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« A new dark age? | Main | 'Vermin Supreme', honest, that's his name - Josh 168 »
Saturday
May262012

Myles Allen writes

Myles Allen has asked me to post this response to the thread in which we discussed his Communicate 2011 lecture.

I do think it is sad for democracy that so much energy in the debate on climate change has been expended on pseudo-debates about the science, leaving no room for public debate about the policy response. In the run-up to Copenhagen, public discussion of effective alternatives to a global cap-and-trade regime (which I would personally view with as much scepticism as most of the readers of this blog) was remarkably absent. It still is, and it always will be as long as the public are kept distracted by a debate over the Medieval Warm Period, which has only ever featured in one of the lines of evidence for human influence on climate (and not, in my view, a particularly strong one). The data we primarily rely upon is the instrumental temperature record, which, as I explained in the talk, emerged from the CRU e-mail affair pretty much unscathed (and I stand by the assertion that one would not have got this impression from media coverage of the issue).

My fear is that by keeping the public focussed on irrelevancies, you are excluding them from the discussion of what we should do about climate change should the decade-to-decade global warming trend observed since the 1970s continue and turn out, as current evidence suggests, to be largely caused by the increase in atmospheric greenhouse gas concentrations. Already, I find people arguing that so much has been invested in the emission cap-and-trade approach that it is too late to consider any alternative. In twenty years time, we may find people arguing that it is too late for any alternative to global geo-engineering, which seems even harder to reconcile with democracy. I believe there are effective alternatives that would represent much less of an intrusion into individual lives and the operation of the economy: for example, http://www.nature.com/ngeo/journal/v2/n12/full/ngeo709.html — but they aren't going to happen unless we start talking about them.

To be clear, "good for the planet" in the final line of the talk does not, of course, mean "good for us (or our grandchildren)". That is the whole point. I sincerely hope we do not end up in a situation where governments feel justified in taking highly anti-democratic measures to stabilise global temperatures, however effective they might be. I still believe this is a problem we can solve without compromising fundamental democratic principles, but the longer we leave off talking seriously about it, the harder this will be.

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Reader Comments (250)

Myles has tied up 35,000 computers running his models (which presumably like other climate models cannot actually be tested - I therefore suspect that the whole exercise is simply PR).

Anyway, let's guesstimate those machines consume 100 watts each. So Myles Allen is burning 35,000*100 = 3.5 megawatts - day in day out.

How many tons of CO2 has Myles personally put into the atmosphere? Let's take 0.5kg per kWhr - so Myles is running at 3.5 x 10^6 x24 x 356 x 0.5 = ~15x10^9 kg = ~15x10^6 tons per year. So 15 million tons a year.

If Myles were concerned about CO2 and the planet - he would be asking people to turn their computers off when they aren't using them.

May 26, 2012 at 11:14 PM | Unregistered CommenterZT

Kudos to Myles Allen for engaging here, I'm impressed that he is willing to take the time and effort to do so.

I remain confused by this position though, and I see others above have made similar points:

the instrumental temperature record is indeed the main data we rely on in support of the claim that most of the warming observed over the past 50 years is likely to have been caused by the increase in greenhouse gas concentrations.

This is a contentious point - maybe not amongst the narrow viewpoint presented by the IPCC, but as Cohn and Lins rightly pointed out way back in 2005, we don't know the the correct mathematical description of natural variability without CO2 emissions, which prevents us from forming a reliable null hypothesis; furthermore, entirely reasonable forms of the null hypothesis result in a failure to reject natural variability as the cause of the recent warming even at the weakest confidence level commonly used in scientific papers (95%).

Why is this relevant? Because the climate during medieval times helps us to better understand "natural" variability, which allows us to home in on a meaningful and reliable null hypothesis for natural variability. However, to my knowledge, everyone who has published in the literature on the topic (including many mainstream climate scientists, e.g. Hans von Storch) has found natural variability to be one of the types yielding the broadest CIs from Cohn and Lins' paper. As we see, understanding the MWP (amongst other things) is pivotal to the interpretation of the instrumental record since it forms part of the null hypothesis of "no significant change".

The IPCC disgracefully swept this published viewpoint under the carpet after the second order draft for AR4, I hope the IPCC is more willing to listen to thoughtful, credible counter points to the narrow consensus view (which is far from the only perspective published in the scientific literature).

May 27, 2012 at 12:32 AM | Unregistered CommenterSpence_UK

Dr Myles Allen, you say "the solution is perfectly simple. Anyone who extracts fossil carbon out of the ground should be obliged to put a fraction of that carbon back underground in the form of "sequestered" (buried) CO2."
And your Physics department says "Estimated cumulative emissions from fossil fuel use, cement production and land-use change since industrialization began are 557,768,000,000 tonnes of carbon"

According to my calculations, if you manage to sequester that amount of carbon as CO2, you will be sequestering 1,486,000,000,000 tonnes of oxygen as well. That sounds very bad.

Dr Allen, please tell us what fraction of carbon should be sequestered, and how you propose doing that, and what will that cost, and how much energy will be used while doing that? What percentage of the 557,768,000,000 tonnes of carbon will be sequestered and will be the fall in temperature if you succeed with your plan?

May 27, 2012 at 12:45 AM | Unregistered Commenterjaymam

May 27, 2012 at 12:45 AM | jaymam
Dr Myles Allen, you say "the solution is perfectly simple. [ ... ]
----------------------------------------------------------------

Indeed, the solution IS perfectly simple ... cut out the rubbish and present the data, the methodologies, and above all be honest and frank in discussion. Some advice to Myles Allen from Edward Cook:

date: Wed, 3 Sep 2003 08:32:11 -0400
from: Edward Cook
subject: An idea to pass by you
to: Keith Briffa

" ... Publish, retire, and don’t leave a forwarding address Without trying to prejudice this work, but also because of what I almost think I know to be the case, the results of this study will show that we can probably say a fair bit about 100 year variability was like with any certainty (i.e. we know with certainty that we know fuck-all)."

