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Scientists' open letter to the Wall Street Journal re: Ridley and Peiser

Posted on 4 December 2015 by Guest Author

The following is an open letter from seven professors contributing to Climate Feedback, in response to an error-riddled Matt Ridley and Benny Peiser op-ed published in the Wall Street Journal.  For a point-by-point analysis of the op-ed, see this Climate Feedback post.

The opinion piece published in The Wall Street Journal by Matt Ridley and Benny Peiser (“Your Complete Guide to the Climate Debate” Nov. 27, 2015) is riddled with false statements, cherry-picked evidence and misleading assertions about climate science, according to an evaluation by a dozen scientists.

The article attempts to throw clouds of uncertainty around the hard facts about climate change that are agreed to by the scientific academies of every major country in the world and the vast majority of the world’s climate scientists. Here are just a few examples:

  •      The statement that the world has warmed at half the rate predicted in 1990 by the Intergovernmental Panel on Climate Change (IPCC) is false. The IPCC predicted that warming between 2015 and 1990 would be between about 0.35 and 0.60 °C. The actual temperature change during that period is 0.5 °C. The statement, besides being false, also ignores that the world has already warmed a total of 1 °C since the start of the industrial revolution, and that as temperatures continue to climb, we are headed into territory not seen in thousands of years. The assertion that the world has been warmer several times in the past 10,000 years is not supported by the most comprehensive temperature reconstructions, and ignores the fact that a continued temperature rise this century will rapidly take the world beyond any climate experienced in that 10,000 year period.
  •      The statement that there has been no increase in the frequency or intensity of storms, floods or droughts also is flat-out wrong. A recently-released UN study found that both the frequency and intensity of storms and floods has increased over the past decade, and that weather-related disasters are occurring at almost twice the rate as they did two decades ago. The authors also ignore the clear increases in the most deadly type of extreme events caused by climate change — heat waves.
  •      The claim that Antarctic ice is increasing is based on an isolated paper that has numerous uncertainties associated with it and is contradicted by many other observations. But more importantly, everywhere on Earth, it is clear we are losing ice and that we have likely already entered a period of major ice shelf retreat, with no mechanisms in sight to stop this retreat over the next hundreds to thousands of years. As University of Bristol Professor Jonathan Bamber has written: “West Antarctica has been losing mass at an increasing rate since the 1990s and that trend looks set to continue. The Greenland ice sheet has also been losing mass at an accelerating rate since around 1995. These trends at both poles are huge signals that are unequivocal and uncontested.”
  •      Finally, the assertion that the cost associated with warming “does not significantly deviate from zero until 3.5°C warming” is one that hardly any scientists or economists agree with, and is contradicted by the overwhelming weight of evidence showing that the adverse impacts from climate change will far outweigh the benefits.

Ridley and Peiser are correct that the challenge of decarbonizing the world is enormous. But obfuscation about strongly supported scientific facts is not the solution.


Prof. Roger Bales, University of California, Merced; Prof. Jonathan Bamber, University of Bristol; Prof. Anthony Barnosky, University of California, Berkeley; Prof. Mark Z. Jacobson, Stanford University;Prof. Steven Sherwood, University of New South Wales; Prof. Veerabhadran Ramanathan,University of California, San Diego; Prof. Eric Wolff, University of Cambridge

For more details about the scientists’ responses to claims made in this op-ed, please read our detailed analysis.

List of scientists who have contributed to this analysis:

Dr William Anderegg, Princeton University
Prof. Jonathan Bamber, University of Bristol
Prof. Anthony Barnosky, University of California, Berkeley
Dr Rasmus Benestad, The Norwegian Meteorological institute
Dr Alexis Berg, Columbia University
Dr Julien Emile-Geay, University of Southern California
Prof. Mark Z. Jacobson, Stanford University
Dr Twila Moon, University of Oregon
Prof. Steven Sherwood, University of New South Wales
Dr Victor Venema, University of Bonn
Dr Emmanuel Vincent, University of California, Merced
Dr Britta Voss, U.S. Geological Survey
Prof. Eric Wolff, University of Cambridge

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Comments 1 to 50 out of 53:

  1. Some Main Stream Media sources provide more helpful infromation for their readers, if readers actually want to better understand what is going on.

    The NYTimes article "Short Answers to Hard Questions About Climate Change" , is just one recent example.

    It is tragic when a media source that really should strive to ensure its readers are well aware of what is going on, rather than being a populist gossip rag, resorts to publishing misleading information because it suits some short-term unsustainable damaging objectives a few wealthy and powerful people.

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  2. Correction in my comment:

    Replace "populist gossip rag" (which I now understand should have been Capitalized) with "popularity pursing gossip rag".

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  3. @1  Your comment "It is tragic when a media source that really should strive to ensure its readers are well aware of what is going on"  is entirely correct but does it encompass contributions such as those by Bjorn Lomborg currently being published in the Australian (see here) to "ensure its readers are well aware of what is going on"?.  Or do such contributions  and indeed the Australian itself, fall into your category "rather than being a populist gossip rag, resorts to publishing misleading information because it suits some short-term unsustainable damaging objectives a few wealthy and powerful people"?

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  4. Apologies I sent this before I saw your correction @ 2

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  5. When I search for this article on the internet I find no reference to the WSJ publishing it.  It is too bad that WSJ refuses to present the mainstream scientific opinion to its customers.

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    For those who can cope, the offending WSJ nonsense-filled garbage is available outside a paywall here. And those who remember that the GWPF (Gentlemen Who Prefer Fantasy) include within their number both Benney and Matt will not be surprised by any misguided nonsense from the pair of them. Dogs bark. Bears misbehave in woods. Benney & Matt have a problem with denial. 

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  7. Coincidentally there is a discussion in WUWT disagrees with several of the points raised here. (See here).  The specific items discussed in WUWT are that:

    1      Global temperatures are lower than models predict

    2      Sea level is rising only 1-3mm per year

    3      The polar bear population is now about 5x that in the 1960s

    4       Extreme weather is historically normal

    The discussions of each appear to be appropriately referenced.

    I am aware that WUWT is anathema to most who comment here but it is one of the most, if not the most, widely read climate blog site. Consequently a lot more readers get their information from WUWT than from other such sites and in this instance will get an entirely different perception on global warming than will readers here.  Although  overall there are, probably, more readers of the WSJ in total than readers of WUWT but the percentage of these WSJ readers interested in climate matters is unknown. 

    Which report is the more credible is, of course debatable, but the WUWT piece is supported by references to published literature and IPCC reports whereas the refutations in the WSJ are not.

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    Moderator Response:

    [Rob P] Sea level is currently rising at 3.32mm per year.

    And the climate models are doing are reasonable job of matching the observations - when adjusted forcings are used (to account for increased volcanic aerosols for instance). As in Schmidt et al (2014).

  8. My final comment is not factually correct.  There are some references given in the WSJ refutation piece.

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  9. The name of this site suggests skeptical minds but instead is simply a play pen for statistical masturbation committed to an ideology.

    I model complex fluid flows and can tell you three things [1] There is absolutely no doubt that the force and temperatures I measure in my lab are agreed upon as valid and real [2] There is no doubt that my ability to model flow is quite limited and these are systems that are orders of magnitude more simple than a planetary climate.  [3] If I was stupid enough to model complex flow around a propeller a thousand times (as many climate models do) and take statistical averages I would actually have the guts to admit I do not know anything worthwhile about the processes involved and leave it at that until I had better analytic techniques.

