SkepticblogSkepticblog logo banner

top navigation:

Consensus on Climate Change

by Steven Novella, May 20 2013

A recent review finds that over 97% of scientists believe that human activity is contributing to climate change. That is a very solid consensus of scientific opinion.

This, of course, does not mean that the consensus must be correct, but (along with other data) it makes it unreasonable to claim that there is no consensus, or that there is significant scientific controversy on this topic. In fact, the 97% figure exactly matches prior surveys. Many scientific organizations have also officially endorsed this consensus.

One of the common methods of deniers is to pretend as if there is a raging scientific controversy when in fact there is a solid consensus. Creationists, for example are constantly trying to portray evolution as a “theory in crisis,” when in fact it is doing quite well, thank you.

The study employed an interesting methods. They reviewed 12,000 peer-reviewed published papers on topics relevant to climate change. They then tabulated, for those papers in which the researchers expressed a clear opinion about climate change, whether or not they supported the conclusion of anthropogenic global warming. In over 97% of cases they did.

From the abstract:

We analyze the evolution of the scientific consensus on anthropogenic global warming (AGW) in the peer-reviewed scientific literature, examining 11 944 climate abstracts from 1991–2011 matching the topics ‘global climate change’ or ‘global warming’. We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming.

No survey is ever perfect – whenever you evaluate a subset of people in order to draw conclusions about the larger group, there is the possibility of selection bias. In this case one might argue that scientists who reject anthropogenic global warming are less likely to express those views in a peer-reviewed paper, or to have such views published.

This method, however, is reasonable. They also backed this up with another phase of the study in which they invited authors to rate their own research and opinions, and 97.2% endorsed the consensus of global warming. While it’s possible to quibble about this number, given the strong agreements among various methods around the 97% figure, it’s difficult to argue that the true figure is significantly different.

Why do we care about the consensus? Isn’t this just an argument from authority? Well, yes and no.

It seems reasonable, especially for those who consider themselves skeptics, to argue that facts and logic should determine a scientific question, not authority. Or that we should “let the facts speak for themselves.”

Unfortunately, facts cannot speak for themselves. Scientific evidence needs to be examined, rated for quality, interpreted, and put into a broader context. There is often no simple connect from facts to conclusions in science – background knowledge, knowledge of the processes of science, familiarity with critical thinking, logical pitfalls, and the effects of bias on interpretation are all necessary to come to a reliable conclusion about what those facts are telling us.

Different individuals are likely to have different biases and knowledge bases, and therefore may come to different conclusions about the same set of data. No individual, therefore, can be the ultimate authority on any scientific question.

The power of consensus is that individual quirks and biases will tend to average out. The consensus of scientific opinion, therefore, is a way to gauge the agreement and power of the scientific evidence.

The only other alternative is to evaluate all the scientific evidence first hand and come to your own conclusion. The potential pitfall here, however, is that individuals who are not experts in the relevant field believe that they can do this by examining secondary sources, such as popular writings on the topic. This is naive, however.

In order to really understand the evidence base for any scientific question you need to be able to read the technical literature first hand, and have a reasonable working knowledge of this literature. You then need to challenge your understanding of the evidence by discussing it with other experts, who may be familiar with evidence you missed, or have a perspective you do not. In other words – you have to engage intimately and extensively with the evidence and with the community.

In order to do this you pretty much have to be a full-time scientist focusing on the relevant area of study.

It seems absurd, when you really look at it, to substitute your own opinion based upon reading a smattering of simplified popular writings for that of the consensus of scientific experts who live and breathe the science.

What typically happens is that individuals who reject the consensus often come to the conclusion that science itself is broken. They reject science and the institutions of science, in order to justify their rejection of the particular consensus on which they disagree. Scientists, they believe, are therefore closed-minded, corrupt, or mindlessly follow the herd.

This is little more than ad-hoc special pleading, however (they are just making it up). Anyone who works with actual scientists would find such statements to be hopelessly out of sync with reality. Sure, there are individual scientists who are corrupt or closed-minded, but most vigorously defend their own intellectual independence.


For the average person (someone who is not a working expert in a particular field) the consensus of scientific opinion must be taken very seriously, and should not be casually tossed aside. In grappling with any scientific question, you should first try to understand what the scientific consensus is, how confident are scientists, is there any significant and viable minority view, and why scientists have come to that conclusion.

Humility and reason dictate that the consensus view should be given appropriate respect. I am not discouraging anyone from trying to understand the evidence first hand, in fact I recommend it. Learn and understand the primary evidence as much as your interest, time, and ability take you. Just be extremely cautious before you believe your opinions trump those of hundreds or thousands of working scientists.