May 27, 2012 at 1:48 AM | Unregistered CommenterStreetcred

Dr. Myles Allen expounds:

I do think it is sad for democracy that so much energy in the debate on climate change has been expended on pseudo-debates about the science, leaving no room for public debate about the policy response.[...]

[and]

My fear is that by keeping the public focussed on irrelevancies, you are excluding them from the discussion of what we should do about climate change [...]

Frankly, I think it is far sadder for democracy that one who calls himself a scientist should so arrogantly presume that appealing to his own authority (and/or the "expert judgment" of his fellow IPCC authors) is an argument that the public should unquestioningly accept.

Dr. Allen seems to have adopted the approach urged by the "sustainability communications" company, futerra:

Forget the climate change detractors

Those who deny climate change science are irritating, but unimportant. The argument is not about if we should deal with climate change, but how we should deal with climate change.

But let's set aside the rather meaningless phrasing (e.g. "climate change detractors" and "those who deny climate change science") used solely for the purpose of denigrating and dismissing any who have the temerity to question the validity of their claims.

Was Dr. Allen not paying attention to the words of Joseph Alcamo (who, along with Mike Hulme, has the distinction of being a former consensus coordinator par excellence) when he addressed the IPCC at Bali on October 26, 2009:

as policymakers and the public begin to grasp the multi-billion dollar price tag for mitigating and adapting to climate change, we should expect a sharper questioning of the science behind climate policy

I've often wondered what it is about "multi-billion dollar price tag" that climate scientists seem to have such difficulty understanding.

But speaking of "sustainability" ... since even the UN's Secretary-General has "moved on" from "climate change" as the 'greatest threat to the future of the planet' [in fact he doesn't even mention "climate change" in a May 23 Op Ed] ... if Dr. Allen's assertions to the effect that the 'non-pseudo debates' and 'relevancies' have been resolved are correct (along with his "perfectly simple solution"), perhaps - as an IPCC insider - he could explain why the world has any need whatsoever for AR5.

May 27, 2012 at 2:15 AM | Registered CommenterHilary Ostrov

I just came across this article (via WUWT) from Dr Clive Best concerning evidence for negative water feedback from CRUTEM4 data...
http://clivebest.com/blog/?p=3659
...and thought it was quite relevant to this thread.

Clearly it isn't (yet?) published as a 'peer review' paper, but it does indicate a way in which the empirical evidence can be interpreted to suggest that the CAGW hypothesis may be flawed.

Given his initial comments to Philip Bratby (May 26, 2012 at 9:06 AM), I'd be very interested to hear Professor Allen's thoughts on this... and maybe those of Dr Betts, too.

May 27, 2012 at 3:44 AM | Unregistered CommenterDave Salt

It is important to understand that we use physics, and not just correlations of timeseries, in quantifying the greenhouse contribution. The instrumental record does not support a 1K climate sensitivity (the IceMan comment) -- it might be just consistent with a 1K sensitivity, but that would be right at the low end of a very generous uncertainty range that would also encompass much higher values. Most likely estimates come out between 2 and 3K.

May 26, 2012 at 9:06 AM | Myles Allen>>>>>>

"Uncertainty range" - "Most likely estimates"

Now we're getting into some REAL science we can convince the politicians [who pay for our research grants] to pour ever more £trillions into our "Most likely estimates"

Sorry chum, I really don't care how you choose to describe your scientific credentials, You'll get no deference from this non 'climate scientist' - if there actually is such an official scientific degree!

May 27, 2012 at 4:18 AM | Unregistered CommenterRKS

What we have is a confused picture of potential, theoretical effects that cloud the issue. Let's rewind, my null, and dare I suggest what should be everyone's null, is that man-made CO2 is not causing any meaningful GW. The temperature record is flawed, it has been tinkered with and that together with UHI effects make it essentially worthless. Even if one were to hang ones hat on what looks like a biased view of longitudinal trends and ignore the obvious data processing chicanery, it means very little unless one has observed trends that correlate to the corresponding alternative hypothesis to the almighty null.

Modelling worthless data is a worthless exercise no matter how much computer power one throws at it. The only conclusion to this experiment, no data just theories, is that we cannot reject the null, try harder.

May 27, 2012 at 4:32 AM | Unregistered CommenterDavidCH

Here's what climate scientists like Myles Allen and Rob Wilson (the latter also commented dismissively on BH about the ongoing significance of the "Hockey Stick" reconstructions) need to address effectively to recoup credibility for the "science communications" of climate scientists: it is not the critics and skeptics but the IPCC and its acolytes who have made the "Hockey Stick" reconstructions central to the public debate.

Steve McIntyre on the IPCC's trumpeting of the Hockey Stick


"But it’s not Bishop Hill that Myles Allen should be criticizing; it’s John Houghton who more or less made the Hockey Stick the logo of the IPCC. Mann was told that IPCC higher-ups wanted a visual that didn’t “dilute the message” and they got one: they deleted the last part of the Briffa reconstruction – Hide the Decline. If, as Allen now says, it’s an “irrelevancy”, then Houghton and IPCC should not have used it so prominently. And they should not have encouraged or condoned sharp practice like Hide the Decline." [Steve McIntyre]

===================================================================

ME: I do not see how one can with consistency take the positions Myles Allen and Rob Wilson have taken here wrt to the "Hockey Stick" graph(s) and not severely criticize the IPCC and then Al Gore for the way in which this graph was made an icon of the CAGW case. The public has in effect been told that this graph and supposed reconstruction evidence are of enormous, compelling importance driving decisions about countless billions and trillions of dollars worth of resources. The use to which this graph has been put by the IPCC and Al Gore (and in effect the Nobel Peace Prize committee) now implies that this a (the) central issue in public understanding of "climate change" to date. The scientists may believe they have different and better evidence, but the "science communications" aspect is that millions of people and countless policy makers have been sold the Hockey Stick.

