaning of probability distributions generated through such methods is problematic, however. Model uncertainty is not a distribution of a natural phenomenon (such as parameter variability), nor is it an uncertainty estimation that converges on a measured value or set of values (like parameter or measurement uncertainty).”

    “In ‘Science and Judgment in Risk Assessment’, the NAS noted the problems with incorporation of subjective assessments of model uncertainty into probability distribution functions, suggesting that such quantitative analyses of model uncertainty be reserved for priority setting and risk trading. For standard setting, residual risk determinations and risk communication, however, the NAS recommended that separate analyses of parameter uncertainty be conducted for each relevant model (rather than a single hybrid distribution), with additional reporting of the subjective probability that each model is correct.”

    This is what I have been trying to get across to Joshua. This is a well-known and documented issue in uncertainty analysis, but it just doesn’t seem to have been taken on board by many climate scientists. There is a fundamental flaw in the way that uncertainty is evaluated in climate model ensembles and you don’t need to take the word of a climate change ‘denier’ to understand this. There is no self-sealing logic on display here and you don’t need to strip away ‘identity-related cognition’ to get to the truth. All you need to do is your homework.

    Liked by 1 person

  31. Once again, boring textbook specialisation holds the key that ought be used instead of the modelling community’s version of p-hacking, which is to stuff subjectivity into parts of the model nobody will ever look at, until you get the answer that feels right. Come to think of it, we need an equally pithy name for the kind of kind of trickery we’ve been talking about here.

    I read on Judith Curry’s blog her review of a celebrated new book by Tim Palmer, that on its cover says it deals with the ‘science of uncertainty’. I’m not likely to buy it much less get around to reading it cover to cover. But John if you do, I’d be curious to know if any of these insights you have thrown up as to uncertainty, come up in Palmer’s book.

    Tim Palmer’s new book has just been published: “The Primacy of Doubt: From Quantum Physics to Climate Change, How the Science of Uncertainty Can Help Us Understand Our Chaotic World”

    Liked by 1 person

  32. Ian,

    From what I can see, it is unlikely that Palmer addresses the issue. If he had, I would expect to see some indication from the book’s contents page or the reviews it has received. Instead, all the talk seems to be about chaos, which is a decidedly aleatory uncertainty. I suspect that Palmer is making the mistake that Gleick and others have made in assuming ‘scientific’ uncertainty has its basis in real world variability and how it is quantified, rather than our understanding of it. As a result there is a good chance that he has not heeded the advice provided by the EPA and NAS regarding the limitations of Monte Carlo. I suppose the only way to find out would be to buy his book. After all, Monte Carlo still has a legitimate role to play.

    Liked by 1 person

  33. >”Come to think of it, we need an equally pithy name for the kind of trickery we’ve been talking about here.”

    Why not? After all, Lewandowsky and his cronies have a name for what we do. They call it a SCAM, which stands for something I can’t be bothered to look up. Basically, it is the assertion that all our talk of epistemic uncertainty and the need to reduce it is just part of the ‘discourse of delay’ funded by Big Oil. Another term used to describe me recently was TWAT, but once again I forget what it stood for.

    Incidentally, I have unearthed another of my past publications that addresses these issues, far removed from the jaundiced glare of the climate change concerned:

    “Reflections on risk and the importance of understanding the nature of uncertainty”, SCSC journal Volume 15, Number 3, May 2006.

    So that would be over 16 years ago.

    Liked by 3 people

  34. John: Palmer’s book happens to appear in I asked a friend (cough) to keyword-search the text for terms of interest. No mention of aleatory, although he has a discussion of epistemic vs ontological uncertainty. But this didn’t go into the concept of incomplete knowledge in modelling. Has a section on Monte Carlo methodology for weather forecasting, and ensemble predictions are discussed more than once. I’m not really advanced enough to spot the assumptions, although from my earlier discussions with you, I expect it’s not a unproblematic as Palmer suggests.

    On the other hand, it’s useful to find good examples of specific gaps in knowledge that are coded into the models, quite apart from critiquing the wonders of modern ensemble prediction (vorsprung durch ensembletechnik?) in which Palmer suggests we can place our fullest confidence.

    One such has appeared on J Curry’s blogsite (there’s a recent flurry of activity there): a translation of an interview with Bjorn Stevens (originally titled “Zu viel Kinderbuch-Wolke”) — Stevens being Director at the Max Planck Institute for Meteorology, specialising in climatic effects of clouds. I peripherally did some work with MPI years ago (different field though), it comes off as a pretty solid and sober institute. The link:

    There’s nothing pithily quotable (though you can piece together his basic contention), and no links to his research papers; but his problem is that within climate models, clouds and their feedback effects are inadequately modelled, hence him calling them “Children’s-book clouds” — not adequately representing the physics of real clouds. In short, he thinks this means the models significantly overestimate temperature rise.

    “According to the simulations, the higher temperatures are mainly caused by a change in the clouds. We consider this effect to be overestimated today.”

    If so, this would be a clear example of epistemic limitations to current models, that cannot be overcome by more of the same Monte Carlo ensemble runs. And also, it suggests that the assertion that ‘the science is settled’ can’t be quite right.

    Liked by 1 person

  35. Ian,

    >”If so, this would be a clear example of epistemic limitations to current models, that cannot be overcome by more of the same Monte Carlo ensemble runs. And also, it suggests that the assertion that ‘the science is settled’ can’t be quite right.”

    Indeed. But as I say, Monte Carlo has a legitimate role to play insofar as it is suitable for modelling aleatory uncertainty. However, once one starts to use it to model the extent to which there is epistemic uncertainty regarding the aleatory uncertainties one will have strayed into modelling the scientific community rather than the physical system they are studying. Only by buying his book will I be able to see whether this error features in any of Palmer’s thinking. He appears to be a brilliant physicist who has pioneered the modelling of chaotic systems so I should not be jumping to any conclusions.

    Incidentally, I see that 2021 Nobel Prize winner, Syukuro Manabe, speaks well of his book. That doesn’t surprise me. My views on the awarding of that prize are to be found here:

    Nobel’s Prize Guys


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