With respect to anthropogenic global warming, there is a solid and confident consensus. You should be especially cautious of rejecting this consensus because it does not agree with your political world view.

135 Responses to “Consensus on Climate Change”

  1. d brown says:

    Back ion the 60’s it was known that the climate was leaving a long warm climate cycle and returning to normal. That’s cold, think of those old prints with sea water harbors froze over. In the early 70’s the build up of co2 was noted and people wondered what would happen with the cooling cycle as the heat was trapped. Now its known. It stopped the global cooling, but kept going. I think the cooling cycle messed up the first global warming predictions.

  2. Canman says:

    There is a consensus on CO2 causing global warming. Based on physics, it causes about 1.2 C per doubling. This is accepted by most serious climate sceptics on blogs such as WUWT and Climate Audit, along with lukewarmer blogs like Climate Ect. The supposed dangerous warming is caused by feedbacks which are not fully understood. These are things that the AGW proponents do not like to bring up.

  3. Ed Graham says:

    “One of the common methods of deniers is to pretend as if there is a raging scientific controversy…”

    Excellent example of the deniers lack of using scientific method.

  4. markx says:

    To keep things in perspective: In my opinion, most reasonable people (and scientists!) could not argue directly with any of Cook’s categories 2 through to 6 (below) (and noting my edited comments marked).

    Only Categories 1 and 7 (in my opinion) represent unjustifiable positions.
    Note his grouping of categories 1, 2 and 3 implies all are solidly endorsing a CAGW position.

    From the paper: Quantifying the consensus on anthropogenic global warming in the scientific literature Cook et al

    To simplify the analysis, ratings (below) were consolidated into three groups:

    1. Endorsements (including implicit and explicit; categories 1–3
    2. No position (category 4)
    3. Rejections (including implicit and explicit; categories 5–7).

    Original categories:

    (1) Explicit endorsement with quantification: Explicitly states that humans are the primary cause of recent global warming eg ‘The global warming during the 20th century is caused mainly by increasing greenhouse gas
    concentration especially since the late 1980s’

    (2) Explicit endorsement without quantification: Explicitly states humans are causing (‘some’ my edit) global warming or refers to anthropogenic global warming/climate change as a known fact: eg ‘Emissions of a broad range of greenhouse gases of varying lifetimes contribute to global climate change’

    (3) Implicit endorsement Implies humans are causing global warming: E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause ‘. . . carbon sequestration in soil is important for mitigating global climate change’ (lack of quantification, my edit)

    (4a) No position. Does not address or mention the cause of global warming.

    (4b) Uncertain Expresses position that human’s role on recent global warming is uncertain/undefined: eg ‘While the extent of human-induced global warming is inconclusive. . . ’

    (5) Implicit rejection. Implies humans have had a minimal impact on global warming without saying so explicitly E.g. proposing a natural mechanism is the main cause of global warming: eg ‘. . . anywhere from a major portion to all of the warming of the 20th century could plausibly result from natural causes according to these results’

    (6) Explicit rejection without quantification. Explicitly minimizes or rejects that humans are causing global warming: eg ‘. . . the global temperature record provides little support for the catastrophic view of the greenhouse effect’.

    (7) Explicit rejection with quantification: Explicitly states that humans are causing less than half of global warming: eg ‘The human contribution to the CO2 content in the atmosphere and the increase in temperature is negligible in comparison with other sources of carbon dioxide emission’.

  5. Daniel says:

    I don’t think even the folks labeled as skeptics like Watt and Lindzen, or fence sitters like Judith Curry, deny the basic premise of AGW. My understanding is that they take issue with the catastrophic predictions.

    • Max says:

      They’ve even denied GW, arguing that “the hockey stick is broken.”

      • Daniel says:

        That they may take issue with a particular hockey stick graph, doesn’t mean they dispute the basic premise. I’m pretty sure they don’t deny the basic premise.

      • Ichthyic says:

        pretty sure?

        you better look again.

        and again.

        and again.

        because they change their damn statements weekly.

        that’s why you shouldn’t even CARE what the AGW deniers think. Because they sure as hell don’t.

      • markx says:

        Daniel says: May 20, 2013 at 12:53 pm

        “… I’m pretty sure they don’t deny the basic premise…”.

        Most don’t, some do.
        Many simply dispute the need for immediate drastic action.
        And at the steady rate alarmists are rolling back their predictions, this is looking more likely to be correct.

        Trenberth has just written an article (warning us of global warming)predicting 30 cm of sea rise per century, a little better than Hansen’s 5 metres by the end of this century.