May 27, 2012 at 4:36 AM | Registered CommenterSkiphil

This 'settled' climate science seem quite complicated to me and obviously deserves the well paid attention of those who'd be otherwise unemployed.

From what I can gather it seems that, at great public expanse, many thousand of [subsequently doctored] temperature measurements are taken at carefully selected sites, mainly in the northern hemisphere, in order to somehow PROVE a hypothesis [based on a century old experiment with some CO2 enclosed in a glass bottle] to be used as a predetermined political argument centred upon a new world order, originally mooted by the Club of Rome and later rolled out under the aegis of the UN.

Is this how climate 'science' works or have I missed something?

May 27, 2012 at 4:57 AM | Unregistered CommenterRKS

I am completely gobsmacked. What is the relevance of the instrumental temperature record ? Since when does the fact that global temperatures are either going up or going down have anything to do with energy policy ?

The climate is always changing .. its like the stock market - its either getting warmer or colder .... that's not the issue. The issue is whether or not the current upward trend (over the last century) has anything to do with CO2 emissions. And on that score the EVIDENCE is remarkably THIN !

May 27, 2012 at 5:31 AM | Unregistered CommenterImranCan

From the Ecclesiastical Uncle, an old retired bureaucrat in a field only remotely related to climate with minimal qualifications and only half a mind.

Professor.

1. I did admire the skills you deployed in your presentation – as good as an actor’s. In this member of your audience, you induced an immediate emotional response: well good, very eloquent and convincing and so on. But as is the way after such experiences, on later reflection I found that my appreciation was more of the messenger than of the message

However, it is clear you richly deserve your appointment as a professor – you have the rhetorical skills to profess anything.

2. You are sad for democreacy …

Yes, a very natural reaction from someone who has so toiled diligently, but nevertheless failed.

If is any comfort, I offer the opinion that your mission was impossible and the failure inevitable. I am tempted to advise you to turn to some other less daunting task but realize practical considerations over sources of funding may restrict your ability to do so.

Dr Betts.

I was interested that you directed the interested to an IPCC source.

The cognoscenti here.

I am surprised that in scorning Dr Betts’ source, criticism seems to have been confined to technicalities. In this instance, would not the addition of an hominem attack truly aid the case? (Hominem is the wrong word, of course: what’s the Latin for organization?)

As with employment of the UAE, the IPCC was created to clothe governments’ espousal of the green religion with science. With respect to the IPCC, this has, I believe, been documented by people I find convincing and I find it easy to infer the same of the employment of the UAE from leaked/hacked correspondence and so on.

Overtly, the purpose of both was/is to investigate climate science. Covertly, they were to come up with findings that endorsed adherence to the faith and their work is conducted in accordance with this requirement.

Why do people not routinely point out that this or that statement by either body is yet one more in a series directed at advancing the covert purpose ? By confining objections to technicalities, the objectors appear to endorse the overt purpose notwithstanding its subsidiary status.

Exposure of the covert purpose would do much to reduce the impact of these organizations’ statement and should be routine.

May 27, 2012 at 6:39 AM | Unregistered CommenterEcclesiastical Uncle

I too would like thank Dr Allen for running the gauntlet of posting here and for taking the trouble to respond to occasionally provocative comments. I too am puzzled as to why he appears to think that the nature and scale of the MWP is irrelevant to the climate debate. Why then in his opinion was the hockey stick given such prominence in the IPCC Climate Change 2001 WG1 report? Many of us who have a professional involvement in environmental science, or who have simply looked at some of the literature, are aware that change on a variety of timescales is and always has been a feature of the earth's climate. Whatever we do about current energy policy will not change that fact. Sure, as Dr R Pielke Snr has pointed out in a long list of academic publications, multifarious human activities have long contributed to this natural melting pot of climate change; adding to the atmospheric store of CO2 is just one such human activity. I am not aware of any observational evidence that can distinguish a measurable role for anthropogenic CO2 levels in recent climate fluctuations. But perhaps Dr Allen can enlighten us?

May 27, 2012 at 8:06 AM | Unregistered CommenterColdish

I appreciate that people who have devoted a lot of time to the analysis of paleoclimate data find it irritating when scientists who don't work in that area dismiss it as uninformative. That was a talk to journalists who I felt (and still do) got the UEA e-mail affair out of proportion. I did not mean to belittle the efforts of Steve McIntyre and other paleoclimate scientists to reconstruct the pre-instrumental period: if they were able to produce reliable reconstructions of global temperatures over the past millennium, and associated forcings, that would indeed be a very valuable resource. But I think we need to be honest that they aren't there yet, and hence very few papers outside the paleoclimate niche make use of tree-ring data, whereas we all use the instrumental temperature record all the time.

Apropos Steve's remarks about the IPCC, the only attribution statement in the IPCC Third Assessment Summary that made reference to the MBH reconstruction was "Reconstructions of climate data for the past 1,000 years (Figure 1b) also indicate that this warming was unusual and is unlikely to be entirely natural in origin." This is a very cautious statement ("likely" means a 1-in-3 chance that the warming is entirely natural in origin), reflecting our caution at the time about these new pre-instrumental reconstructions.

The key evidence provided for the headline attribution statement "Most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" was the comparison of model simulations forced with and without anthropogenic drivers with the instrumental temperature record.

Myles Allen

May 27, 2012 at 8:14 AM | Unregistered CommenterMyles Allen

Fifty years is nothing. If you have that, can I claim the last fifteen years are significant? No, I can't, because it is not long enough. The effort to belittle the importance given to the hockey stick is blatant and disingenuous. You know it and we all know it. If there was an MWP then climate science is not in a position to say anything for sure about natural variation.

