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Matt Ridley Risk Management Failure Deja Vu

Posted on 22 December 2012 by dana1981

Matt Ridley has published another article in a mainstream media source, this time the Wall Street Journal (WSJ), which has a long history of publishing climate contrarian nonsense.  This article is not very different from his previous piece in WIRED magazine, and has already been debunked quite effectively by Climate Progress and Media Matters.  However, there is a very simple explanation as to where Ridley has gone fundamentally wrong; it's the same mistake he made in WIRED and in his professional banking career — Ridley still fails to understand basic risk management and wants to wager the future of the Earth's climate on a flimsy argument.

Ridley Makes a Weak Case

The crux of Ridley's article is that he believes climate sensitivity (the total amount the Earth's surface will warm in response to the increased greenhouse effect, including amplifying and dampening feedbacks) is low.  To support this argument, Ridley references a few studies which find that climate sensitivity is on the lower end of the range of likely values published in the most recent Intergovernmental Panel on Climate Change (IPCC) report, as well as a blog post written by financier Nic Lewis.  We may examine Lewis' argument in a separate blog post, but since it has not been subjected to the peer-review process or published, it is not a very credible or convincing reference.

That's really all there is to it.  Ridley believes that climate sensitivity is low based on a couple of cherrypicked studies (and what his financier friend wrote on some blog), and therefore the planet will not warm too terribly rapidly over the next century, and therefore we have nothing to worry about.

Ridley's Rose-Colored Glasses

Unfortunately if the worst case (or even most likely case) climate scenario comes to fruition, there will be nobody to bail out the planet.

It is certainly possible that climate sensitivity is on the low end of the possible range of values (discussed in more detail below), although we would still have to take serious steps to prevent human greenhouse gas emissions from rising so much that even a low sensitivity scenario would result in extremely dangerous levels of global warming.  However, only considering the best case scenario — which is precisely what Ridley is advocating for in WSJ and WIRED — neglects the scenarios in which climate sensitivity is not low.  If we proceed under the assumption that the best case scenario is true, but it turns out that climate sensitivity is actually not near the lowest possible values, then we will be on a path for catastrophic climate change.

This approach is very similar to the one Ridley took as the non-executive Chairman of Northern Rock, a British bank that, in 2007, was the first in over 150 years to experience a run on its deposits.  The bank had allowed itself to become extremely over-leveraged, with debts more than 50 times its shareholder common equity.  Ultimately Northern Rock was bailed out, borrowing £3 billion from the Bank of England over the span of a few days in 2007.  Ridley was unprepared for the worst case scenario when it came to fruition.  Unfortunately if the worst case (or even most likely case) climate scenario comes to fruition, there will be nobody to bail out the planet.

Ridley Cherrypicking

Knutti and Hegerl (2008) presents a comprehensive overview of our scientific understanding of climate sensitivity.  In their paper, they present a figure which neatly encapsulates how various methods of estimating climate sensitivity examining different time periods have yielded consistent results.  As you can see, the various methodologies are generally consistent with climate sensitivity in the range of 2 to 4.5°C global surface warming resulting in response to a doubling of atmospheric CO2, with a most likely value of 3°C.

Various estimates of climate sensitivity

Figure 1: Distributions and ranges for climate sensitivity from different lines of evidence. The circle indicates the most likely value. The thin colored bars indicate very likely value (more than 90% probability). The thicker colored bars indicate likely values (more than 66% probability). Dashed lines indicate no robust constraint on an upper bound. The IPCC likely range (2 to 4.5°C) is indicated by the vertical light blue bar.

These results include a variety of different approaches, including studies looking at past historical climate changes, recent changes, and climate model simulations.  A project called PALEOSENS recently published a paper in the journal Nature which estimated climate sensitivity based on climate changes over the past 65 million years.  Their results are similar to the range in the Knutti and Hegerl study, as well as the IPCC, with a likely range of 2.2 to 4.8°C global surface warming in response to a doubling of atmospheric CO2. 

Ridley's case is based on a climate sensitivity of even less than 2.2°C, which means that it is a very optimistic and very unlikely scenario.  He has essentially cherrypicked a few studies with the lowest climate sensitivity estimates, and brought in some unvetted blog 'science' by a financeer, while ignoring the vast majority of the body of peer-reviewed climate sensitivity literature.