      • Max says:

        Trenberth is talking about the present and past rate since 1992, and Hansen predicted the future sea level by the end of this century.

      • markx says:

        Trenberth from above referenced article: …. Global sea level keeps marching up at a rate of over 30 cm per century since 1992 (when global measurements via altimetry on satellites were made possible), and that is perhaps a better indicator that global warming continues unabated.

        No need to discuss here the divergence between satellite data and tide guage data, but note tide guages record a steady 1.5 mm/year over 140 years with isostatic adjustment for deepening ocean beds of 0.3 mm/yr taken into account… So the average ‘nett’ sea rise is apparently about 1.2 mm/year … (unless you are on the sinking US central east coast, of course!)

        Trenberth sometimes quite honestly lays out uncertainties:
        Kevin Trenberth responds at Quark Soup.

        Concluding paragraph:

        So while their conclusions may be valid: yes there is no evidence of a discrepancy, given their uncertainties, and yes there is no “statistically significant” decline in OHC rates of change, but the uncertainties are so large that neither dataset is useful to know what is really going on, and that is the key point. The discrepancies among OHC data sets remain huge. We MUST do better. So the key point in their title is “within uncertainty”. It should add: “but the uncertainty is too large.”

      • tony duncan says:

        Since I have tentatively determined that you are acting the part of a denier, I will be scrutinizing your statements rather closely.
        your first two statements are quite reasonable and accurate.
        The rest of your comment is just assertions and mischaracterization.
        If you REALLY want to be considered a skeptic you have to look at the actual facts and determine as well as possible what the reality is.
        You state “And at the steady rate alarmists are rolling back their predictions, this is looking more likely to be correct.”
        That is obviously form the denier “Playbook” (your term re SkS). You do not back up the assertion and in my understanding of the state of climate science it appears clearly inaccurate and biased. I assume you are referring to the recent discussion about Climate sensitivity and to reducing the likelihood of the more extreme predictions of some ACC models.
        Fine tuning and reducing the uncertainty, even if only in one direction, is in no way rolling back. if you are referring to other issues I am unaware of please let me know. I am unaware of any scientist who has stated that CO2 doubling cannot be below 3°.
        Max clarified the Trenbeth thing for you and your response to that is quite inadequate and un-sceptical. You seem to be implying that there is no reason to believe that sea level rates will increase in this century. But since you are being ambiguous, (a tactic deniers use constantly) it is hard to tell what you are actually saying here.
        And the major problem, of course is with Hansen’s statement. As is typical with denier’s you take his 5 meter remark so far out of context, that it borders on being a flat out lie. Let me state that I disapprove of what he said, EXACTLY because people like you would totally distort the meaning. MAybe you are just being naive and believing denier talking points about this statement, but as a skeptic I looked it up to see what he actually said.
        I am not looking it up right now, but the gist was that he was extremely frustrated with deniers contending sea levels would not rise very much, and it would not be an issue. He said that while there was NO scientific basis for the claim, that sea level COULD rise 5 meters in the next century. That it was physically possible, and that it was just as likely as sea levels rising only 10cm ( not sure of the exact number here). There is absolutely nothing wrong with what he said, EXCEPT he should have known that it would be misused by deniers.
        The point is that this comment makes me seriously question your interest in the truth.

      • markx says:

        Hansen and 5 metres: Repeated it in his most recent paper. See Fig 7 and comments below. Throws in the odd ‘preposterous’ but keeps explaining how possible it is.

        Alley (2010) reviewed projections of sea level rise by 2100, showing several clustered around 1 m and one outlier at 5 m, all of these approximated as linear in his graph. The 5 m estimate is what Hansen (2007) suggested was possible under IPCC’s BAU climate forcing.

        Such a graph is comforting – not only does the 5-meter sea level rise disagree with all other projections, but its half-meter sea level rise this decade is clearly preposterous.

        However, the fundamental issue is linearity versus non-linearity. Hansen (2005, 2007) argues that amplifying feedbacks make ice sheet disintegration necessarily highly non-linear, and that IPCC’s BAU forcing is so huge that it is difficult to see how ice shelves would survive.

        As warming increases, the number of ice streams contributing to mass loss will increase, contributing to a nonlinear response that should be approximated better by an exponential than by a linear fit. Hansen (2007) suggested that a 10-year doubling time was plausible, and pointed out that such a doubling time, from a 1 mm per year ice sheet contribution to sea level in the decade 2005-2015, would lead to a cumulative 5 m sea level rise by 2095.