Anyway, only an idiot would be wasting a beautiful Sunday mornig at 8:14 posting to a blog...ooops.

May 27, 2012 at 8:36 AM | Unregistered CommenterRhoda

Professor Allen.

May I state at the outset that I have no qualification whatsoever in climate science or even a vaguely related field.

I am, however, scientifically trained at a post-graduate level and am therefore somewhat capable of understanding elements of a scientific argument.

There was a time when I fully accepted the climate debate from an AGW perspective to the point of not owning a vehicle for 5 years and paying a voluntary levy on my power bills so would hope not to be accused of not having a degree of principle in the matter.

I would have some regard for you voluntarily walking into the lions den in the above manner in the way you have as it does show a certain strength of character so fair play to you there.

However (ah, the 'however') would you feel safe enough to comment on both on the complete hypocrisy (with respect to consumption) of some of the more vocal 'communicators' of the science (need I say the names?) and what, to my mind, are some rather suspect predictions made on the back of of this modeled science?

As prompts I refer to total cyclone energy, a clear confounding of ice coverage prediction (on the back of NSIDC data) and as an aside I really must mention the poor polar bears who have done nothing but burgeon it seems....I may be wrong....

As an ignoramus in this field (honest) I am now at the point where I will start believing there is a crisis when the people who tell me there's a crisis start acting like there's a crisis....

This fair of me?.

May 27, 2012 at 8:37 AM | Unregistered CommenterThomason

"I did not mean to belittle the efforts of Steve McIntyre and other paleoclimate scientists to reconstruct the pre-instrumental period: if they were able to produce reliable reconstructions of global temperatures over the past millennium, and associated forcings, that would indeed be a very valuable resource. But I think we need to be honest that they aren't there yet"

Once again Professor Allen stoops to playing the Jedi Master "these are not the droids you are looking for" mind trick.

Steve Mcintyre is/was NOT "attempting to reconstruct the pre-instrumental (temperature) period": he very successfully showed that Mann's hokey-schtick reconstruction was a load of crock.

Mann's graph borders on scientific fraud, as anyone who had ever even heard of the MWP or LIA could ascertain at a glance. Nonetheless, the IPCC continued to use it as their "poster child" for years until Mcintyre's efforts finally saw it consigned to the level of disdain it now so rightfully deserves.

Yet even today "climate scientists" (and I use the term "scientist" generously) continue to defend it and its use, or at best, simply try to pretend the whole episode never happened - which seems to be your preferred tactic.

And you wonder why a large - and growing - proportion of the population consider "climate science" as a very bad, and expensive joke, and its practitioners - such as yourself - as the modern-day equivalent of fire-and-brimstone preachers from obscure Fundamentalist cults.

May 27, 2012 at 8:57 AM | Unregistered Commentermemoryvault

Why are we not using the thermometer records of the years 1910 to 1950? Are we certain we can explain that variability and the rate of increase? Those are good records. I do not see why any scientist would omit them from consideration, unless he was trying to improve his case.

May 27, 2012 at 9:14 AM | Unregistered CommenterRhoda

Myles @ 8:14 AM,

Thank you for the very clear points you have made here.

In particular, you mentioned that "The key evidence [for attribution] was the comparison of model simulations forced with and without anthropogenic drivers with the instrumental temperature record."

This is certainly my understanding of the position too, and I think many sceptics would except it as well. It is also a point of criticism as well. For example, estimates of 20th century solar forcing have been the subject of debate in the literature since AR4 and the consensus (such as it is) has moved significantly. You may find some discussion of this, with Richard Betts and references, here.

I also understand that you may want to de-emphasise the importance of reconstructions, but I point out to you that the modern ones do show similar variability to the instrumental record. On the other hand, the variability seen in the models used for comparison does not match well with either the instrumental record or the reconstructions, once you look beyond time-scales of a few decades. Beyond such time-scales, model simulations show similar variability to MBH.

Again, my suggestion is that to make your arguments more convincing, it would be a better strategy to address the question of natural variability head on, and to thereby demonstrate clearly why the sceptics are wrong about it.

May 27, 2012 at 9:17 AM | Registered CommenterPhilip Richens

This is simply pythonesque. How can you possibly engage with someone who insists we stop discussing the NEED for a policy in order that we dan get on and agree and implement one.

As an intelligent voter of independent mind, I will not agree to end discussion of the science until it can establish that need.

And here is some free advice that Mr Allen may communicate. If, as an academic, it is some form of trust he seeks from me, he would be helped along by a much greater commitment to honesty and openness. Maybe start with a frank admission of the wide range of general and specific (the true extent and fraudulent nature of hide the decline say, as revealed in climategate).


So why it start with that? You want to engage? You want to know what it will take for skeptics to simply get on board?

Start on this forum with an unconditional admission that:

You were either completely wrong in that video or you were lying. The sum of the implication of climategate were far far large and more serious than you claim.
Why, the irony is that you host here wrote an entire book on it and you are here defending claims that he expended his energies on nothing more that "0.02 degrees in the 1800s".

May 27, 2012 at 9:27 AM | Unregistered CommenterGeckko

One or two posters have mentioned the alleged fiddling of the historical temperature record. For the benefit of any neutral observers of this debate, here's an indication of the skulduggery: http://endisnighnot.blogspot.co.uk/2012/03/giss-strange-anomalies.html

If there's a legitimate reason for knocking 0.9C off the early 20th century and upping the later figures by 0.8C I'll be happy to delete the 'strange anomalies' page. What do you reckon, Myles: is this (a) a legitimate sanitisation of error-strewn historical records or (b) a cynical corruption of the record in order to create a spurious warming trend and careers built upon it?

May 27, 2012 at 9:47 AM | Unregistered CommenterBrent Hargreaves

" ... should the decade-to-decade global warming trend observed since the 1970s continue and turn out, as current evidence suggests, to be largely caused by the increase in atmospheric greenhouse gas concentrations."