Ridley Deja Vu All Over Again

Ridley's WSJ piece repeats many of the same mistakes in his WIRED piece — cherrypicking the best case scenario, ignoring the enormous risks if his climate optimism is misplaced, and defending his position with wrong arguments (e.g. claiming that the water vapor feedback is weak, when we know from empirical observational data that water vapor provides a strong amplifying feedback).  The failure to take a prudent risk management approach is also a repeat of Ridley's mistakes in the banking industry.  Reading Ridley's WSJ piece is like deja vu all over again.

Ridley has simply cherrypicked the most convenient scientific papers to support his optimistic view, ignored the vast majority of the scientific literature, and essentially argued that if we are very lucky, we may avoid catastrophic climate change.

It's true that if climate sensitivity is toward the low end of possible values, and if we manage to successfully reduce human greenhouse gas emissions, we may avoid very dangerous climate change.  But what if climate sensitivity isn't on the low end?  It is at least as probable that it could be on the high end of possible values, as a recent study by Fasullo and Trenberth (2012) suggests may be the case.  If we bank (pardon the pun) on Ridley's optimism and it turns out to be unfounded, we will be on a path headed towards catastrophe.  This is a scenario which Ridley consistently refuses to consider, despite the fact that this approach has previously come back to bite him.

A prudent risk management approach involves considering all possible scenarios and preparing for the worst.  The worst case scenario here results in climate catastrophe, and we must try to prevent this scenario from occurring by reducing human greenhouse gas emissions.  Ridley's approach is an ill-advised gamble, and boils down to one simple question — do you feel lucky?  And even if you do, are you willing to gamble with the well-being and security of future generations?

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Comments 1 to 36:

  1. Sort of like playing the lottery...which of course is essentially a tax on people who are bad at math... I don't feel that lucky.
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  2. Darn denialists. We could be having an interesting and educational discussion of how to rightly do a risk analysis -- do you use the mode, the mean, or the entire distribution, weighted by severity of risk? -- but instead we have to go over and over again the dangers of cherry picking for your desired result. I hope for the day when people (especially those active in the media) will self correct when they are tempted to cherry pick.
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  3. Ridley practically ran his bank into the ground. And we're supposed to take his advice on how to run national or global economies with regards to climate? No thanks. Stick a fork in Ridley-as-climate-advisor. He's done.
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  4. Ridley's answer to a question at the parliamentary enquiry to the Northern Rock fiasco was revealing: Q406 Mr Fallon: But you were wrong? Dr Ridley: We were hit by an unexpected and unpredictable concatenation of events. Except that the events were predicted by some analysts. With respect to climate change, just because there are uncertainties does not mean that terrible outcomes are unpredictable or unexpected. Wishful thinking is not an admissible defence against gross negligence.
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    Moderator Response: [DB] Hot-linked URL.
  5. The caption to figure 1 includes this:
    The IPCC likely range (2 to 4.5°C) and most likely value (3°C) are indicated by the vertical grey bar and black line, respectively.
    I could not see either a vertical grey bar or a black line in the image - am I going blind? Perhaps, like Ridley's credibility, they are figaments of the imagination ...
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  6. One of Ridleys arguments that indicates "that the water vapor feedback is weak" is that water vapor does not show any trend. He probably got this piece of misinformation from WUWT. In his guest post at WUWT Forest Mims makes this claim, by citing one sentence from an article on the NASA NVAP global humidity dataset. Had he quoted the entire paragraph, not just one sentence, the message would haven been that the authors did not try to study the water vapor trend. They did not do so because the dataset is currently only suited to study "seasonal to interannual variability" due to inhomogeneities in the dataset. For example, because the types and number of satellites changed during the observation period. But Mims knows better than the authors and does not feel the need to say that the authors of this paper do not agree with his original science without arguments. Furthermore, this dataset is only 23 years long and thus not interesting for trend analysis as the uncertainty would be huge anyway, even if the dataset would not be biased. Another clear piece of misinformation.
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  7. Its funny, but when it came to running a bank, Ridley was an optimist. Everything would be fine. I once heard a lecture on learned optimism. Basically it said that optimists were generally healthier and happier than pessimists, and that we should all learn how to be optimists. However, it did offer a caution. If you are in an aeroplane, and are heading for a thunderstorm, you should very much hope that your pilot is a pessimist. It appears that Ridley has learned little from the failure of his optimism at Northern Rock, and is now applying it to climate science. On a slightly related note, it has been found that the presence or absence of optimism in people diagnosed with cancer does not affect their outcomes. However the presence of hope does lead to more positive outcomes. One hopes it will work for climate change as well.
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  8. It was Sir John Sulston (biologist, Nobel Prize winner) who called Ridley an "irrational optimist".
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  9. Victor @6 Nice write-up on your blog. Perhaps, with your permission, skepticalscience might want to reprint it.
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  10. Several points to make here. I've noticed that most of the 'more sophisticated' sceptics have dropped denial of warming and its anthropogenic origins and now base all their arguments around the climate sensitivity issue. So 'it wont be bad' seems to be the 'meme du jour'. Ridley fits the mould perfectly. To John Brookes: "...optimists... [are] ...generally healthier and happier than pessimists..." They are until overtaken by events they didn't foresee due to their irrational optimism. It's interesting that there are so many optimists around -- I'd have thought that, thanks to evolution, we'd have lost them all to lions hiding behind rocks. The Ridleys of this world (especially given his financial background) tend to fall optimistically into the 'short-termist' camp. It's also a more general failing. I was struck by this graph the other day showing longer timescales than we usually see. If the concern is future generations, rather than our own self-satisfaction, the cherry-pickers need to think a little more deeply.
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  11. I urge you to give Lewis' estimate of climate sensitivity a careful review. Thoughtful commentary has already begun, which suggests that there is merit in subjecting his assumptions to very close scrutiny. If it should turn out that there are assumptions in NL's work which bias its conclusions, then a reference page here would be extremely valuable. My sense is that the more sophisticated contrarians are going to run with this.
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  12. Doug H - That figure has apparently been reformatted/redone to a more horizontal orientation than the original (not certain of its provenance), and I suspect the vertical bar has been lost due to resizing (dropping a few pixels is always risky with thin lines). The full illustration of interest from Knutti and Hegerl 2008 is Figure 3a:
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  13. Re the trend in specific humidity, plots of Dai (2006), HadCRUH (2008) and Barry & Kent (2009) can be found here: HadCRUH data download link here: Tamino looked at this data here:
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    Moderator Response: [TD] Linked the URLs.
  14. This nonsense is so consistent with fake skeptics and those in denial being completely incapable of advancing a internally consistent and coherent hypothesis. The contradiction here is very clear. In the same week fake skeptic and denier web sites have touted two hypotheses that are completely at odds with one another. First, they rehash the long debunked Galactic Cosmic Ray hypothesis. Second, the trot out another favourite that climate sensitivity is low. Well, if GCRs play a big a role as fake skeptics and those in denial claim, then the climate system has to be sensitive to very small forcings, in other words climate sensitivity must be very high, not low.
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  15. BBD @11, Scientists at SkS are looking into the blog article written by financier Lewis. However, like grading/evaluating any bad paper, it takes time to separate the (little) wheat from the copious chaff.
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  16. @ 15 Albatross I'm sorry even to have to suggest this extra workload, especially the *weekend before Christmas*. Unfortunately, it looks as though it needs to be done, and to halt the nonsense, done properly. If it makes anyone feel any better, just consider how much time and effort went into constructing NL's analysis. So very, very carefully.
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  17. If we bank (pardon the pun) on Ridley's optimism and it turns out to be unfounded, we will be on a path headed towards catastrophe. But I'm sure Ridley will be fine. He was born into the 1%. My sense is that the more sophisticated contrarians are going to run with this. Indeed.
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  18. JoeT: "Victor @6 Nice write-up on your blog. Perhaps, with your permission, skepticalscience might want to reprint it." Joe, thank you for your nice words. Everyone has permission to reprint any post. I must honestly say, that I do not see it as a special post. Anyone with access to the literature could have written it. We need more open access publishing to make the life of the climate ostriches more difficult. I am just amazed as the boldness of the climate ostriches and hope that the post helps to speed the demise of this PR circus a little and the word "climate sceptic" will again be reserved for sceptical people. The discussion on the best response to climate change is difficult enough without misinformation.