    In the mantime I read junk science from climate modellers who cannot even agree on a valid, workable data set that has not been adjusted, transformed, filtered to suit their arguments. That is not science. It's a joke.

    Second, any "sciience" that needs this number of runs to determine confidence limits simply means the "science" has no predictive value worth having.  The stability of the models are a joke.

    The fact that many scientists go along with this politicised joke merely reflects the involvement of government and research funding priorities. Contrary to popular opinion, scientists do not die in a ditch, abandon their jobs, mortgages or family financial health to fight against an ideological mob with pitchforks.

    I have several colleagues who find the warmist "data" amusing but we would never speak out against this junk science because of the career repercussions.

    Meanwhile I'm sure you will enjoy looking at statistical tea leaves for a while to come.

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    Moderator Response:


    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

    It particular, you appear to be asserting some very tired denier talking points as if they were true with no supporting evidence at all. This is pure sloganeering and suggests and extremely low level of knowledge of the basic science. Present either data or references to support your arguments in future or your comment will be deleted. Conformance with the comments policy in not optional.

    I would further point out that AGW is not founded on computation models. The models are physical not statistical. I suggest  you actually read the IPCC WG1 so you can make more informed commentary.

  10. @9 Your comment "I have several colleagues who find the warmist "data" amusing but we would never speak out against this junk science because of the career repercussions" is extremely disturbing.  As an ex-scientist. now retired, I am appalled that any scientist or indeed anyone, who questions the perceived wisdom of the modellers is excoriated and may well be dismissed from their position.  Science  conducted by intimidation and haranguing and threats isn't science.  It is more reminiscent of the Spanish Inquisition where heretics were tortured until they recanted.  Here we have eminent professors who attack those that disagree with their views claiming that Ridley and Peiser are obfuscating.  No they're not, they're putting forward a different point of view.  That is not obfuscation but scientific discourse.  The paper by Zwalley et al that states  the Antarctic is gaining ice, is dismissed as an isolated paper that has numerous uncertainties and is contradicted by many other observations.   None of these many observations are specified.  Significantly there is no mention of the comment on Antarctic ice  by Dr Eric Steig, a  Climate Scientist  with many publications on Antarctica.He comments at RealClimate “I think the evidence that the current retreat of Antarctic glaciers is owing to anthropogenic global warming is weak. The literature is mixed on this, about 50% of experts agree with me on this.”  Dr Steig can hardly be described as a denier  so why no mention of his view? 

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    Moderator Response:

    [Rob P] - The Zwally et al (2015) paper does contradict a whole bunch of research on the Antarctic ice sheet. Very difficult to reconcile with Holocene sea level change too. It is only one paper, so care must be taken not to develop single study syndrome. Science will get to the bottom of it.

  11. Genoa @9 : genoa, you seem to have lost touch with reality.

    Worldwide temperatures are rising, sea-levels are rising, and the world's ice is generally [with the possible exception of East Antarctica] melting away. And yet you have a focus on "statistical masturbation" ~ rather than looking at the real world.

    Get real, man. Please exit your mathematical rabbit hole.

    The real world is the actual test for what's going on ~ and since your mathturbation disagrees with the real world, then, quite clearly, you are in the wrong.

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  12. Ryland @7.

    Do get a grip. All you are saying here is that the Wattsupia web site presents the same garbage to the world that the GWPF do. If you do not yet even recognise that there is a profound difference between scientific discussion and the error-filled nonsense presented both by Watts and his chums and by GWPF, then you really should start looking. It might save you making a fool of yourself repeating their error-filled nonsense. Unlike the science, Watts and Co don't don't give a monkeys who they make fools of.

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  13. @12  you clearly missed my closing comment which, to refresh your memory, was "Which report is the more credible is, of course debatable, but the WUWT piece is supported by references to published literature and IPCC reports whereas the refutations in the WSJ are not."  That comment clearly shows I am not "repeating their error filled nonsense" merely putting it forward as a point of view supported by appropriate references to the peer reviewed literature.  Have you yourself checked the references given in WUWT?  Are peer reviewed papers cited by WUWT scientifically inferior to those cited by SkS or RealClimate?  If so why?  And I think some of your remarks are verging on ad homs which I thought were verboten here

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  14. Eclectic

    Like most warmists what you call science is simply choosing the data sets you prefer (I won't even go into the cat fights I've read between alleged warmist analysts over what data sources are credible), transformed and filtered the way you prefer and weighted in the way you prefer to provide a model which, over hundreds of runs, pumps out a performance range you like. Then you pick a date you prefer to identify a trend you prefer and call other date picking "cherry picking".

    Hence a date from 1998 looks like a flat or reduced trend and other dates before that can be chosen to identify a warming trend- if you so wish. I would not call that science or even prediction.

    Worst of all, when long periods such at the period post 1998 don't adhere to the models, real scientists would admit that the models are inadequate and that suggests they don't really understand the underlying processes being modelled. Nope, in climate "science" there is always another "probable" process to bolt onto the models in an ad hoc way. Anything, anything at all to make the data fit. I believe the latest "bolt on" obvious explanation is that the heat is in the deep ocean areas. Perfectly obvious old chap- except it wasn't obvious until the models failed and another excuse had to be invented. Oh and we have no data for that assertion, but it's perfectly obvious that that's the process that's missing. And so it goes, on and on and on and on.

    You do know that the yield equations for the first Bikini nuclear test underestimated by a factor of 3 and led to widespread fallout and evacuation of pacific islands. Even now, yield estimation of nuclear weapons is a very tough problem yet it is several orders of magnitude less complex than a climate projected 100 years ahead.

    Really, what you call a science is just tea leaves, graphs and pick-my-preferred-starting-point-for-the-system-under-observation.

    Then pretend you know more about hugely complex processes working on massive scales than nuclear physicists know about much simpler processes and thereafter leap into nonscientific arguments about "prevention" etc. in order to distract from the "science"

    Basically another 10 years of model massaging and the public and politicians will have had enough. At that point, real scientists will again be able to enter the debate without being stoned to death for being a heretic to the faith and people like Hanson and Mann will be preserved in history as classic examples of what happens- even to science- when it is overpoliticised and turned into a new McArthyism.

    The real damage however will be to science itself. People will and rightly so have much less faith in science and scientists and that is most definitely a bad thing. We already fight crazy anti innoculation loons and this will only add ammunition to the anti-science crowd.

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    Moderator Response:

    [Rob P] - "Hence a date from 1998 looks like a flat or reduced trend"

    The 'eyecrometer' has been found to be a wholly unreliable scientific measuring instrument. This is where statistics comes into play. Only one data set, but Karl et al (2015) found global mean surface temperature warmed at the same rate from 2000-2014 as it did from 1950-1999. Other data sets will come into line in due course as the planet continues to warm.

  15. Moderator

    Thanks for the censorship.

    In reply to your assertion that AGW models are physical and not statistical I would only say that a single die is also physical but only an idiot such as yourself would argue their primary analytic focus is not statistical.

    Thanks for the "privilege" of briefly visiting your joke site and joke discipline.

    See you in 10 years when your religion is dead.

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    Moderator Response:

    [RH] Moderation complaints are off-topic and thus against policy. Please review the commenting policy page.

  16. genoa @9 says:

    "I have several colleagues who find the warmist "data" amusing but we would never speak out against this junk science because of the career repercussions." 

