While catching up on things this morning, a link at Bishop Hill took me to one of the most penetrating and concise commentaries on the Hockey Stick controversy that I have seen, and it comes from a rather surprising source.
I’m not going to attempt to summarise what it says, mainly because if I did so it would probably give the impression that the author – Sam Norton, a philosopher and country parson – is reiterating arguments that most of us have often heard before, and to some extent this is the case. The power of his post comes not from covering new ground, but from the clarity and rigour with which it brings together issues that are often discussed in isolation: the political influences that contaminate climate science, reliance on arguments from authority, and the insights that applying dispassionate philosophical analysis to a scientific controversy can provide.
If you are commenting here on what Sam has to say then please, please, lets not have yet another discussion of what Michael Mann’s work may or may not tell us about climate over the last millennium. That is not what the article is about. The Hockey Stick saga has far more interesting things to tell us about the relationship between politics, science and belief at the beginning of the 21st century than whether the 1990’s were the warmest decade for a thousand years – if that matters – and that 1998 was the warmest year.
If you consider commenting at Sam Norton’s blog, then I advise you to get all your ducks in a row first. He seems to be a very pleasant and courteous chap, but note his reply to ‘Tess’, third comment down.
Kudos to Andrew Montford (aka Bishop Hill) whose book The Hockey Stick Illusion is helping to bring what appears to be a rather grubby scandal to the attention of a far wider circle of people whose views are valuable.
I just caught the end of another interview with Roger Harrabin on the BBC’s PM programme. It seems that the RS is trying to back pedal somewhat on the story being reported this morning. He said that, in his Reith Lecture shortly, the RS President Lord Rees will choose measured language – specifically referring to “poorly understood feedback”. Harrabin went on to interview Bob Ward (previously responsible for RS public communications) who is far from being an objective commentator. Ward assured Harrabin that all the computer projections were clear: increased GHGs meant the world would get warmer. He agreed there was some uncertainty about the amount of warming, effectively saying that it ranged from dangerous to catastrophic. When Harrabin suggested that some scientists thought warming would be slight, Ward said that, yes, there were such extreme views (at both ends of the spectrum) but the RS, in advising policymakers had to strike a sensible balance – after all, it’s all about risk. And that was it: no contribution from a sceptic of course.
So the Royal Society haven’t changed anything yet but 43 fellows think they should? A quick look on there website tells me that they have over 1400 fellows – so that’s about 3% of the total? I’d expect a few more sceptics than that.
Robin obviously doesn’t read my comments on the politics and psychology of the AGW issue. Unless he was in the business of deliberate misrepresentation he wouldn’t say things like “PeterM would doubtless claim that the 43 Fellows [who] complained that it had oversimplified its messages were obviously evil deniers in the pay of big oil”
Human psychology in this respect is quite predictable – people will argue the case as it best fits their existing world view. For example, a well known Australian Liberal politician argued recently that the Labor government was wrong to accuse the Israelis of forging Australian passports. She said there was “no proof” that they had done it. She sounded quite sincere and probably does believe that to be the case. In a way she is correct, there isn’t any absolute proof but there is certainly a lot of evidence. Maybe she just requires a higher standard of proof than most people? Maybe if she were on a jury she would be arguing for an acquittal when faced with a similar level of evidence. Maybe it’s nothing to do with her being a strong supporter of Israel and she would be saying exactly the same thing if it were the Chinese who were being accused.
I don’t think so. And its the same process with AGW. These 43 fellows, incidentally almost certainly not climate scientists themselves, aren’t immune from a human tendency to decide on issues according to a pre-existing world view. Difficult political implications arise, especially for those of a right-wing viewpoint, with an acceptance of the science of AGW. It’s just so much easier to pretend that AGW is incorrect, or ‘unproven’, and therefore reject it.
Over at RealClimate, I’ve made three on-topic hockey-stick enquiries that were deleted in moderation without any footprint or explanation. The thread was: “What can we learn from the last millennium…?”