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  19. BBD and Neven, Fortunately, someone has invested the time to look closer at the curios claims made by Ridley and Lewis. It seems the more "sophisticated" the fake skeptics are, the more skilled they are at deluding themselves and anyone who will listen or take them seriously. A post by ThingsBreak titled "Matt Ridley and the Wall Street Journal misrepresent paper cited in Ridley column" exposes just how "creative" and sly Lewis et al. had to be to force their desired narrative. "Ignoring the two main findings of a paper for values that you’re either estimating from a curve or are creating yourself based on data not used by the paper will be seen by at least some people to be misleading. Claiming that ECS cannot be estimated by paleo data is absurd, especially when so many are aware of efforts like the PALAEOSENS project and various paleoclimatic intercomparison groups." So yet another alleged "nail in the coffin of AGW" is, pardon the pun, vapourized. Water vapour is not our friend in this situation, I'm inclined to call it "Darth Vapour" ;) Physics cares not one iota for the shenanigans of fake skeptics....
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  20. Victor@18 Actually, I read your blog post several days ago. Like you, I had seen the post on WUWT, then I did a google search on NVAP-M which led me to your blog. After I read your post, I went back and read the Colorado State paper. Nice catch on how WUWT (as well as Matt Ridley) distorted the conclusion in the report by quoting a single sentence out of context.
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  21. I really don't understand the likes of Ridley. This year in the UK we started with drought, now we have to much water everywhere and we are no where near seeing the worst of climate change! There are businesses really suffering as well as home owners. The risk is clear in the UK, do nothing and the costs are going to be astonishing.
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  22. John Russell astutely commented:
    "...optimists... [are] ...generally healthier and happier than pessimists..." They are until overtaken by events they didn't foresee due to their irrational optimism. It's interesting that there are so many optimists around -- I'd have thought that, thanks to evolution, we'd have lost them all to lions hiding behind rocks.
    This reminds me of Douglas Adams' observation on the phenomenon, which most people blithely assume is simply a comic instrument:
    The Book: It is important to note that suddenly, and against all probability, a sperm whale had been called into existence, several miles above the surface of an alien planet. And since this is not a naturally tenable position for a whale, this innocent creature had very little time to come to terms with its identity. This is what it thought, as it fell: The Whale: Ahhh! Woooh! What's happening? Who am I? Why am I here? What's my purpose in life? What do I mean by who am I? Okay okay, calm down calm down get a grip now. Ooh, this is an interesting sensation. What is it? Its a sort of tingling in my... well I suppose I better start finding names for things. Lets call it a... tail! Yeah! Tail! And hey, what's this roaring sound, whooshing past what I'm suddenly gonna call my head? Wind! Is that a good name? It'll do. Yeah, this is really exciting. I'm dizzy with anticipation! Or is it the wind? There's an awful lot of that now isn't it? And what's this thing coming toward me very fast? So big and flat and round, it needs a big wide sounding name like 'Ow', 'Ownge', 'Round', 'Ground'! That's it! Ground! Ha! I wonder if it'll be friends with me? Hello, Ground! [Cuts to a distant view as the whale hits the ground and spews up a large mushroom cloud of snow] The Book: Curiously, the only thing that went through the mind of the bowl of petunias, as it fell, was, "Oh no, not again!" Many people have speculated that if we knew exactly *why* the bowl of petunias had thought that we would know a lot more about the nature of the universe than we do now.
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  23. KR @ a2, thank you for posting the graph. The caption makes sense now.
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  24. When I was learning how to fly in the late seventies my instructor put this hood thing on my head so I could only see my instruments or dash and not outside. This exercise was designed to teach a mere beginner like me to never fly in clouds or lose sight of the real horizon or worse at night. He gave me the usual instructions to climb/descend and turn to set headings and various combinations. He then asked me to climb to 7000ft on a heading of 135. I knew there was cloud higher than we were and sure enough we were in thick cloud. I could tell by the sudden dimming of the light. He then put me through a lot of turns climbs and descents and combinations of all these. After about twenty minutes he said 'You do know how to fly on instruments! You were not cheating!' I then told him it was a simple matter to just cross correlate all the instruments to give a true indication of the state of the aircraft. Working in science had given me this insight. Further if you rely only on one instrument and ignore all others you will crash. Even if you look at all and fail to cross correlate and not see the pattern you still crash. The usual control failure is a spiral descent at ever increasing speed into the deck. This is analogous to the deniers flying. They will point to one instrument and say all is good. If that one changes they will find another that tells them all is OK. They then put absolute trust in the balance centre in their ear (natural cycles) . They then ignore that their airspeed is increasing, engine revs are increasing, they are losing height and the artificial horizon looks 'stuck' at some impossible angle. The heading is varying a bit but that is due to the wind! All is fine until you hit the deck at a velocity higher than V never exceed for your aircraft. This chap Ridley has crashed a bank and he now knows how to drive a planet! Bert
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  25. Excellent analogy, Bert@24! The first of such kind that I've seen. I hardly make a post without useful input of mine but this time I make an exception and rest my post just on the applaud to you. Your little debunking analogy is worth exposing and repeating everywhere in popular media.
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  26. Bert #24 It is an excellent analogy. The only difficulty I can see is that you need to have taken flying lessons to really understand the significance.
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  27. The only difficulty I can see is that you need to have taken flying lessons to really understand the significance.
    A bit like the various sciences associated with climate change, in some ways...
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  28. "...although we would still have to take serious steps to prevent human greenhouse gas emissions from rising so much that even a low sensitivity scenario would result in extremely dangerous levels of global warming" I wish this article would've discussed this further (maybe another article?). The deniers conveniently ignore that we're on pace to possibly quadruple atmospheric CO2 levels in the next century, complicated by the potency of methane as we move more towards natural gas, so we're still screwed even with an unlikely low sensitivity.
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  29. @10 John Russell I've only been at the process of combating climate misinformation for a few years now (to which this site has proven indispensable), so other will certainly have seen the transformation you mentioned more than I, but in this time I have noticed the outright denial that warming is occurring start to drop and their arguments have changed. I remember when several deniers in the Canadian blog/news/literature circles I follow were aboard the "greenhouse effect violates the 2nd law of thermodynamics" train. It seems positions such as that have been (more the time being) all but given up for the arguments of low sensitivity or it's not anthropogenic. Slowly but surely, progress is being made. @Bert, I remember going through a similar exercise about 6 years back. Fantastic analogy, I wouldn't have thought to compare the two
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  30. Attacks on the messenger but the message escapes unscathed.  Rightly so becuse he stuck to facts.  Although Ridley is not a botanist his botanical arument was totally correct.