      • tony duncan says:


        you need to actually read the paper. it makes a lot of sense. Tht does not mean it is correct, but I see nothing unscientific in it. He is describing a situation that is possible in terms of physics, and with a continuing increase of CO2 emission through the end of the century. He says that we do not understand the nature of ice sheet melting in a situation with such extreme increases in temperature, and he included relevant negative feedbacks that would limit it even then.
        He DOES say that multiple meter rise is realistically possible under that scenario. A scenario where there is NO change in the emissions of CO2 throughout the 21st century.

        It seems clear that, like deniers, you are not interested in describing what scientists are actually saying. I like how you dismiss HIS terming of it as “preposterous” when what he is actually saying is that a linear increase toward 5 meters was preposterous as projected in Allen’s graph. and it is totally consistent with the talk I heard where he complained that 5 meters was as likely as 10CM.
        Please point out where Hansen’s science is incorrect. I may be wrong but it makes perfect sense to me that ice loss from Antarctica and Greenland are MUCH more likely to be non linear than linear.
        I personally think that a 2 meter rise is extremely unlikely and I even doubt a 1 meter change, because as soon as it becomes clear that such an outcome is likely there will be a tremendous effort to stop the cause of it.

        At LEAST you did post something that was accurate. however it totally confirms the point that I was making. You writing that Hansen says there will be a 5 meter rise in sea level is so far out of context as to constitute being a lie. the fact is that he made an extrapolation of what MIGHT be possible considering uncertainty leading to the worst physically possible result from the worst possible scenario.
        That said I do NOT agree with his even making this sort of statement because politically he knows that anything he says is going to be distorted by people with no interest in the truth. He appears not to care, and I think that is a big mistake. the same is true about his runaway greenhouse effect. What he actually says is conceivable because of the limits of uncertainty in numerous factors. But his enemies only care about painting him as a crazy fanatic. What he is is a frustrated advocate who doesn’t understand why nothing is being done to something he rightly considers to be potentially a hugely serious problem. Unfortunately his words are ALSO twisted by fanatic alarmists as well, and that does no one any good either.

      • tmac57 says:

        Tony,I agreed with most of your comment,but I have some doubts about this:

        I even doubt a 1 meter change, because as soon as it becomes clear that such an outcome is likely there will be a tremendous effort to stop the cause of it.

        If it ever becomes evident that such an outcome is likely to everyone (not just those paying attention now) then I suspect that we will be committed to that much sea level rise and more,due to the long lived nature of CO2 in the atmosphere,and the difficulty in turning such a huge ‘ship’ around in the time required in order to avoid a ‘collision’.
        I will repeat this as long as it takes for those who don’t quite get it:
        “Uncertainty is not your ally when it comes to risk assessment.You need to take a realistic look at the full range of outcomes,and the error bars associated with those risks.And to bet on double zero to save your life just because it is within the range of possibilities,is just as foolish as betting against it coming up.”

      • tony duncan says:


        Maybe “Doubt” was too strong a term. I think it is quite possible that there will be a 1 meter rise because of the point you make. And actually Hansen’s paper makes a strong case for the difficulty of preventing major changes if one waits until there is conclusive confirmation of factors that have geometric results.

  6. markx says:

    And note this new (slightly less alarming) paper (be nice to see an article on this):

    New Nature Geoscience paper (2013) “Energy budget constraints on climate response” Otto et al doi:10.1038/ngeo1836 Published online 19 May 2013

    …..predicts just 1.3C temp rise by 2060, half of which has happened already…..

    …the authors include fourteen climate scientists, well known in their fields, who are lead or coordinating lead authors of IPCC AR5 WG1 chapters that are relevant to estimating climate sensitivity. Two of them, professors Myles Allen and Gabi Hegerl, are lead authors for Chapter 10, which deals with estimates of ECS and TCR constrained by observational evidence. The study was principally carried out by a researcher, Alex Otto, who works in Myles Allen’s group.

    • tony duncan says:


      and how is this paper outside the consensus position of ACC?
      And related to your above comment regarding sea level. Do you believe a .5 increase in temps in the next 30-40 years will somehow NOT lead to an increase in sea level rise?

      • markx says:

        Surely it is all a question of severity and whether there is a need for immediate action ‘before it’s too late!’

        I can picture someone like you observing a final total 0.5 C of temperature rise and a final total of 10 cm of sea rise by 2100 and proclaiming “See! I was right all along, and what’s more, I’m sure it was mainly anthropogenic!”, while around you the world continues to function normally.

      • tmac57 says:

        And why would 2100 be some magical stopping point for warming and sea level rise,especially if the world in the next 87 years follows your advice to proceed slowly with CO2 mitigation,or falls prey to Inholfe et al’s belief that this is the “greatest hoax” ever perpetrated on the world,that more CO2 is plant food and is thus harmless and good,and no action is taken?
        A BAU scenario for CO2 rise will be an unmitigated (literally) disaster by 2100 and beyond certainly.