My screen copies from that thread follow.
Not wishing to be naughty, but can anyone offer an opinion as to why they were deleted?
Max,
You say “43 Fellows complained that it [the Royal Society] had oversimplified its messages.”
I wonder how many fellows might be thinking just the opposite? That the Royal Society had undersimplified its messages. Especially when they were aimed at ‘cimate sceptics? And even more especially at mid-western American climate sceptics :-) ?
Robin,
Instead of saying there is no “empirical evidence” to support the theory that AGW exists you might want to use the term “attribution”.
There is a timely article, it’s just appeared, on the Realclimate website.
http://www.realclimate.org/index.php/archives/2010/05/on-attribution/#more-2348
You could perhaps give us the benefit of your uninformed opinion afterwards.
Incidentally, if I so have one slight criticism to make about Realclimate, it is that they too tend to undersimplify their arguments. However, I can well understand that, with your great intellect, you may not agree, and will fully comprehend every sentence at the first reading!
BobFJ #103
On the subject of measuring historial temperatures at the tree-line, I’ve got a question which I’d never dare to raise on the specialist blogs. Maybe you or someone else here can answer it.
I understand why tree ring data is collected at the upper limit (in terms of altitude or latitude) of the region where the trees are found, since it’s at the extremity of their survival possibility that tree rings are thought to measure temperature.
But if temperatures change, so will the position of the tree line, so how can you know where the treeline was centuries ago, unless you know what the temperature was centuries ago?
To give a concrete example, a longterm cold spell in the past will have killed off all the trees at the original treeline, leaving none to be sampled in the present, so no record of the cold spell.
So isn’t the reasoning circular (more circular than the average bristlecone pine tree ring, at least)? And doesn’t that explain the millenium-long flat handle of thehockeystick?
PeterM (105):
You say, “Instead of saying there is no “empirical evidence” to support the theory that AGW exists you might want to use the term “attribution””.
No, I wouldn’t: the words have different meanings – and the difference is critical. Thus, if an art expert says that a painting is “attributed” to Leonardo, he means that he is not sure who was the artist, but it might have been Leonardo. Were he sure – from, say, an analysis of the signature or brushwork, documented provenance, etc. (i.e. empirical evidence)- he would have said that it was “by” Leonardo. See the difference?
Nonetheless, I read the RealClimate article with interest. You’re right, it does rather oversimplify the arguments but I suggest that’s acceptable for a blog as opposed to a scientific paper. But, even so, it’s well presented and makes an important contribution to understanding the construction of climate models and the problems associated with their interpretation. So thanks for the reference.
There are two problems about the article however. The first (and least important) is that it’s published on RealClimate which, as many here know from personal experience, can be intolerant of conflicting views (see e.g. Bob_FJ at 103). Therefore, it’s impossible to be sure that the follow-up comments are properly representative of alternative takes on the issues being considered. The second problem is that it’s concerned with computer models.
Now I don’t intend yet again to set out why computer models are no substitute for empirical evidence. Nor should I have to remind you that, in any case, the models used are subject to considerable uncertainty. Only yesterday, we had Roger Harrabin telling the BBC’s Today programme that there was “massive, massive uncertainty” about climate models and Lord Rees (the Royal Society’s President) talking of the “poorly understood feedback” assumptions used for the models. And you might also wish to refer again to IPCC AR4 WG I, chapter 8 (see especially 8.6.3 and 8.6.4) where we learn, for example, that ” … a set of model metrics that might be used to narrow the range of plausible climate change feedbacks and climate sensitivity has yet to be developed.”
So, yes, the RS article is interesting. But, as it’s concerned with attribution and with models, it doesn’t help you a great deal.
Robin,
If you had been ‘paying attention’, you would have noticed that I wrote that Realclimate tended to undersimplify the argument!