    If we are to take his ravings at face value, and I see no particular reason to do so, this amounts to a confession that he and his colleaques put career advancement above scientific integrity.  Yet on the basis of this we are supposed to take his unsupported word that those scientists he disagrees with are similarly ethically challenged.

    @14 he says:

    "Worst of all, when long periods such at the period post 1998 don't adhere to the models, real scientists would admit that the models are inadequate and that suggests they don't really understand the underlying processes being modelled."

    He thereby commits himself to the view that the trend for any system from localized high points will be the same as the trend from any other point.  Absent this commitment, the expectation is that the trend from such localized peaks will be less than that from other points.  There is a name for this phenomenon.  It is called "regression to the mean".

    Given his clear commitment to the idea that regression to the mean is an invalid concept, we can conclude either that he does not have the scientific expertise he claims (likely), that he is prepared to dishonestly ignore what he knows for his political diatribe, or that his political views so bias his understanding that he cannot find fault with denier cherry picking.

    Finally, it is evident that his contribution is sloganeering of the worst sort.  Perhaps he would like to raise specific detailed criticisms rather than these wild rants that so clearly show his political bias, and render very dubious his claim to scientific expertise.

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  17. ryland @7, the CFACT article posted at WUWT is critiquing the science of the IPCC.  Therefore the correct comparison as to references is between that article (with its one, often misrepresented reference per point) to the IPCC reports with their literally hundreds of references.  Given that, the curious thing is that you are not outraged by CFACT and WUWT for cherry picking outliers from the scientific literature and treating them as overriding the vast majority of the scientific literature, while keeping that contrary literature carefully out of sight and refusing to discuss the relevant issues.

    Your view appears to be that public discourse is intellectually primary to scientific research, no matter how transparently that public discourse misrepresents the actual research.


    As one example of the sort of misrepresentation indulged in in the CFACT article, consider the quotation:

    '“Global sea level is less sensitive to high atmospheric carbon dioxide concentrations than previously thought.”

    – Stanford, Geology, August, 2015'

    Here is the full quote from the Stanford article:

    "To understand the isotopic composition of Pliocene ice, Winnick and Caves began in the present day using well-established relationships between temperature and the geochemical fingerprint. By combining this modern relationship with estimates of ancient Pliocene surface temperatures, they were able to better refine the fingerprint of the Antarctic ice millions of years ago. In re-thinking this critical assumption, and by extending their analysis to incorporate ice sheet models, Winnick and Caves recalculated the global sea level of the Pliocene and found that it was 30 to 44 feet (9 to 13.5 meters) higher, significantly lower than the previous estimate.

    “Our results are tentatively good news,” Winnick said. “They suggest that global sea level is less sensitive to high atmospheric carbon dioxide concentrations than previously thought. In particular, we argue that this is due to the stability of the East Antarctic Ice Sheet, which might be more resilient than previous studies have suggested.” However, a rise in global sea level by up to 44 feet (13.5 meters) is still enough to inundate Miami, New Orleans and New York City, and threaten large portions of San Francisco, Winnick cautioned."

    (My emphasis)

    A long term sea level rise of 9-13.5 meters is not good news.  Nor is it consistent with the message the CFACT article tries to sell with regard to sea level.  Further, as the Stanford article goes on to indicate, the finding has no bearing on sea level rises over the next few centuries, the timescale of interest to the CFACT claims.  There is no question, therefore, that the article is quoted out of context.

    Like the creationists before them, AGW deniers never have a shortage of "references".  They need only take articles out of context, misreport their significance, shepherd a few articles through the peer review process with the aid of unscrupulous friendly editors, and establish "speciality journals" where 'peer' review is entirely restricted to other deniers.  Given this, merely counting the number of references in a popular piece is irrelevant unless are prepared to commit yourself to verifying that the references are from genuine peer reviewed sources (not specialty denier magazines), that they are quote in context and not misrepresented, and that they fairly represent the literature rather than being cherry picked outliers.

    Unless, of course, your only point is that we should stand in awe of the unscrupulous propoganda by CFACT and WUWT.

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  18. I always think of Arhennius when I read a screed like Genoa writes.  In 1896 Arhennius calculated (with  a pencil) the magnitude of the AGW effect.  He was within a factor of two of what has been measured in the 120 years since then.  He predicted that warming would be greater over land than water, greater at high latitude than low latitude, greater at night than during the day, greater in the winter than in the summer and greater in the Northern Hemisphere than in the Suthern.  All these porjections have been shown correct by data in recent decades.

    If it is so hard to project climate decades in advance, how did Arhennius do so well?  I would have thought that scientists today would have more understanding than Arhennius.  Another recent critical poster claimed we needed to wait another 20 yerars to see if scientists are correct.  What is wrong with using the forecasts from 120 years ago to show that the globe is warming as projected?

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  19. @ 15, in ten years you'll be too busy securing the border from those who know you killed the world.

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  20. Tom, reading between the lines of Genoa's @9 comments, does give me the strong impression that he is a technician rather than a scientist in the proper sense of the word.

    Not that there is anything wrong with being a skilled technician in a narrow field : but it is certainly a pity that there seems to be a concomitant lack of that broad outlook on the physical universe, and a lack of that logical and dispassionate appreciation of reality (so requisite in a true scientist).
    Especially in the climate change field, where the physical signs are so obvious!

    The WUWT website is indeed an interesting case in point. Years ago, WUWT was halfway reasonable in its propaganda campaign against the findings of mainstream science. Well, perhaps not quite halfway. And even then, it was the "best" of a bad bunch. However, in recent years it has detereiorated markedly : and nowadays, sadly it rates as moronically desperate. Even more sadly, it still rates as the best of a bad bunch.
    Will WUWT still exist in 10 years? I certaiinly hope so, because its entertainment value (as an example of human folly) will doubtless be accompanied by continuing writhing and twisting as it metamorphoses through the many varying levels of denial of reality. Fascinating in its way : yet not worth a site visit more than every month or two.

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  21. Ryland @13.

    I didn't miss your closing comment @7. You ask of me @13 “Have you yourself checked the references given in WUWT? Are peer reviewed papers cited by WUWT scientifically inferior to those cited by SkS or RealClimate? If so why?” If you can point me at these “peer reviewed papers cited by WUWT”, that would be helpful. I'm not sure I see any. The first bold assertion is certainly not supported by such references.

    I particularly like the third reference, quoting NASA. This is of course a link to a cutting from that well-known scientific journal The Canberra Times from the April Fools Day 1990 edition. Anyone with half a wit would find that there is a better reference to the quote which turns out to be our old friends Spencer and Christy, dear old Woy having been a NASA man until he left to go to join his chum Christy in 2001. I don't think the passage of time has been very kind to their findings presented in that paper.

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  22. Eclectic @20.

    I have a climate denier friend who references Judith Curry's web site far more often than WUWT. Based on my limited reading at both sites, I think that Curry's site may outrank WUWT as "the best of a bad bunch."

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  23. The popularity of claims made by the producers of unsubstantiated nonsense and gossip is indeed part of the challenge of getting leaders who can tend to allow their decisions to be swayed by popular opinion to act contrary to the rank ranks of the supporters of undeservingly popular and wealthy people.

    Science will always stuggle to be as popular as appealing gossip and nonsense claims that many people are inclined to like to hear because they suit their self-interest.