Percentage of CO2 in atmosphere: 0.038%
Percentage man-made: 3%
3% of 0.038 = 0.00114 of one per cent
Political target: 20% reduction
20% of 0.00114 = 0.0002279999999 of one per cent

So, re the policy implications, I'm sorry but I still cannot see why we should hobble our industry and accept prohibitively expensive, intermittent, and possibly rationed energy *only in the west*, which will hit the poor and the elderly hardest, on the basis of a few people obssessing about controlling 0.000227999999% of a trace gas with debated sensitivity.

May 27, 2012 at 10:22 AM | Unregistered CommenterBarbara

Long on Bull, short on Science.
Welcome to the World of Myles Allen and Climate "Science".

May 27, 2012 at 11:21 AM | Unregistered CommenterDon Keiller

Apologies, my hyperlink got mangled above and now goes to an older CA article on a different topic, I don't know how that happened. Let's try again, this is for the new Steve McIntyre article discussing aspects of this thread, the IPCC, and Climategate:


Corrected hyperlink to Climate Audit post on Myles Allen and Bishop Hill discussion

May 27, 2012 at 12:40 PM | Registered CommenterSkiphil

RE: Myles Allen says:

"I did not mean to belittle the efforts of Steve McIntyre and other paleoclimate scientists to reconstruct the pre-instrumental period: if they were able to produce reliable reconstructions of global temperatures over the past millennium, and associated forcings, that would indeed be a very valuable resource."

You are really not listening to the arguments. Out of many points about work by Steve McIntyre and others, the following are so very simple to understand, yet SO important:

1. Manns Hockey Stick calculation fails on R^2 validation. In other words it has no statistical significance. I believe McIntyre and others take the view that any attempt to reconstruct paleoclimate from tree rings is futile and this is the reason they do not offer an alternative "reconstruction".
2. Hide the decline. The post 1960's decline of tree ring data means that in the modern warm period tree rings appear to be inversely correlated with temperature, whereas in the paleo reconstruction they are assumed to be positively correlated. Which is it? Or is it both? If the latter then the tree ring response curve is multivalued and attempts to use it to reconstruct paleo climate are pointless.

Myles Allen, this is undergraduate science yet you seem not to be able to grasp such arguments as to why the paleoclimate reconstructions on are offer so suspect. The IPCC and John Houghton invested vast propaganda value in these and yet when it is pointed out that they are useless at best (and deliberately misleading at worst in the case of Yamal and "Hide the Decline", your response is push the responsibility back onto those who pointed out the results presented were invalid.

Mann's papers, Briffas papers, Steig09 should all be withdrawn. They are propaganda masquerading as science and they have no merit in the debate on climate change.

May 27, 2012 at 12:54 PM | Unregistered CommenterThinkingScientist

The 'hockey stick' debate does not seem like an '"irrelevancy" to me. It is critical to the definition of a null hypothesis. That is precisely why it was created for the IPCC. It may seem irrelevant to those who do not wish to discuss the science.

Be that as it may, when, as invited, I look at a satellite instrumental record dating back to it's start in the 1970's, I just don't see the justification for concern.
http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_April_2012.png

May 27, 2012 at 1:23 PM | Unregistered Commentermichael hart

Myles Allen does have a point; it is useful to discuss how we might deal with the warming world and/or cooling UK.
It’s a pity that the article he linked to appears to be pay walled. Nevertheless we can go through the necessary steps:
Step 1 we have to decide if we are going to try to stop it; is there an environmental, economic or scientific imperative? This where the MWP and LIA come in, for it appears that we and all the life around us has been through worse before and that cold is more evil than hot.
Economically it would be beneficial to completely ignore it: we are a technologically advanced kingdom, we ought to be able to adapt faster than others, so in this devil take the hindmost world that should give us and our grandchildren an advantage, one which we surely need if we are to overcome the UK’s parasitic burden. Maybe we should pay to remove the sulphur scrubbers from the coal fired power stations to cool things down a bit, for others.
Is there a scientific imperative? Well we have ‘been here before’: the science behind genes and evolution is very strong, yet when the eugenics movement (publicly funded at UCL and Liverpool University as I understand it) urged the sterilisation of yobs and the mentally defective, we as a nation shrugged our shoulders and decided against it. Myles must be aware that in another universe he is presenting computer simulations of the impact of allowing the underclass to breed uncontrollably. There is no such thing as a scientific imperative.

There is no need to go any further, really.

May 27, 2012 at 3:02 PM | Unregistered CommenterC

Simple layman being here. We are constantly told that the process of fracking is fraught with dangers. In that case, why is is that carbon sequestration in the form of inserting co2 into the earth, is not?

May 27, 2012 at 3:03 PM | Unregistered CommenterJeremy Poynton

"This is simply pythonesque. How can you possibly engage with someone who insists we stop discussing the NEED for a policy in order that we dan get on and agree and implement one."

Thank you. Much less energy would have been expended had Allen precised his statement as follows

"Nothing to see here. Move along now".

Which is what it amounted to.

May 27, 2012 at 3:08 PM | Unregistered CommenterJeremy Poynton

I'd just like to ask Professor Myles Allen a couple of questions: "Did you read 'The Hockey Stick Illusion'?" - and: "If you have read it, did you understand it?"

May 27, 2012 at 3:42 PM | Unregistered CommenterJimmy Haigh

I'd like to ask him a lot of questions, but there you are. I will settle for one. Do you disavow the cheats?

You see, one won't do. Do you admit that some scientists have not followed good practice for whatever reason or motivation? Do you disavow their work? Do you agree that when their errors were pointed out , that was the time to come clean and correct the record, not to defend bad results? Do you disavow those actions?