      • tony duncan says:


        you are absolutely wrong about my reaction. Maybe you don’t believe me that I am actually interested in understanding reality as opposed to winning arguments. If the results are as you say, I would acknowledge that I had been completely wrong. the IPCC had been completely wrong,and that ACC theory had serious flaws that were not adequately understood by climate scientists. That is of course possible. I would want to know WHY the theory was so wrong and if indeed people who I had called deniers had been correct.I would have a lot of apologizing to do.

      • markx says:

        Well, I respect you for saying that.

        So far there is nothing to apologize for, the world is still in a state of discussion rather than action.

        Interestingly, if all the alleviation mechanisms were suddenly dropped into place, and the temperature did not rise, it may be difficult to know whether they’d been effective or whether all was still in the range of natural variation.

        My position is ‘they’ are nowhere near as sure of the mechanism and the degree of effect as has been stated and take little account of the likelihood of self regulating feedbacks.

        ‘they’ also overstate the accuracy of past and current measurements and downplay the multiple assumptions, adjustments and algorithms that are applied to extract things such as satellite measured sea level rise and ocean temperatures.

        I would be very surprised if temperature rises reached 2 degrees C or sea rises exceeded 15 cm, and would also be surprised if that proved to be catastrophic on any significant scale.

        If these events were to be as severe as has been stated, I then would have to apologize for questioning the current state of their science and knowledge.

      • tony duncan says:

        those all sound like positions I disagree with but you are certainly free to have them.

        As i said i know some climate scientists and form what I have read, i am much more confident of their level of understanding than you

      • markx says:

        I do expect we will know here this is all heading within the next 20 years – the real extensive monitoring operations have just begun.

      • tony duncan says:

        I agree,

        But I would actually be surpised if we don’t have a pretty clear idea in the next 10 years.

  7. Canman says:

    The public has a right to be skeptical of experts in any field, from Robert McNamara’s whiz kids to the FOIA dodgers at CRU. Even climate scientists have their own self interest. In fact, with them it’s especially so. While they may not make as much money as Jim Hansen, their funding depends on how serious the public takes AGW. They also have an intangible interest in being saviors of the world. I would guess that most of them have a left wing bias towards more statism and government control of everything. This is area where people who call themselves skeptics show conspicuously little skepticism. We have bankruptcies at sexy green photoop boondoggles like Solyndra and A123. There’s the perverse spectacle of solar leader Germany closing its carbon free nuclear plants and building especially dirty brown coal plants. The wind industry is getting a free pass on killing bats and endangered raptors.

    • Max says:

      “The public has a right to be skeptical of experts in any field”

      More in politics, economics, and technology forecasting than in science.

      “We have bankruptcies at sexy green photoop boondoggles like Solyndra and A123.”

      So what? Did the climate scientists work for them?

      “The wind industry is getting a free pass on killing bats and endangered raptors.”

      Aww, crocodile tears.

      • Canman says:

        Thanks for the link Max. Somehow I missed that Dunning post. It had interesting discussion, but not much on hawks and eagles, which seem like they would be more vulnerable to wind turbines. I don’t think they are being decimated by windows and house cats.

    • Ichthyic says:

      “hile they may not make as much money as Jim Hansen, their funding depends on how serious the public takes AGW. ”

      actually, that’s isn’t correct at all. There has not been significant growth in any related science funding.

      if the topic wasn’t AGW, scientists interested in how climate works would, and of course do, look at other things.

      so you can stop lying, or flaunting your ignorance. whichever.

  8. Nyar says:

    “Why do we care about the consensus? Isn’t this just an argument from authority? Well, yes and no.”

    Actually, just yes.

    “It seems reasonable, especially for those who consider themselves skeptics, to argue that facts and logic should determine a scientific question, not authority. Or that we should “let the facts speak for themselves.””

    Yes we should.

    • Max says:

      Facts don’t interpret themselves. If you reject the scientific consensus in favor of your own conclusion, then you’re assuming that your interpretation is better than theirs, which isn’t likely.

      • Nyar says:

        I would assume that I don’t need to explain why avoiding a recognized logical fallacy is desirable. The evidence itself is important, the consensus is not.

      • Max says:

        The consensus of experts who understand the evidence is more important than the conclusion of a layman who doesn’t understand the evidence.

      • Nyar says:

        I don’t think so. The consensus of experts and the conclusion of the layman are equally unimportant. Only the evidence itself is important and that is all that we as skeptics should be considering.