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  24. MA Rodger @21, what is missing from your comment is the record of adjustments made to the UAH dataset since that 1990 press release:

    Of course, we are not onto version 6.  Aparently ryland is of the opinion that a reference that is 22 years out of date (dating from that first adjustment) is suitable.  Of course that it is so dated must be carefully kept from the intended audience of the CFACT/WUWT article.

    I submit, by the way, that ryland's challenge to you implicitly requires the same standard of himself.  That is, if he questions your right to rebut the article without "... you yourself [having] checked the references given in WUWT" and established that the"... peer reviewed papers cited by WUWT scientifically inferior to those cited by SkS or RealClimate", then he is not entitled to link to the article as worthy of discussion without having himself checked all the references and endorsed them as being up to scratch.  Sauce for the goose, as they say.

    And on that standard, he has clearly attempted to mislead the reades at SkS as to the quality of the articles to be found on WUWT - endorsing them as being worthy of consideration and well referenced when they are based on references that are out of date, non-peer reviewed, out of context and (at the very best) outlier positions.

    If we apply the expectation that he checks the articles he puts up, and stands by the quality of their argument and/or references we can perhaps get rid of his endless, mendacious repetitions that he is "merely putting it forward as a point of view supported by appropriate references to the peer reviewed literature", when we all know he is using them as stalking horses for opinions he agrees with but is not prepared to defend with any integrity.

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    Moderator Response:

    [RH] Tweaked image size.

  25. Regarding frequent reference above to claims from WUWT that global warming "stopped" or "paused" or "slowed" or whaever beginning 1998 or so...

    Most of the articles at WUWT regarding this were written by Chris Monckton, who proclaims whenever RSS releases its monthly data, "No global warming for xxx months!" and provides a graph to prove it. Put aside 1) the reality of regression to the mean, as has already been mentioned above, and 2) Mockton's flatline of "no temperature increase" is at a point significantly higher than the current temperature trendline over the last century (which means some natural phenomenon, unexamined by Monckton, created a sudden climate discontinuity that raised global temperatures far above the current ~1 C warming that most climate scientists accept).

    This means, if one were to accept the Monckton/WUWT thesis that there has been no warming since c. 1998, then one would also have to accept not only that regression to the men doesn't happen, but also that the world is significantly warmer than any dataset currently shows, and that this sudden discontinuous leap was caused by a phenomenon no one has even hinted at, no one understands, and even Monckton hasn't acknowledged.

    But as I said, put that aside. The biggest problem I see with the Monckton/WUWT thesis is that the date of when the "pause" started keeps changing. If you examine Monckon's graphs over the last couple of years, you'll see his start date keeps creeping forward in time. (I have documented this elsewhere, in an article where I also steal a graph or two from SkS.) Whatever physical process started the "pause" keeps altering its starting point somewhere in the past. Mockton doesn't adequately explain how this happens.

    The alteration of "pause" start date indicates the "pause" itself is nor more than a statistical oddity, not a reflection of any physical reality or actual physical process. It also indicates the denier meme about a "pause" is based on an intentional and clumsy bit of fraud.

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  26. @Ryland 10.

    You write: "I am appalled that any scientist or indeed anyone, who questions the perceived wisdom of the modellers is excoriated and may well be dismissed from their position."

    I'm sorry but your indignation is as unconvincing as it is unmerited. If this was really happening we would have actually heard about it by now. But in 15 years of following this subject quite closely I can't remember a single instance of someone losing their job in a significant scientific institution or failing to secure one becauser of their views about climate change or any aspect of it. If they had, they would have nothing to lose by coming forward and citing chapter and verse.  So where are they? And yet we hear this feeble mantra wheeled out regularly without any supporting examples. The simple fact is: the claim of academic suppresion is a fallacious and fictitious notion used to explain the almost complete absence of peer-reviewed science supporting the various (and mutually contradictory) contrarian positions - such as the ones set out by Genoa.

    Real scientists, retired or otherwise, know that general views on broad subjects are irrelevent to careers in science. What matters is research and publication, usually in a very narrow field (unless you happen to be Albert Einstein or someone of that stature). Generally speaking, the more surprising the conclusions, the better.

    In short, I don't believe Genoa's claims. They're as incredible as his fulminations about cherry picked data points, and just as divorced from reality. 

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  27. Looking at the article referenced by ryland @7, I found this statement

    Arctic sea ice is up by at least a third after a cool summer in 2013. “It would suggest that sea ice is more resilient perhaps,” says Rachel Tilling, University College London.” – The Guardian, July 2015

    If you follow the link provided by WUWT to The Guardian here you will see that the quote WUWT provide is not from Tilling at all, but is in fact from the main body of the article. Tilling goes on to place this "resilience" in context:

    Tilling said: “You see Arctic sea ice as dwindling and in decline, but then there is a cold year and you get some of the ice back. It shows there is hope for Arctic sea ice,if you can turn the clock back to colder temperatures, which would need huge reductions in carbon emissions.

    (my emphasis)

    But this slopiness appears to be a prevalent feature of WUWT.

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  28. Philip64, Genoa's rant is nothing more than argument from incredulity and alleged anecdote, both logical fallicies, and offers nothing what so ever in the way of verifiable evidence. Frankly, there is nothing there to believe or disbelieve.

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  29. Philip64@26

    You comment "But in 15 years of following this subject quite closely I can't remember a single instance of someone losing their job in a significant scientific institution or failing to secure one becauser of their views about climate change or any aspect of it."

    Perhaps you need to follow it a bit more closely.  Bjorn Lomborg was denied a university position here in Australia because of his views of climate change.  He is not a "denier" but believes the dangers of climate change are overstated and there are more pressing problems. (see here)

    You will note no doubt that the vice president of the Academic Staff Association states

    "This isn't about censorship at all ... Lomborg is not a climate [change] denier; he believes the scientific evidence which overwhelmingly shows that climate change is happening, he just debates the economics of how we should deal with it," Mr Bunt said.  But he would say that wouldn't he?

    A more telling quote is from Greens Senator Rachel Sieweret who is reported as saying:

    "It was very clearly the Government's design to get someone in place that was running a different argument on climate change, to try and suggest that climate change isn't as significant an issue as it is," Senator Siewert said.

    "It was bad science, and I'm pleased that UWA has realised that.

    "[The Federal Government] clearly had a political agenda, and it was a mistake for the University of Western Australia to go along with it."

    As you can see Bjorn Lomborg's views cost him a position at UWA, which is where I got my PhD from.  I do not support the actions of UWA in this instance.

    You also may not of heard of Murry Salby and Bob Carter both climate change sceptics. Salby was dismissed from his position and Carter was not re-employed. You can read about it here and here.  The two references, the second of which is by Dana Nuccitelli give quite different views

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    Moderator Response:

    [Rob P] This whole persecution discussion has run its course. Any more comments in this vein will be considered off-topic and result in deletion. Stick to the science.

  30. With the hopeful permission of the moderator, and in respect to ryland @29:

    1)  Bjorn Lomborg was not denied a position at the UWA.  Rather, the AGW denied and then PM of Australia offered the UWA a special monetary grant on condition that they set up a "consensus center" administered by Lomborg.  The center was not to employ Lomborg, but other researchers by his invitation working on his flaws "Copenhagen concensus" model.  This was money entirely outside the normal academic grants process, and was not based on any academic assessment of the merits of Lomborg's work.  It was quite rightly rejected as a blatant attempt to provide Lomborg an additional platform for his pontifications which were considered desirable by the government not because of academic merit but because of political convenience.