May 27, 2012 at 3:53 PM | Unregistered CommenterRhoda

Dr Allen: nice to see that you were online and hard at work online at breakfast time on a bright Sunday morning!

You wrote: "I did not mean to belittle the efforts of Steve McIntyre and other paleoclimate scientists to reconstruct the pre-instrumental period: if they were able to produce reliable reconstructions of global temperatures over the past millennium, and associated forcings, that would indeed be a very valuable resource. But I think we need to be honest that they aren't there yet..."
My understanding is that Steve McIntyre has made it clear that he is not trying and has never tried to 'produce a reliable reconstruction of global temperature over the last millennium'. There are others with more specialised skills who can take on that task. However what he has done to demonstrate that some of the most frequently cited 'reconstructions' are suspect on at least 2 grounds: (i) their excessive reliance on a small number of anomalous tree rings from restricted geographical areas near the tree line and (ii) their foolhardy lack of skill with some basic statistical procedures.

Following (and perhaps in response to) my comment that "I am not aware of any observational evidence that can distinguish a measurable role for anthropogenic CO2 levels in recent climate fluctuations",
you wrote: "The key evidence provided for the headline attribution statement "Most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" was the comparison of model simulations forced with and without anthropogenic drivers with the instrumental temperature record." Well, thank you for commenting, but model simulations are not observational evidence. Until they can be tested against reality they are just speculative. So I'm still unaware of "...any observational evidence that can distinguish a measurable role for anthropogenic CO2 in recent climate fluctuations."

Regards, Coldish
(Apologies for using a pseudonym: I do academic consultancy work for the science faculty of a UK university and I would prefer my employers not to know that I ask questions about climate.)

May 27, 2012 at 3:53 PM | Unregistered CommenterColdish

Dr. Allen's last paragraph reads like a threat to me.

His trust in the science,which is characterized by his use of the phrase ". . . as current evidence suggests . . " while admirable, is, to use a well-worn term in this debate, alarming. "Current evidence" in science has frequently given rise to false theories down through the ages, and I would suggest to Dr. Allen that the "current evidence" for CAGW is now being superseded or coming under attack from many quarters and justifiably so.

I challenge Dr. Allen and others like him to provide a list of 10 seminal (the term "canonical" has also been used) peer-reviewed papers that provide the conclusive evidence that catastrophic climate change is imminent unless energetic action is taken to mitigate it. My understanding is that the temperature record of the past 12 years or so is refuting the narrative of CAGW as it has been presented over the past two decades, most notably by people like Al Gore, who don't have the slightest idea what they are talking about.

If there are papers that explain the apparent pause in warming, or can guarantee we are not entering into a period of global cooling, I'd like to see them. Many learned people believe or are investigating the hypothesis that we are entering a cooling period.

A comprehensive list of proofs, rather than constant reliance on "the science says such and such and is irrefutable" would be helpful for those of us whose skepticism is increasing on a daily basis. A list of the ten most influential peer-reviewed papers would be helpful in providing a solid foundation for the claims of those who believe catastrophic climate change is imminent.

May 27, 2012 at 3:58 PM | Unregistered Commentertheduke

Allen is suggesting that if democracy goes, it will be the fault of us few thousand climate sceptics. He says

I do think it is sad for democracy that so much energy in the debate on climate change has been expended on pseudo-debates about the science
and
the public are kept distracted by a debate over the Medieval Warm Period..
and he ends
I still believe this is a problem we can solve without compromising fundamental democratic principles, but the longer we leave off talking seriously about it, the harder this will be.
So it is supposedly we sceptics, with our irrational desire to discuss the science, who are delaying the serious talking about what to do about the problem, and thus endangering democracy.
Clearly, someone like Myles Allen, worried about the necessity of taking undemocratic measures, is obliged to ignore our calls for debate, in order to protect democracy. One understands his dilemma, and the difficulty of communicating it, since it comes down to: “Don’t make us (the scientific élite) do something we may regret.”

May 27, 2012 at 4:06 PM | Unregistered Commentergeoffchambers

It's worthwhile to visit Steve McIntyre's site for a discussion of the following question:

If the hockey stick was and is "irrelevant" why did it end up as the "icon" of IPCC TAR which we were led to believe was THE most meticulously prepared and authoritative compendium of peer reviewed science supported by 97% of the experts in the field as indisputable and sufficient evidence for action by world governments?

He also points out that the his government's use of the hockey stick to whip up support for environmental policies in a piece mailed to every Canadian household was what first aroused his interest in the data behind the graph. If it weren't for that piece of mail, we would never have heard of Steve and climategate would not have happened. That fact alone shows that the hockey stick is anything but irrelevant!

May 27, 2012 at 4:08 PM | Unregistered CommenterPolitical Junkie

Judith Curry has weighed in with a powerful comment at Climate Audit. It is a succinct statement of why attempts to brush aside discussions of the Hockey Stick and related controversies are uninformed at best (passage is hyperlinked to Climate Audit):

===============================================================


curryja
Posted May 27, 2012 at 10:03 AM

The importance of the hockey stick to the AGW argument is in the context of whether the recent warming is unusual in the context of the Holocene. If the recent warming is not unusual, this leads to two arguments:

i) natural variability may play a larger role in the 20th century warming than is credited by the IPCC
ii) natural variability can potentially swamp greenhouse warming in the future, making CO2 mitigation a relatively ineffective way of controlling climate.

The hockey stick, with its flat handle and the hidden decline clearly gives the impression that the recent warming is dramatic and unusual: caused by humans and can be mitigated by humans.

I regard temperature reconstructions of the past 8,000 years or so to be absolutely critical to our understanding of natural variability in the climate system. And I am worse than unimpressed by the shenanigans surrounding the reconstructions using tree rings.