Your argument about attribution of paintings is an interesting one, but one which doesn’t really support your case at all. If an expert was 90% confident that a particular painting was ‘largely’ ( at least 90%) the work of Da Vinci, who would have had many apprentices or assistants who would have applied at least some of the paint, how would he call it? If just an ‘attribution’, what level of certainty would he need to be ‘sure’? Don’t tell me 100%! That is just impossible.
PeterM:
Well, I’m pleased you read my post: you’re right, you did say undersimplify. Sorry about that – but I stick by my comment even so. BTW, unlike “oversimplify” which is a commonly used word, “undersimplify” is very unusual. I don’t think I’ve encountered it before. Presumably you meant that the article had been made too complicated – see this. Is that what you meant?
But you’re wrong about “attribution”. Roget’s Thesaurus gives “theory, hypothesis, assumption, conjecture” as synonyms. Er … says it all really: evidence is a different concept entirely.
PeterM:
Hold on – I’ve just read your 104 and see you’ve used “undersimplify” there too! You love that word don’t you? Incidentally, re the 43 RS Fellows (there may well be more who are sceptical – these are merely those who were asked), I see you assume that they are “almost certainly not climate scientists themselves”. Three questions:
1. What’s your basis for making that assumption?
2. Do you consider the views of Fellows who are not “climate scientists” to be of no account?
3. How do you define a “climate scientist”?
BTW, one of the 43 is Sir Alan Rudge, who is an engineer. That’s interesting. In engineering, the standard of evidence required is far higher than would seem to be the case in “climate science”. Even for an engineering project that was unlikely to kill anyone if things went wrong, an engineer would not consider results from unvalidated computer models as an adequate basis for proceeding with a project. Real world testing to verify the model would be expected first. Engineering is a particularly demanding and practical discipline.
PeterM
With all your twisting and turning about the 43 RS fellows who are skeptical of the official political stance of the RS on AGW, I think you missed the part where I predicted that the RS would be unlikely to make any drastic changes, as long as the “big bucks” still support the AGW premise.
So don’t look for any drastic changes.
BTW: 43 fellows who took the effort (and risk) to challenge the society, while over 1,000 did not proves nothing.
Maybe the 1,000+ were cowards, maybe they were lazy, maybe they were not in the “climate” business and felt they were not qualified to comment, maybe they were in the “climate” business and benefiting from a AGW government grant, or maybe they simply did not think of adding their names to the list of challengers.
Who knows?
But I think the safe thing to do is “follow the money trail” for an answer.
Max
Robin
As an engineer, myself, I can fully agree with your assessment.
Scientists involved in basic research often lose touch with reality, while engineers (or applied scientists) cannot afford to do so.
For the computer scientists who are developing and running GCMs, the computer model outputs begin to sound like “absolute truth”, and, of course, the GIGO temptation is also great. Engineers always have to face actual observed reality. This is humbling.
I believe that this may be a reason why many of those who are skeptical of the dangerous AGW premise are engineers (or applied scientists), rather than climatologists, computer modelers or theoretical scientists.
Max
Max,
There is really no difference if you look at the AGW problem from an engineering or scientific perspective. If there were such a position as “Earth Chief Engineer” he would look at rising CO2 levels with some concern and have to make an engineering call on how high and at what rate they should be allowed to rise.
Scotty’s (the engineer) catch phrase from Star Trek was “The engines just won’t take it, Captain”. He was always concerned that the more Gung-Ho members of the crew shouldn’t test the Star Ship to destruction. You wouldn’t hear him say “Sure just do what you like Captain. She’ll be right”.
Robin,
Are you saying that there is no evidence at all that Da Vinci painted the Mona Lisa or the Last Supper” These and other paintings have just been ‘attributed’ to him? You seem to know a bit about this – how is authenticity measured in the artistic world on a scale of 1-10?
PeterM
Again you come with fiction (this time Star Trek).
But to use your fictive analogy: I’m sure that Scotty, once he observed an event like the Copenhagen fiasco, would say:
Max
PeterM
Seriously (leaving Scotty aside), there is a major difference whether one looks at AGW from a purely hypothetical scientific standpoint using theoretical deliberations and modeling techniques to arrive at postulated projections for the future or a more engineering-minded standpoint of insisting on empirical data from actual physical observations (for example to support design calculations).