    No attempt by Lomborg to be employed in Australia via normal academic processes has been rejected, and nor should it be.

    2)  Salby was sacked for: a)  Not undertaking his prescribed teaching load; b) failing to teach a course he was directly instructed to teach; and c) using university funding without permission to undertake a trip to Europe he was expressly denied permission to make as it conflicted with his teaching duties.  

    3)  Bob Carter was not sacked from James Cook University, and nor could he be as he had already retired.  He was not offered a renewal of his annual, unpaid position of adjunct professor because he was not undertaking the duties thereof.  That the failure to renew the offer was not due to his opinions on global warming is evident from the fact that the position has been renewed annually from 2002-2012, ten years over which he has been as vocal on climate change as he is now.  From JCU:

    "Dr Carter’s very prominent public contributions to the climate change debate is not something new. He has been promulgating his views, which of course he was entitled to do, for many years while holding an adjunct appointment. But what has changed over the years is the level of his contribution to the School of Earth and Environmental Sciences where he held his adjunct appointment.

    Academics holding adjunct appointments are expected to contribute on a regular and ongoing basis to one or more of the following University activities:
    • Teaching;
    • Collaborative research;
    • Postgraduate supervision; and
    • Staff and student consultations.

    The key question for an adjunct appointment is: “Proposed activities and Perceived Benefits to the School”. While Dr Carter has continued his own research and gives “public talks and advice about climate change and climate change policy” – again as he is perfectly entitled to do – such outreach activities are not related to the work of the School, and do not meet the need to contribute to the School as outlined above.

    The simple fact was that in the School’s view Dr Carter was no longer undertaking any of the activities within the School of Earth and Environmental Sciences that is required of an adjunct."

     In short, the adjunct professorship was not renewed because he was no longer teaching, undertaking collaborative research, supervising any post graduates or consulting with staff or students.  Rather, he was merely using his office for non-academic purposes.

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    Moderator Response:

    [Rob P] I'll let this one slide in the interests of having 'both sides of the story', but no more thanks. 

  31. Phil @27, the Tilling quote does not, as you indicate, come from the Guardian article.  It does, however, come from a BBC article.  So the quote is misreferenced rather than nonexistent.  That said, the full quote reads:

    ""It would suggest that sea ice is more resilient perhaps - if you get one year of cooler temperatures, we've almost wound the clock back a few years on this gradual decline that's been happening over decades," said Rachel Tilling.

    "The long-term trend of the ice volume is downwards and the long-term trend of the temperatures in the Arctic is upwards and this finding doesn't give us any reason to disbelieve that - as far as we can tell it's just one anomalous year.""

    It is evident from the following sentence which I have highlighted that the quote is taken out of context rather.  Being fair to the authors of the CFACT piece, the quote was repeated by a number of other news sources, some of which may have taken it out of context (I am certain the one at the Telegraph did).  They may merely have been guilty of inadequate research in this context.  The mis reference, however, is highly suggestive that they were trying to launder a report from an obvious denier source by referencing an article from a more credible source.

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  32. ryland @40, of course the funding of the Climate Commission was done for a political purpose, although given that - at least the Gillard government had the good sense to appoint people with relevant competencies including several climate scientists, a leading public servant with domain knowledge, two business men including the president of the australasian branch of a major fossil fuel company (BP), and whose reports have been highly praised by leading climate scientists.  In contrast the "concensus center" could only drum up as its lead head a man found not guilty of scientific fraud only on the basis that he was no scientist; and whose "consensus" methodology is to cherry pick experts based on known position in various issues to ensure the proper balance in the final outcome.

    And of course GetUp's campaign was political.  That does not change the political nature of the funding in the first place.  It does not change the fact that the Liberal party tried to white wash the center with academic respectability by bypassing normal funding and hiring proceedures that are based on academic merit.  It does not change the fact that given the clearly political nature of the funding, no university should have had a bar of it as a matter of academic integrity, just as they should not have a bar of dismissing academics because their opinions are politically unpopular.

    Your problem is that you want it both ways.  You want to criticize UWA and Flinders because rejection of the funding was based on his views (which is not actually true); but think it would be OK for them to accept funding to set up his center when that funding was only made available because of his views on climate change.  If the former is unacceptable (it is), then the latter is also unacceptable.  And what you are ignoring was that it was not just GetUp that protested the funding, but a large number of academics on the principled grounds I have defended here.

    Similarly, you want to pick out three cases as people dismissed, rejected, or not renewed in positions because of their views but ignore the very many more scientists who lost their position due to the Abbot government cut backs on research funding (again politically motivated).

    Finally, I have reread the moderators direction @29 and it was specifically directed at you.  I assume it was directed at you because of the way you went of into left field rather than defending the obvious flaws in the "references" or the CFACT/WUWT article.  Having failed in your argument there, you redirected.  And now, having failed again you have begun a campaign of moderation complaints to get the very clear evidence (quoted and linked) that your charges are without basis deleted. 

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  33. Tom Curtis  Read Philip@24 to see why I went into the details in 29.  I was responding to not initiating what you state is "left field"

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  34. This article says "The statement that the world has warmed at half the rate predicted in 1990 by the Intergovernmental Panel on Climate Change (IPCC) is false. The IPCC predicted that warming between 2015 and 1990 would be between about 0.35 and 0.60 °C."

    What is your reference for that 0.35 to 0.60 °C range?

    Looking at the Policymakers Summary of the IPCC first assessment report (SPM link) I find on page 5 the following text: "Based on current model results, we predict:
    • under the IPCC Business-as-Usual (Scenario A)
    emissions of greenhouse gases, a rate of increase of
    global mean temperature during the next century of
    about 0 3°C per decade (with an uncertainty range of
    0 2°C to 0 5°C per decade),"

    I note that the prediction of the trend is over the next century, and assume that the predicted trend rises with the passing of time, so the expected numbers over the first 2.5 decades should be lower. 

    Assuming a lower, constant, trend, I read the central IPCC prediction for 1990 to 2015 as 0.75°C, with an expected range of 0.5 to 1.5°C.

    Please explain how you read the FAR to get a 1990-2014 range of 0.3 to 0.6 °C.

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  35. The next bullet point in the article says " A recently-released UN study found that both the frequency and intensity of storms and floods has increased over the past decade, and that weather-related disasters are occurring at almost twice the rate as they did two decades ago."

    In the link to the EM-DAT (not IPCC) Report there is a section on page six that appears to be the source, but the very next sentence starts off as "While scientists cannot calculate what percentage
    of this rise is due to climate change, .......  "


    Yes, the previous sentence says "In total, EM-DAT recorded an average of 335 weather-related disasters per year between 2005 and 2014, an increase of 14% from 1995-2004 and almost twice the level recorded during 1985-1994."  But then the next sentence channels Bjørn Lomborg  and Pielke Jr by saying "While scientists cannot calculate what percentage
    of this rise is due to climate change, predictions of more
    extreme weather in future almost certainly mean that we will
    witness a continued upward trend in weather-related disasters
    in the decades ahead"


    Is this the section of the report you relied upon, or is there some point in the report by Centre for Research on the Epidemiology of Disasters that discusses climate change and observed increases in disasters?   I have noted several places where the report ties observed increases with better reporting, but none that link observed increases to climate change.