IPCC participants/proponents don’t seem to think the hockey stick is important because they have already convinced themselves that natural variability between ice age and ENSO timescales is unimportant, and that climate variability on multidecadal to century timescales is radiatively forced (I acknowledge a recent interest by the IPCC in decadal scale natural internal variability). This is a poorly supported assumption, in my opinion

Judith Curry

May 27, 2012 at 4:35 PM | Registered CommenterSkiphil

Let me first thank Professor Allen for engaging us here and encourage him to look past some of the more emotional comments, although they do serve to highlight the 'complexity' of the issue.
Nevertheless, there are several statements in his recent comment (May 27, 2012 at 8:14 AM) that indicate a lack of understanding of skeptics' concerns and so, by pointing them out, may help improve this situation.

To begin with, Professor Allen says "I did not mean to belittle the efforts of Steve McIntyre and other paleoclimate scientists to reconstruct the pre-instrumental period: if they were able to produce reliable reconstructions of global temperatures over the past millennium, and associated forcings, that would indeed be a very valuable resource." Now, my understanding is that McIntyre has never attempted to produce reliable reconstructions of global temperatures, nor does he aim to do in the future. All he's tried to do is check the statistical analyses used by certain paleoclimate scientists in order to assess the veracity of the conclusions that they had draw -- nothing more and nothing less.

The next statement is far more important as it relates to the key concern of most skeptic's. Professor Allen says "The key evidence provided for the headline attribution statement "Most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" was the comparison of model simulations forced with and without anthropogenic drivers with the instrumental temperature record." However, as I pointed our in my original post (May 26, 2012 at 1:49 PM), it seems clear from IPCC AR4 WG1 that "Some processes and feedbacks might be poorly represented or missing" from those models, which means that any attribution to anthropogenic drivers (i.e. CO2) is, at the very least, rather questionable. What compounds this problem is the fact that the uncertainty in attribution, which is assessed by looking at the distribution between a range of models, will suffer from a common bias because any missing factor will be missing from all of them (e.g. the effects of cosmic rays) and will also affect them in the same way, so no amount of additional runs will be able to compensate for this by simply averaging it out.

Finally, I also note that when climate scientists talk about errors or uncertainties, they tend to use statements such as "... "likely" means a 1-in-3 chance that the warming is entirely natural in origin... ", which is a rather loose description that is more akin to the findings of a straw-pole than results from the sort of rigorous error analysis I was taught as a physics undergraduate.

I hope these few observations are taken in a constructive way because, if Professor Allen or any other climate scientist can provide cogent answers, they could help resolve most of the skeptics' dilemma.

May 27, 2012 at 4:48 PM | Unregistered CommenterDave Salt

"The key evidence provided for the headline attribution statement "Most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" was the comparison of model simulations forced with and without anthropogenic drivers with the instrumental temperature record."

The exercise depends on comparing two series, one, model output/s validated by its matching the instrumental series, and second, model output/s with reduced CO2.

The basis for accepting the second as valid is the first matching the instrumental record. How can you use it to raise questions or generate hypothesis about the instrumental observerd temperature?

The argument is circular.

May 27, 2012 at 5:20 PM | Unregistered CommenterShub

Prof Allen writes:

He[William] arrived in a helicopter. Lots of sanctimonious journalists then got upset about his carbon footprint.

The original sanctimonious bunch are the green journalists, activists and scientists who lose no opportunity in calculating the carbon footprint of anything that moves.

It does hit you when others do the same back to you, doesn't it?

May 27, 2012 at 5:24 PM | Unregistered CommenterShub

Hype and exaggeration on climate change are not merely the output of activist journalists. Question for all, which prominent climate scientist said the following on July 7, 2010 (at the start of what did not turn out to be such a horrible 'hyperactive' hurricane season):


"...we're experiencing almost daily reminders of the reality of global warming and climate change."

"We're currently witnessing the warmest temperatures ever globally, and are in the midst of a record-setting heatwave in the US associated with the warmest early summer temperatures ever. Meanwhile, the warmest-ever tropical Atlantic ocean temperatures are likely to lead to a hyperactive Atlantic hurricane season this summer, and Arctic sea ice is on course to plummet to its lowest levels ever this summer/fall."

"Human-caused climate change is a reality, and it's about time we get on to a meaningful discussion about what to do about it."


[find the author of this quotation, which appears to be a submitted comment and not merely some off-the-cuff oral remark, in the article linked..... my point is that there is no distance at all between "hockey stick" reconstructions and alleging unprecedented warming coupled with careless public assertions of doom and disaster... and yes, pace Judith Curry, it is (or may be) highly relevant to know whether recent decades are actually "unprecedented" or not in the Holocene]]

May 27, 2012 at 5:41 PM | Registered CommenterSkiphil

Myles make the rather delusional assertion that regardless of what we public do to mend our ways and which might reward us with a seat at the debater's table, his lot is guaranteed a seat. This despite any reasonable demonstration of accuracy and honesty in what his lot has given the debate so far.

This is a prediction on his part that there is an innate collusion between those who historically pervert climate science (the alarmist team) and those who make the debate table available, albeit on a limited basis (the willing media).

Neither entity is essential to the debate. Neither is helpful to the debate. In fact because of these two entities, debate has actually taken place at multiple elsewheres.

May 27, 2012 at 5:45 PM | Unregistered Commenterdp

Myles sent me the pdf of the paper (which he thought it was open access) which I read. About 50% of the comments here are completely unfair and some just plain stupid to boot. His proposal is intended to minimize the negative economic impact of 'mitigation' (aka reducing CO2 emissions). The idea is to set a maximum total load of CO2 in the atmosphere. We presently have, say, about half this so his SAFE carbon ratio current/maximum = 0.5. Then anyone who wants to sell fossil fuels must sequester half (50%) of the CO2 that buring it releases. As we near the maximum the amount to be sequestered increases up to 100%. In fact you don't need stop at 100% - if we reached 120% then you need to sequester more CO2 than your fuel releases. Grow some trees, burn them, sequester the carbon.