        Should we accept the consensus of Theologians about whether a diety exists?

      • Max says:

        Skeptics apply the baloney detection kit to figure out which sources are reliable and which aren’t. It won’t tell you which scientists are right or wrong, but it’ll tell you if someone isn’t even doing science.

      • Nyar says:

        Right! Here is Carl Sagan’s BDK:

        The following are suggested as tools for testing arguments and detecting fallacious or fraudulent arguments:

        Wherever possible there must be independent confirmation of the facts
        Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
        Arguments from authority carry little weight (in science there are no “authorities”).
        Spin more than one hypothesis – don’t simply run with the first idea that caught your fancy.
        Try not to get overly attached to a hypothesis just because it’s yours.
        Quantify, wherever possible.
        If there is a chain of argument every link in the chain must work.
        “Occam’s razor” – if there are two hypothesis that explain the data equally well choose the simpler.
        Ask whether the hypothesis can, at least in principle, be falsified (shown to be false by some unambiguous test). In other words, is isttestable? Can others duplicate the experiment and get the same result?

      • Max says:

        “The consensus of experts and the conclusion of the layman are equally unimportant. Only the evidence itself is important and that is all that we as skeptics should be considering.”

        You ARE a layman. Your conclusion after considering the evidence IS the conclusion of a layman. It takes some humility to defer to the experts.

      • tony duncan says:


        as there is NO testable theory of that does NOT involve CO2 having a significant role in climate that has survived scrutiny, ACC being the only game in town.
        While the issue has become extremely politicized I see no aspect of Sagan’s rules that are not being followed in the science. In fact because it is SOP p[politicized and so many ridiculous claims have ben made against it there has been more scrutinizing of more aspects than any other science, more than even evolution I would guess.
        The politics certainly affects the science and there are certainly mistakes, but the idea that it is still so completely accepted is a testament to the validity in my view

    • Max says:

      The argument from authority is only wrong if the authority is no more likely to be right than anyone else or if the premise is that the authority can’t possibly be wrong.

      • Nyar says:

        I disagree. The agrument from authority is wrong because conclusions should be based on evidence not on the word of an authority figure, even if they are likely to be right.

      • Max says:

        The bottom line is what’s more likely to be right, your own independent interpretation of the evidence or that of the “authority” figure.

        Of course the “authority” we’re talking about here isn’t “power to enforce laws” but “expertise.” If you call it the argument from expertise, it doesn’t sound like a fallacy.

      • Nyar says:

        Call it what you like, it is still a textbook example of a logical fallacy.

    • Daniel says:

      In other words, argument from authority is ok except when it isn’t.

    • tmac57 says:

      Nyar,your responses on this thread show that you absolutely do not understand the argument from authority.
      I would point you to some sites that discuss and define informal fallacies,but then of course you would reject those as arguments from authority.

      • Nyar says:

        Then Steven must not understand it either since he mentioned in the post that it is (and is not) an arguement from authority.

        Maybe you would like to point out exactly how we got it wrong.

      • tmac57 says:

        An argument from authority isn’t automatically considered fallacious.
        When the expert is qualified in the field for whatever the claim is,is not biased by external pressures (EX:overriding financial/political pressures),is part of a consensus of other qualified experts in the field related to the claim,then that holds as a valid appeal to authority.
        When the expert’s (or non-expert) field of study is outside that of the claim, and/or they are demonstrably biased,or are significantly outside consensus opinion of other experts in the relevant field,then appeal to that authority is fallacious.They may not necessarily be wrong,but the appeal to their expertise should be considered questionable.

      • Nyar says:

        I disagree. The appeal to authority is always fallacious even if as you point out the ones making the appeal are right. The reason to accept the claims made by experts is because the claims are supported by the data, not because they are experts. Likewise people who not experts can and do make claims that well supported by data. Using the appeal to authority is just lazy and sloppy, and anyone calling themselves a skeptic should reject it in favor of the actual data.

      • tmac57 says:

        Sorry Nyar but you don’t get to win a dispute by redefining terms that have been in use for hundreds of years,just to fit your argument:

        Read and comprehend:

      • Nyar says:

        This is from your first link:

        “It is unnecessary. If a question can be answered by observation or calculation, an argument from authority is not needed. Since arguments from authority are weaker than more direct evidence, go look or figure it out for yourself.”

        Clearly, I am not redefining anything. Why are you (plural) insisting that we must accept this particular fallacy with respect to global warming? Is it some kind of left-wing thing that I just don’t understand?

      • Max says:

        Nyar, if your child is sick, do you ignore everything the doctors say and diagnose the child yourself?