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  36. Tom Curtis @31.

    You suggest we could be fair to the authors of CFACT in that they are but "guilty of of inadequate research in this context." You then continue suggesting that this is also indicative, but only indicative of, greater crimes.

    There is actual evidence of such greater crimes.

    The second bit of quotation supporting the CFACT assertion that "Sea level is only rising 1mm to 3mm and has been for generations" fundamentally mis-represents their reference Dangendorf et al. (2015) 'Detecting anthropogenic footprints in sea level rise.' The paper makes very plain that it discusses local and global Mean Sea Level and that these must be addressed seperately. The quote from CFACT entirely ignores the distinction and so makes fools of those who read it unquestioningly. As there is no sign that I can find of this being the work of others, so with no signs of plagiarism CFACT cannot claim the defense that they were made fools of themselves.

    The first reference supporting the SLR claim is also worth a few words. The link no longer works. Indeed, this was predicted by a denialist website that also uses the link. This denialist website page is suggesting that nod-nod-wink-wink such censorship is/will-be used to stop embarrasing AGW facts being spread around. Such a view is a little strange given the same embarrasing AGW fact is provided by the NOAA site's FAQ page and there it is attributed to IPCC AR4. Indeed AR5 gives a figure  for GSLR in the SPM that is marginally lower. But quoting from that NOAA FAQ page or the IPCC SPM is less satisfying for denialists as the rate of GSLR provided there obviously applies to the last century not to the present.

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  37. Charlie A,

    You ask for explainations of the letter.  It was written by a group of experts who do not post on this board.  If you want an answer from the authors you need to post where they read and post.  I would try RealClimate.

    I do not understand your calculations at 34. You say the maximum increase in temperature was projected at about 0.3C per decade.  You say you discount the rate and over 2.5 decades you expect 0.75C warming.  Since 2.5 times 0.3 is 0.75, there is no discount in your calculations.  Your error bars are also incorrect. If you discounted the rate (as you claim is necessary) you would get what the letter says.  

      This post analizes the FAR. the key point is:

    "The collapse of the former Soviet Union led to a decimation of Soviet Block industry which nearly halved Eastern European emissions. In addition, the Montreal Protocol put an end to manufacturing of some of the most potent chlorofluorocarbons (CFCs, which are greenhouse gases), and its effect has been swift. Also, growing global recognition of the threat of climate change has rapidly increased the adoption of renewable energy, both in the US and especially in Europe; government subsidies such as feed-in tarrifs have encouraged this trend. Meanwhile, the rising price of fossil fuels has led to slower economic growth than most would have predicted in 1990.

    "If we look again at the temperature predictions for Scenario D, the FAR predictions were increases of 0.25, 0.17, and 0.11°C per decade, based on sensitivities of 4.5, 2.5, and 1.5°C for CO2 doubling, respectively. The central figure of 0.17°C, based on the best sensitivity estimate, is virtually identical to the actual observed temperature increase over the past 30 years (Figure 4). Foster & Ramstorf (2011) puts the increase at 0.16 +/- .02°C per decade."

    You cannot take the worst case projected in 1990 and say it is incorrect when the forcings were for a different case.  You have to take the increase projected for the forcings that actualized.  Your estimates of projected increases are double what was actually projected.

    You can answer your questions in your other post by using the search button at the top of the page.

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  38. Charlie A @33.

    If you scale Figure 9 from the FAR SPM, the Scenario A central projection 1990-2015 comes out at +0.67ºC  which is not greatly less than the +0.75ºC from the average over the 21st century. But if you examine the rest of the SPM it is evident that Scenario A poorly represents the outcome 1990-2015. GHGs in 2015 - CO2 lies between the Scenario A & Scenario B values, CH4 lies below Scenario B & CFC-11 well below all scenarios. So, as michael sweet argues @37, Scenario A is inappropriate to use. There are however the other scenarios. Scaling Figure 9 for the other scenarios instead of Scenario A (they are still pretty closely grouped in 2015) and the rise is +0.44ºC which fits with the +0.35ºC to +0.6ºC you were enquiring about as well as being close to the rise of a linear trend through the 1990-2015 global temperature record +0.42ºC±0.1ºC(2sd).

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  39. Charlie A @38, the BAU (scenario A) projections from the IPCC FAR are shown on this graph:

    By pixel count, I have determined the increase from 1990-2015 to be 0.64 C [0.48-0.91], leading to a mean decadal trend of 0.26 C per decade [0.19-0.36].  Your estimate of the BAU prediction is, therefore, [0% and 65%] to high.  Given the 0.163 C/decade trend over that period (GISTEMP), that means the BAU estimate from IPCC FAR is 60% to high compared to the observed rate.  Already we detect significant exageration by Ridley and Peiser.  (That is probably based on based on treating the trend to 2015 as equally the trend to 2100, which as you note is an error.)

    Further, the Scenario A projection is not the IPCC FAR prediction.  The reason for the various scenarios, and for calling them projections is that the IPCC does not attempt to predict the future growth of forcing agents.  Rather it considers various plausible scenarios and makes predictions for those so that the uncertainty in the projections is not further exagerated by uncertainty regarding political and economic decisions into the future.

    In this case, and in particular the Business As Usual in 1990 assumes:

    1)  No massive reduction of British coal production under Margaret Thatcher;

    2)  No breakup of the Soviet Union and consequent massive reduction in very polluting Soviet block factories;

    3)  No Kyoto protocol with the consequent massive reduction in CFC emissions; 

    4) No plateauing of CH4 concentrations through the 1990s; and

    5) No major uptake of renewable energy and reduction in energy intensity  due to the e-revolution.

    I presume the difference in forcing between the BAU scenario and the very much not BAU reality accounts for the additional difference between "predicted" temperatures as noted in the scientists letter.  Certainly that difference means the 60% overestimate is the upper bound of the overestimate by the IPCC FAR.

    MA Rodger and Michael Sweet have already raised these points - but it is useful, I think, to remind people how very much not BAU the 1990s was.  The lazy assumption that what happened was automatically BAU repeatedly made by deniers is as intellectually impoverished as the assumption that the first few decades of trend will be the same as the centenial trend.

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  40. #39 Tom says BAU scenario assumes "3) No Kyoto protocol with the consequent massive reduction in CFC emissions; :"

    That is incorrect.  FAR explicitly says that they assume Kyoto Protocol will be implemented in most countries as part of the business-as-usual scenario.

    Later on I will extract the FAR BAU scenario assumptions on carbon/CO2 emission and compare them to actual.   IIRC, the CO2 emission have actually been higher than those assumed in FAR's Business as usual scenario, in spite of things like reduction in British coal mine production.  

    The main problem with the prediction made by the IPCC in 1990 is that they ignored aerosols.  

    Yes, if you go back and correct the predicted forcings to something closer to what they actually have been, then the _revised_ predictions are more in line with what happened, but the headline/main/executive summary prediction was for BAU.  Not for scenario B.  Not for the more aggressive emissions reduction scenario C.  And definitely not the most aggressive possible emissions scenario simulated, Scenario D.

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  41. Charlie A @40,


    I find it very difficult to believe that the 1990 IPCC First Assessment Report explicitly adopted as BAU the 1997 Kyoto Protocol.  Indeed, based strictly on temporal logic, it cannot even have allowed for the 1992 UNFCCC which preceded Kyoto.