One skeptic has stated that the “drudge work” of gathering actual data has taken second place to the more exciting “model manipulation” efforts in climate science, and this appears to be true. Physical observations are even cast in doubt or rejected outright when they do not support the theoretical model outputs.
This lack of supporting empirical evidence is one of the key weaknesses of the dangerous AGW postulation, as both Robin and I have pointed out to you repeatedly.
And it may be one of the key reasons that several engineers (and applied scientists) are rationally skeptical of the dangerous AGW premise.
Max
PeterM (114):
What I am saying is that “attribution”, synonymous with “theory, hypothesis, assumption, conjecture”, is an entirely different concept from “evidence”. The latter is needed to verify/validate the former.
Now please answer the three questions I asked you at 110. Thanks.
BTW, Max, my understanding is that the organisers of the request that the RS reconsider its position on AGW only approached these 43. There may well be other Fellows who are equally unhappy about it.
Geoff Chambers Reur 106;
On the subject of measuring historical temperatures at the tree-line etc
I can’t really help much in the can of worms that you open. I suspect that the sampling of tree rings is probably not at the upper limit of the current tree-line, but is more cautious and driven by an assumption that at the latitude/altitudes selected the conditions there (other than temperature) will have remained constant over the millennia. (ho hum). Whilst the recent living tree samples will display an apparently valid chronology, because they have survived say some hundreds of years, the situation for deceased trees that are required to extend the time series may be a bit more sus’. They have to have partly overlapping matching chronology patterns, which I suspect is more of an art to establish, rather than any precise correlation. Bear in mind that no two trees yield identical results. Furthermore, where do the older dead tree samples come from? We know for instance that such well preserved specimens can be found above the current tree-lines, especially in the mountains where snow and ice have receded, but that may not be relevant.
I was amused when back around 2000, Bradley or Hughes, one of those guys from MBH 99 wrote a letter to Nature or Science, (I’ve lost the details), positing that the convergence problem, (hide the decline), was caused by recent prolonged snow seasons reducing summer growth. How silly can you get? These were Manna-Man’s co-authors. They suggested culprit recent extended snow seasons, but not at any time in the past millennia? Sheez!
Of course the silliest part about it, (on top of the regionality problem, if that is not silly enough), is that as far as I’m aware, there is no chlorophyll-photosynthesis growth in tree-rings at nighttime and during the winter. Global average T’s should of course include these rather important temporal periods!
I actually feel that although Mc & Mc did excellent work on debunking the methodology etc of MBH 99, it is so complicated that few people really understand it, and it has become a distraction. It would have been much simpler and understandable to debunk it on issues such as the above, but there is much even more if one cares to look at the basics. Bugger the statistics etc.
Thanks Bob #118
There are a lot of related questions one might ask, and I could no doubt find some of the answers on Wikipaedia. I wondered if anyone else had been thinking about the obvious problems with dendrothermometry, beyond the extremely abstruse statistical shenagigans used by Mann et al, revealed by McIntyre, and explained by Mountford. Your point about growth being limited to summer is a good example. I see points like this mentioned on blogs, but no scientifically respectable criticism. I suspect that there’s a gentlemen’s agreement among dendros not to rock the boat and thus deprive this obscure branch of science of its best client. (Until recently, dendrochronology was used essentially by archaeologists for dating wooden artefacts, I believe).
On Tony N’s original question, I’m not at all sure that the Luther comparison is useful, paticularly as McIntyre clearly hates being labelled as any kind of rebel (he even refuses the label ‘sceptic’). The most interesting point in Norton’s article, I found, was his partial acceptance of the argument from authority, which, though it has no logical validity, is a useful rule of thumb in everyday life: if you know nothing about a subject, ask someone who does.