The plan is presently utopian because there is no sequestration technology. I also suspect that immediate economic imperatives will always win over saving the planet! But it's an interesting idea and thanks for making it available here.

May 27, 2012 at 7:22 PM | Unregistered CommenterPeter Mott

Peter Mott, the good professor is lucky to have you explaining his suggestions. Pity he could not do so himself, but he cannot help but confront the fact that here he is asked to first prove the necessity of doing anything. No point in debating what to do until you have decided why you need to do it. But Myles is trying to skip that stage. It really is not sensible to come here and expect to get away with 'the science is settled'.

My plan is still 'see what happens, and adapt'.

May 27, 2012 at 7:39 PM | Unregistered CommenterRhoda

'I do think it is sad for democracy that so much energy in the debate on climate change has been expended on pseudo-debates about the science, leaving no room for public debate about the policy response.'

Ironically, this is poignantly true. As Peter Lilley has pointed out as recently as 7 May in a speech at the Policy Exchange, he was the only MP in the house to seriously analyse the costs/benefits of the Climate Change Act, and one of only three to vote against it. His words-

'However, I voted against the Climate Change Act, not on the basis that the science is still so uncertain, but on the evidence provided to Parliament by the government about the costs and benefits of the Act. The government published an impact assessment of the Climate Change Act - it's always obliged to publish an assessment of the costs and benefits of any piece of legislation - in order that Parliament should know that the benefits substantially exceed the costs and it's worthwhile doing.

I got a copy of the impact assessment. I was the only person to do so - I know that because when I went to the vote office, they said "Oh, we can't find that, no-one's asked for it." But they did eventually find it. And I read it. And this is the government's assessment of the costs and benefits of the Climate Change Act, the most expensive piece of legislation probably introduced in this country since the Welfare State.

'And they said...that the costs of introducing the Act - excluding the transitional costs of the first 20 years, which could be 1% of GDP, excluding the costs of driving business overseas, if other countries didn't do likewise - was, potentially, over £200 billion, equivalent to a down payment of £17,000 for each household in the country - or, sorry, a little lower, about £15,000. The costs were over £200 billion. The maximum benefits, according to the government's assessment - and these are the benefits of reducing climate change worldwide, so most of those benefits accrue to other people - was put at £105 billion....'

http://www.peterlilley.co.uk/article.aspx?id=28&ref=1650

But no matter, that's just wasted money.

The more ominous threat by far to democracy is the threat to independence and freedom itself, and in this case the messenger is the President of the Czech Republic, Vaclav Klaus, that rarest of the rare - a heroically honest and trustworthy politician, and his warnings on both the EU and climate threats to freedom are intertwined.


What we must all reflect upon, is whether, and to what mischievous extent, has the climate issue been promoted, funded, propagandised and dressed up a balloon, a distraction, a feint, a decoy, the chosen vehicle to justify an ever-burgeoning revenue stream in the financial and commodity markets to establish and fund post-democratic global governance.

May 27, 2012 at 8:05 PM | Registered CommenterPharos

@May 26, 2012 at 9:06 AM Myles Allen "It is important to understand that we use physics, and not just correlations of timeseries, in quantifying the greenhouse contribution. The instrumental record does not support a 1K climate sensitivity (the IceMan comment)"

I have sought in vain for the physics behind a 2-3 degree K climate sensitivity. There is a fudge factor called "positive feedback" in the IPCC models, but absolutely no, nil zilch physics to back that up. Basic physics will give me about a 1 deg K sensitivity, but that goes back to Tyndall in the 1880's, some of climatology 101. The instrumental record does better than support a ~1 deg K sensitivity - it gives it as an upper bound.

If you don't believe what your instruments are telling you, then you shouldn't be anywhere near the pilot's seat.

May 27, 2012 at 8:29 PM | Unregistered CommenterThe Iceman Cometh

Yes i will next time Dad

May 27, 2012 at 8:44 PM | Unregistered CommenterJamspid

[Calm down please. Nobody is under any obligation to respond to anyone here]

May 27, 2012 at 9:15 PM | Unregistered CommenterEvil Denier

[Snip]

May 27, 2012 at 9:17 PM | Unregistered CommenterEvil Denier

I talk not about obligation, only courtesy.

I apologise for any intemperance.

May 27, 2012 at 10:02 PM | Unregistered CommenterEvil Denier

Dear Dr Allen,

Thank you for being willing to comment here and even responding to some of the comments we readers have made. However, as several others have said, you've rather missed the points we're trying to make. I asked some questions yesterday morning:

"stabilise global temperatures"

Given that the climate and consequently temperature of the Earth has been in a constant state of change for around 4.6 billion years, and for most of that time has been warmer than today, I have three questions:

1. What makes you think it should be stable?

2. What is the correct temperature at which to stabilise it?

3. Do you think we have sufficient understanding of, and power over, the atmosphere/hydrosphere/biosphere/geosphere/sun to control the temperature in any way?

You may well have missed these, as there are a lot of comments here now, but I really would like answers. You see, as far as I'm concerned, I can't judge the correctness of the science. I'm scientifically trained but in a totally climate-unrelated field - pharmacology - and have no basis for doing that. What I'm after is a justification for the proposed industry and civilisation-destroying actions.

As it happens, my sister works in the renewables industry (specifically offshore wind) and is a full believer in CAGW, and I've asked her and some of her acquaintances these questions too. None of them has ever come up with an answer; all they do is cite the precautionary principle, call me a denier, and say, in effect, that because I'm not a climate scientist I don't know what I'm talking about. I wondered if you had any different answers that might convince me that climate change is a) unequivocally bad, and b) something mankind can do anything about?

May 27, 2012 at 10:22 PM | Unregistered CommenterJanet, Scottish Borders

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