    Your confusion appears to relate to mine, in that I incorrectly referred to the Kyoto Protocol (which was also implimented, and is another difference between BAU and what actually happened) and the Montreal Protocol, which is indeed referred to in the IPCC FAR, which states with regard to the BAU scenario:

    "For CFCs the Montreal Protocol is implimented albeit with only partial participation." (My emphasis).  How partial can be seen by comparing the BAU projections for CFC 11:

     with what actually happened (fourth panel):

    You will notice that in reality CFC 11 concentrations peaked at just above 250 ppt prior to 1995, and then when into decling.  The projection, in contrast has BAU concentrations at 400 ppt by 2010, ie, 60% higher, and still rising rapidly.  Every IPCC FAR scenario significantly overstates CFC 11 concentrations relative to what happened.  So, even correcting for the appropriate protocol, my statement was substantively correct, and far less misleading than stating that "FAR explicitly says that they assume [Montreal] Protocol will be implemented in most countries as part of the business-as-usual scenario" without massive further qualification.


    Here are the IPCC FAR CO2 concentration projections:

    It shows CO2 concentration in 2015 of 415 ppmv for BAU, 15 ppmv greater than has actually happened.  That difference is made up of a much slower than projected rise in the 1990s partly compensated by a faster than projected rise in the 2000s due to China's rapid economic growth.  While the overestimate relative to what actually happened is smaller for CO2 than for CFCs and CH4, it is still an overestimate.

    Overall, adding all forcing together the CO2eq concentration has increased in line with scenario B rather than BAU:


    The 'headline' prediction of the IPCC FAR was, and I quote:

    "Based on current model results, we predict:

    • under the IPCC Business-as-Usual (Scenario A) emissions of greenhouse gases, a rate of increase of global mean temperature during the next century of about 0 3°C per decade (with an uncertainty range of 0 2°C to 0 5°C per decade), this is greater than that seen over the past 10,000 years This will result in a likely increase in global mean temperature of about 1°C above the present value by 2025 and VC before the end of the next century The rise will not be steady because of the influence of other factors
    • under the other IPCC emission scenarios which assume progressively increasing levels of controls rates of increase in global mean temperature of about 0 2°C per decade (Scenario B), just above 0 1°C per decade (Scenario C) and about 0 1 °C per decade (Scenario D)"

    That is, the 'prediction' was tied to a particular scenario, with the effect that no explicit prediction is made if the scenario did not occur.  There is no further prediction that BAU will occur.  Saying that "the headline/main/executive summary prediction was for BAU"  is a straightforward misrepresentation. 

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  42. You omitted the most basic graph -— the one showing the IPCC FAR projected emissions for the various scenarios.

    FAR Carbon and Methane Emissions Projections

    When I get time I'll add the actual emission lines to the graphs, but as I noted above, I'm pretty sure that the actual emissions exceeded the BAU scenario.   They _definitely_ exceeded the Scenario D that is being used as the scenario with the forcings that most closely matched observed.

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    Moderator Response:

    [AS] Fixed picture width. Please keep all figures no more than 550 pixels wide. Thanks!

  43. Joel_Huberman @22 : thanks Joel, for your link to Professor Curry's website ~ though I am not sure I would describe it as "better" than WattsUp site. Certainly, Curry's site is more upmarket than WUWT ~ the comments posters seem to be twice as educated and half as rabid as those of WUWT. Not that that's saying much!

    It is more than a year since I previously looked at the Curry site. Not much has changed there. She continues with a multi-pronged attack on the mainstream climate science: At times she takes a Lomborgian It-won't-be-bad-ist position / other times she does a lot of fence-sitting by using the "Uncertainty" gambit / other times she follows the usual denier meme by cherry-picking and elephant-ignoring.

    Just in case anyone should think Professor Curry is not a gold-medal climate science denier :- please consider a few of her (recent) quotes:

    " . . . we need to open up the debate on the causes of the warming." [my emphasis]

    "I think that by 2030, temperatures will not have increased all that much."

    "The differences between the U.S. Democrats and Republicans on this issue [AGW] is rooted in their preferred policies, not so much the mainstream science." [my emphasis]

    Yes, the Curry website is much, much lower-key than the typical mouth-frothing denier website. But as you read into it, you find that her website simply uses a different approach in obfuscating of science and of clear thinking about the issues. It is an approach which uses obfuscation through a chaotic welter of words.

    Yes, it is "different" ~ where the average [American] denier complains that Science Is Being Politicised . . . we find that Curry complains politics is being "scientized". [Marvellously droll, eh? How dare any politics be influenced by scientific facts!]

    Alas, if you want practical, useful information, then you will find that neither Curry or WUWT is worth going to.

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  44. Charlie A @42, first, and most fundamentally, the most basic graph for this issue is the projected change in radiative forcing due the the change in all GHG concentrations (third graph in my post above).  Given that the observed change in radiative forcing is significantly smaller than that projected for scenario A, it is a distortion of the IPCC FAR projections to use scenario A as their equivalent to what realy happened.  

    Sticking just to CO2, the most basic graph is CO2 concentrations.  That is because change in forcing, and hence change in temperature, is a function of change in CO2 concentration - not in CO2 emissions.  

    Change in concentration is in turn, to a close approximation equal to change in cumulative emissions multiplied by the airbourne fraction.  Therefore, if the IPCC FAR did indeed underestimate CO2 emissions, that in turn means they are using too small an airborne fraction with the two errors approximately cancelling out.  And because they approximately cancel out, they have negligible impact on the model/observation comparison.

    In fact sometimes this self cancelling pair of errors is used to deliberately simplify projections.  That is, rather than estimating total anthropogenic emissions (ie, LUC emissions plus industrial emissions), an estimate of industrial emissions alone is used, with a larger airborne fraction used.  The difference in the net increase in CO2 concentration between the two techniques turns out to be negligible.

    What is more, that appears to be what has been done in the IPCC FAR scenarios.  In particular, Fig 1.5 (page 13) shows the estimated annual average industrial and LUC emissions for the decade, 1980-1989 as 5.4 and 1.6 GtC per annum respectively.  The combined total, 7 GtC per annum is 0.4 GtC larger than the 1990 emissions estimate for Scenario A (BAU).  Had the scenarios estimated both emissions, the starting estimate should have been 7 GtC plus 0.5 the decadal trend in emissions, or approximately 7.7 GtC.  Instead it is 6.6 GtC, approximatley the 1987 estimate plus trend for the intervening years.

    If that is what has been done, the apples to apples comparison is observed industrial emissions to projected industrial emissions.  In that case, observed industrial emission begin lower than projected (6.1 vs 6.6 GtC) and rise more slowly.  The gap therefore increases, with projected emissions exceeding observed by 1.3 GtC in 2000.  Thereafter the more rapid observed increase in the 2000s closes the gap until they crossover in 2010 (the last year of observed data I have).  Projecting the oberved trend, by 2015 the gap widens so that by 2015 observed emissions exceed projected emissions by 0.7 GtC.  Although projected emissions are less than observed emissions in the final year, however, projected cumulative emissions always exceed observed cumulative emissions.  And it is cumulative emissions which is the critical value for determining CO2 concentrations, and hence radiative forcing.

    If we include LUC and industrial emissions, as can be expected by the initial projected values falling short of the mean for the previous decade, observed emissions and cumulative emissions always exceed projected emissions.  But in this case, there must have been an error in the airborne fraction that more than cancels this error as noted above.