      • Nyar says:

        No. But I do require the doctor to explain to me what he or she believes is wrong. If the doctor says that a layman like me cannot understand and that I must just accept his or her diagnosis, then I find another doctor.

      • Max says:

        What if the doctor is just following medical guidelines that summarize the scientific consensus?

      • Nyar says:

        What if? I am looking at the facts that the doctor presents to support the diagnosis. If the doctor won’t give any any supporting data but just says that I should trust him or her because they are a doctor, then that is a red flag for me. I will seek out a different doctor who will provide some data.

      • tony duncan says:


        you just gave a very good point. If you can find a climate scientist who tells you ACC means global temps will increase from 2-5°C in the next century and they do not provide you with clearly understood reasoning that is backed up by facts that can be explained in layman terms, then I would agree that you should get another opinion
        However if the scientist gives you that info and someone on the street tells you that it is not going to happen, and they give you explanations that SOUND scientific, and you just accept that, you are NOT being skeptical.
        If almost every scientist tells you very similar things, and you keep getting people on the street that tell you the scientists are wrong, but they give you very different reasons, and you decide to believe the people on the street, you are not being skeptical.
        It is NOT an appeal to authority if the authorities give reasonable explanations and they can show that those opposing their position are giving unreasonable explanations. that does NOT mean that it is absolutely certain the authorities are right, but basing decisions on those experts is not acting solely from authority.

    • Cameron says:

      Nyar, you seem to clearly understand the concept of logical fallacy in its most literal usage, but you don’t seem to be skeptical of your own use of this definition. Would it be reasonable to understand that the “appeal to authority” is mitigated by circumstance? For example, if you go to a doctor and your doctor says you have condition A & B, the doctor is appealing to the consensus and authority of over a hundred years of medical research. The doctor obviously didn’t perform his/her own tests to validate every item that indicates a specific condition. The point I am trying to make is that you are being far to rigid and literal with pinpointing logical fallacies.

    • Ichthyic says:

      “Actually, just yes.”


      it’s not authoritarian when those same scientists have all actually looked at the data themselves, independently, and all drawn the same conclusion.

      you don’t know what you’re talking about.

  9. David says:

    The study is hopelessly biased, as you hint at, Dr Steve. It only gauges the opinion of publishing climatologists, completely excluding the Big Fossil-funded physicists and economists who don’t publish climate research. For balance, someone should audit Fox News segments during the same period.

    • markx says:

      You may mean ‘hopelessly broad’ and actually a little bit vague in conclusion.

      I myself would give a “yes” to a statement like ‘Emissions of a broad range of greenhouse gases of varying lifetimes contribute to global climate change’ as in Cook’s category 2 …(Endorsements (including implicit and explicit; categories 1–3)

      And … he’d take that as a “Yes” and a strong endorsement of … um … climate science? … or of a looming catastrophe? …or as agreement on a call to immediate, world wide emergency action?

      • Max says:

        If you add “…the global temperature record provides little support for the catastrophic view of the greenhouse effect,” that’s under #6.

        Not sure what happens if you say both things, as in, “Emissions of a broad range of greenhouse gases of varying lifetimes contribute to global climate change, but the global temperature record provides little support for the catastrophic view of the greenhouse effect.”

      • markx says:

        Max says:
        May 21, 2013 at 2:38 am
        Not sure what happens if you say both things, as in, “Emissions of a broad range of greenhouse gases of varying lifetimes contribute to global climate change, but the global temperature record provides little support for the catastrophic view of the greenhouse effect.”

        Perhaps a fair statement given the more recent publication mentioned above:

        Nature Geoscience paper (2013) “Energy budget constraints on climate response” Otto et al 19 May 2013

        …..predicts just 1.3C temp rise by 2060, half of which has happened already…..

      • tony duncan says:

        So Markx, are you accepting this study uncritically? have their been any analysis of this study?
        Do the conclusions of the study support the consensus position?
        What are the possible consequences if the conclusions are valid?
        Are their factors that the study does not take into account?

        I certainly see no reason at all to dismiss the conclusions, but before I would take this as the gold standard in the last word on the effects co ACC i would want to wait a little and see what the responses are to it.

      • tmac57 says:

        Tony,read what Myles Allen,co-author of the paper wrote in the Guardian:

        Uncertainties are no reason to celebrate

      • markx says:

        Tmac, intersting article: But Myles Allen is hardly putting up a very convincing technical defense here for the dramatic (and false) media onslaught we have experienced with talk of Frankenstorms, droughts, fires, ‘weather on steroids’, etc:

        Blockquote>Is Ridley right that there is no actual evidence of harm as long as droughts, floods and storms are within historic variability? Try explaining to a casino bouncer that it doesn’t matter you are using loaded dice because a triple-six is within historic variability – but that is a different story.