It’s odd I should find this persuasive, since I’m continually being challenged on global warming threads with questions like “So you think you’re clever than the Royal Society, do you?” To which I answer modestly “In some ways, yes”. I’m uncomfortable with this state of affairs, since my natural tendency is to listen to experts, whether the subject is the origin or the universe or how to grow tomatoes.
The fact that all the scientific societies in the world, plus almost all the political parties, have forfeited their legitimacy on the subject of global warming is to me a source of amazement. When you announce your opposition to the consensus view, the first reaction is often that you’re unbelievably big-headed, and the second that you’re accusing the whole politico-scientific establishment of being part of a conspiracy. The latter accusation is certainly not true.
If a Luther does appear to lead some kind of crusade against global warming, I suspect that he or she will be a social scientist rather than a statistician, since what we need is some indication of how we (scientists, politicians and voters) got into this mess.
A couple of extra pertinent quotes from Star Trek’s Scotty.
On self-defeating complexity (could he have been thinking about computer models??): “The more they overthink the plumbing, the easier it is to stop up the drain.”
And: “A good Engineer is always a wee bit conservative, at least on paper.”
Robin,
You aren’t correct in saying that “attribution” is synonymous with “theory, hypothesis, assumption, conjecture”. Certainly, in the scientific sense, ‘theory’ has quite a different meaning to ‘conjecture’. You don’t get Darwin’s Conjecture of Evolution for instance! Although the Creationists do play on the looser popular meaning of the word ‘theory’ for their own purposes.
Neither are you correct in saying that the usage of the word ‘attribution’ implies a lack of evidence. In this case, the scientific, artistic and popular meanings of the word are synonymous. For example, there may be a certain amount of evidence, which may be more or less conclusive, on both subjective and scientific levels, that a particular work should be attributed to a particular artist. It could range from a mere ‘probably the work of’, which would mean that the chances are just slightly more than 50% to ‘almost certainly the work of’ which would imply close to , but not equal to, 100% certainty.
Its exactly the same in science. The 20th century warming has been attributed to anthropogenic causes to at least a 90% level of certainty.
Alex Cull,
I agree that engineers should be conservative. It doesn’t look good when bridges fall down and, in may case, smoke starts to appear from a PCB!
However, it is curious that the Conservatives (in the political sense) are not being conservative with the atmosphere and climate. Its not them who are saying “You’ve got to hold back on those CO2 and other GHG emissions, Captain! The atmosphere just won’t take it!”
PeterM:
I am wholly correct in saying that “attribution” is synonymous with “theory, hypothesis, assumption, conjecture”. Once again, you are demonstrating an inadequate understanding of the English language. “Synonymous” does not simply mean “the same as”. It means having the same or nearly the same meaning as another word or being closely associated with or suggestive of something. Therefore, the words with which one word is synonymous do not necessarily have exactly the same meaning as each other, as you appear to think from your reference to Darwin.
Nor did I say, “the usage of the word ‘attribution’ implies a lack of evidence”. Read my post again: I said it is “an entirely different concept from “evidence”. The latter is needed to verify/validate the former”. That’s true whether that former be a theory, a hypothesis, an assumption or a conjecture. Thus, although you are right to say that “20th century warming has been attributed to anthropogenic causes to at least a 90% level of certainty”, your problem is that there is insufficient empirical evidence to validate that attribution. And it’s such validation that is required by the Scientific Method.
Get it now?
And PeterM:
Now please answer the three questions I asked you at 110. Thanks.
Regarding the Royal Society, I was amused by the relevance of these observations of William Hazlitt (1778-1830):
Robin,
You now say that there is “insufficient empirical evidence to validate that attribution” whereas before you were claiming a “failure to produce any empirical evidence to support…”
Its a slow process but I do seem to be getting you slightly closer to some sort of logical argument. You aren’t quite there yet though. We can never get to 100% certainty, that is synonymous with proof and, at least, we both agree that science doesn’t work on absolute proofs. So if, as you say, we have enough for the 90% level, how much do we need for ‘validation’?