    So, in the one (more likely case) projected cumulative emissions exceeds obeserved cumulative emissions throughout; while in the other case twin errors more than cancel out so that explecit emissions estimates are irrelevant. 

    What it looks to me that you are doing at the moment is, faced with a mass of evidence showing what actually occured was not the 1990 BAU projection, you are desperately seeking to cherry pick the one graph that might allow you hold to that belief, no matter how much contrary evidence you need to ignore.  If that is indeed what you are doing, say so.  "A man convinced against his will is of the same opinion still", and if you are resorting to grasping straws to retain your beliefs, clearly you are at best being "convinced against your will" and I have no wish to waste further time on you.  But if that is not what you are doing, it is about time you acknowledged the mass of contrary evidence to your opinion already shown above.

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  45. Charlie A @42.
    You will be pushing your luck trying to make a comparison between the different Scenarios and the measured outcome using the FAR emissions graphs. Those graphs aren't that accurately drawn. The atmospheric consentrations graphs provide a more robust comparison and in particular the CO2 graph (as shown @41). Scaling that shows 400ppm CO2 hits 400ppm in 2007 for Scenario A & 2019 for Scenarios B, C & D. Precisely when we did arrive at 400ppm CO2 depends on where you are measuring. The NOAA global measure latest NOAA global measure (September) is still a month or so short of the 400ppm. But taking MLO as the likely candidate measure for somebody in 1990, we reached 400ppm this March. This, with the comparisons for other GHGs, is the basis my comment @38.

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  46. It really is pointless arguing with contrarians (to use an uncontroversial description) because they are quite happy lying about the facts and, of course, cherry picking. They also have no single coherent theory to explain the warming since pre-industrial times, but that doesn't stop them.

    However, the publishing of a Matt Ridley article on the new Scientific American site (which doesn't appear to allow comments) is sad, indeed. Sci Am generally publishes sound articles on the subject, so I was a bit taken aback that they would include an article by a prominent contrarian that is riddled with errors. It is any wonder that it's so hard to get significant action on this issue?

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  47. #46"quite happy lying about the fact and, of course, cherry picking"

    Interesting response in that my "lie" is a post of the IPCC graph of projected emissions, and my cherry picking is to show the driving force of humans — emissions — rather than the incorrectly calculated forcing.

    the dramatic reductions in CO2 emissions of scenario D did not happen, but that is the scenario which several people have said should be treated as the IPCC 1990 prediction.   Why?  Because the erroneous conversion from emissions to forcing caused a best match between forcing projections and observations if we use scenario D. 

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  48. Charlie A, @47, continues to insist that it is emissions rather than forcing which is the direct driver of temperature change.  He also continues to insist that in determining the relevant scenario for comparison, only CO2 emissions should be considered, thereby excluding the very large reductions in CFC and CH4 emissions in the observed data relative to those projected in the FAR BAU scenario.  Further, he insists the forcing comparison from Table 2 here is invalid because "the erroneous conversion from emissions to forcing caused a best match between forcing projections and observations if we use scenario D".  (Note again, forcing is a function of GHG concentrations, not emissions so that this objection is entirely wrongheaded.) 

    As it happens, the table (reproduced below) does contain one inaccuracy, and is out of date to boot - covering the period to 2010 only.

    Table 2: FAR Figure A.6 radiative forcing projections from 1990 to 2010

    ScenarioChange in forcing, 1990-2010
    BaU+1.23 W/m²
    B+0.78 W/m²
    C+0.70 W/m²
    D+0.63 W/m²
    Actual+0.63 W/m²

    Adressing the second issue, by pixel count on Fig 1.6 of the IPCC FAR, the approximate forcing changes from 1990-2015 are:

    BAU: 1.5 W/m^2

    B: 0.9 W/m^2

    D: 0.8 W/m^2

    'Actual': 0.77 W/m^2

    The plot for C is indistinguishable from those of B and D at that time, so I have not data for C.

    The article says, "The actual forcing increase of +0.63 W/m² is from NOAA's Annual Greenhouse Gas Index."  Of course, that excludes changes in forcing from changes in albedo and/or insolation.  They are likely to be negative over that period, however.  Further, they are not included in the FAR model projections, so using the GHG only forcing gives the best apples to apples comparison.

    So far we continue to track at about the level of scenario D.  That is unsurprising given that CO2 industrial emissions have tracked the BAU scenario projections from 2010 to present, while CFC concentrations continue to track well below even scenario D levels.

    That said, the data above is taken from the IPCC FAR Fig 6, which used the simplified formulas given in Table 2.2 (page 52) to calculate forcings from concentrations.  The constants in those tables have been updated since then, based primarilly on the work of Myhre et al (1998).  In particular, the formula for CO2 has changes from 6.3*ln(CO2/CO2_initial) to 5.35*ln(CO2/CO2_initial).  To account for this, the 'actual' forcing should be increased by 18% for a true apples/apples comparison.  Alternatively, the projected forcings should be reduces by the reciprocal amount.  That gives us a current comparison of:

    BAU: 1.5 W/m^2

    B: 0.9 W/m^2

    D: 0.8 W/m^2

    Adjusted 'Actual': 0.91 W/m^2

    In 2010, the adjusted actual value was 0.74 W/m^2.  Therefore actual forcings are now tracking closer to scenario B than to Scenario D.  However, they are still tracking 40% below the BAU scenario.

    I have not been confident enough to attribute the best comparison to any scenario (and still am not), based on the differences between scenarios B through to D being to small at this stage relative to the error from pixel counting on a photocopied sheet from pages that were not always flat.  Actual forcings may be tracking as low as scenario D, or then again, they may be tracking higher than scenario B.  However, they are certainly not tracking as high as scenario A (BAU) - and are almost certainly tracking closer to B than to A (even if above B). 

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  49. Charlie A @47.

    You respond to TonyW@46 who was accusing "contrarians" generally of happliy "lying about the facts and, of course, cherry picking" as though your comment @42 were the target. This does raise the question as to whether you feel you are here to discuss/argue the science or simply here to argue the contrary position. Do be aware that the latter can very quickly lead to the insincere argument described by TonyW.

    Further in #47 you suggest there was "erroneous conversion from emissions to forcing" within the FAR scnarios. Could you expand on that comment? I would add that I recall the FAR scenarios did begin life by being roughly specified in terms of level of forcings by certain dates so the process of their creation could be considered strange. But "erroneous"?

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  50. Further to my post @48, based on Figure 9 of the IPCC FAR (below), the increase of temperture in 2015 relative to 1990 is 0.7 C for scenario A (BAU), 0.5 C for scenario B, and 0.4 C for scenario D.  These in turn correspond to trends of 0.26, 0.18 and 0.17 C/decade respectively.  The Gistemp trend from 1990 to current is 0.169 +/- 0.066 C per decade, ie, closest to scenario D but consistent with all scenarios except A.  The less than global HadCRUT4 trend is 0.155 +/- 0.066 C/decade, ie, slightly undershooting scenario D but again fully consistent with all scenarios except A.

    It becomes clear why Charlie A is so tenacious in insisting that scenario A is the only one that matters and the "IPCC prediction" despite the clear indication that it was relative to a particular scenario and other projections were also made.  Absent the absurd idea that BAU for 1990 was actually what happened, it becomes clear that the 1990 temperature projections stack up very well relative to observations.

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