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  31. Hi Roger @30,

    Care to put some detail into that claim? Given all of the nonsense Ridley has spouted in the past, I would be surprised if he got something right, but it's always interesting to hear the argument.

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  32. Leto.

    Ridley's initial claim is that the earth is getting greener and he presented good evidence for that.  Do you wish to dispute that point?


    He also claimed that the increase in atmospheric carbon dioxide contributed to that greening arguing, on correct botanical grounds, that carbon dioxide is plant food.


    Do you wish to dispute that point?  Are there any point in his talk that you would like to dispute?  If so what are they?

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  33. Ferns, cycads, horsetails and the like evolved in palaeozoic times with far higher levels of carbon dioxide in the atmosphere.  Most of the evolution of the angiosperms, at least to generic and family level, had taken place before the end of Jurassic times, also in an atmosphere much richer in carbon dioxide.  The level of carbon dioxide in the atmosphere today is sub-optimal for most plants.  This is of course a fact well known to the operators of commercial greenhouses.  It is no surprise really, and to be expected, that the increase in atmospheric carbon dioxide in recent decades has stimulated plant growth.  Should the inane pleas for reduction in atmospheric carbon dioxide actually succeed plant growth will slow and starvation will become the norm in much of the third world.  Should we be entering a mini ice age, which is a distinct possibility given the lacl of warming for over a decade and the low level of sunspot activity, we might just need all the carbon dioxide we can get into the atmosphere !

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    Moderator Response: [DB] Any further discussion of this line needs to be taken to the CO2 is plant food thread. Off-topic sloganeering struck out. Interested parties may engage Roger Dewhurst on the appropriate threads noted by Doug Hutcheson.
  34. Roger Dewhurst @ 33, your claims seem to be extraordinary and require extraordinary proofs. For a quick review, I recommend having a look at the following articles here:

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    Moderator Response: [DB] Thank you. You pre-empted the need for further Moderator intervention. Interested parties may engage Roger Dewhurst on the appropriate thread.
  35. Hi Roger,

    When I asked for details, I was wondering whether Ridley had mounted any sort of sophisticated botanical argument of relevance to the science of climatology. If you can't answer without mentioning fears of a mini-ice age and mass starvation on the back of "lacl of warming for over a decade", or without dismissing concerns about AGW as "inane", it does give me some idea of the audience he is pitching to, at least.

    Comment policy on this site prevents me from saying much more of what I think, so I'll leave it at that. Some of the more patient folk here at SkS might be ready to discuss your ideas with you.

    I'm not sure you've done Ridley any favours here.


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  36. Roger Dewhurst - your comments are on the wrong thread. See: Ridley, Murdoch and Lomborg Attempt to Greenwash Global Warming.

    Given the prior analyses of satellite greening show opposing trends what is so special about the latest as-yet-unpublished study? See you over at the other thread.

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