      • tony duncan says:


        I read that article, thanks. it is kind of what I wrote to Markx in a comment, that if Skeptics are accepting this, which is in the range of the consensus, then it is skeptics who are rolling back their claims not climate scientists.
        I alos read Curry’s take on Allen, and as is sometimes the case, she perplexed with her grasping at this as if it is some sort of proof that supporters of ACC have been wrong all along and SHE has been right WTF??
        Not sure what MArkx is suggesting in his comment below yours. It seems clear to me that if Sandy or Irene happen every 5 or ten or even 20 years, then arguing that some of the largest storms ever recorded in that location happening at a frequency never seen before is not a problem because it is possible with natural variability, will not be a popular political position to take.

      • markx says:

        Sure, if Sandy or Irene were happening every 5 or 10 years you would have everyone’ attention…

        But they ain’t.
        And it is a straight falsehood to proclaim those events as any sort of proof of anything. And holding them up as ‘examples of what will happen’ is marketing and simply meaningless.

    • Ichthyic says:

      “or balance, someone should audit Fox News segments ”


      right. Next you’ll be telling us to really learn about democracy in the US, we should be reading Pravda.

    • Ichthyic says:

      “The study is hopelessly biased, as you hint at, Dr Steve. It only gauges the opinion of publishing climatologists”

      do you clowns actually expect just making shit up on the fly is going to get people to listen to you?

      hell, if you JUST CLICK THE LINK, you can immediately see that this is NOT the case.

      do I need to quote it for you, to prove you are a lying moron, or do you just want to just retract what you said?

  10. d brown says:

    Look this war is a is a matter of winning politics to the right wing. Its part of their war for power and they must win. Its a point that must be beaten or the right loses. Its based on politics and fact matters not.

    • Canman says:

      “Its part of their war for power”

      No, it’s a war against bloated government power.

      • d brown says:

        No, it’s a war against any government. a government with the power to tell the rich what not to do.

      • tony duncan says:


        that certainly is the argument. the problem is that if the science is correct then bloated government will be a footnote in a hundred years.
        Of course from a realistic view , a real conservative would see ACC as a great argument against bloated government. If this is a serious problem and it clearly might be, then that is a strong argument for making government much more efficient reducing government expenditures in areas that are ineffective and overblown ( I e the nonexistent soviet threat that requires the largest military almost as large as the entire rest of the world), and working with industry to solve the problem in the way that helps government and industry and consumer/citizens in ways that maintain quality of life and consider international factors in a rational approach to decreasing carbon emissions and mitigating effects before they become serious.

  11. Eddie Scott says:

    I’m in complete agreement with the scientific consensus on this, BUT… I am not at all comfortable that this study, as quoted, supports the statement that 97% of “scientists” (note the lack of qualifiers) believe that human activity contributes to climate change.

    The excerpt quoted says that “66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global climate change.

    As I read it, they are saying that 97% of the 32.6% of scientists who took a position on AGW (31.6% of all scientists who published) agree that human activity contributes to climate change. Thats a very strong statement, but you cannot then assume that that 31.6% of scientists is exactly representataive of all scientists, not even all scientists that have published studies on climate change (since 2/3s of the studies didn’t take a position on the subject).

    I do believe there is a strong scientific consensus on the issue, but I do not think we are justified in quoting this 97% number as if it is good science, at least not based on what is published here.

    • laursaurus says:

      The science of cherry-picking?

    • tony duncan says:

      That seems like a reasonable point, but the authors have addressed the issue in a reasonable way. But your point does add a level of uncertainty that is worth considering

  12. BillG says:

    Great! The consensus is solid and finally the matter is settled.

    Wait, now what??

    • laursaurus says:

      We’ve heard this scientific consensus argument since Al Gore made his Hollywood Blockbuster.
      We a need a study that identifies why the public isn’t motivated by this tired talking point.
      Maybe if a real solution like nuclear and natural gas power instead of coal would be more feasible than carbon taxes or Cap & Trade schemes. The public just isn’t buying the consensus as a good enough reason to adopt meaningless mitigation solutions.

  13. markx says:

    Aaaand of course we have a few dissenters regarding Cook’s classification of their papers:

    Idso was asked:”Is this an accurate representation of your paper?”:

    ‘Ultra-enhanced spring branch growth in CO2-enriched trees: can it alter the phase of the atmosphere’s seasonal CO2 cycle?‘ is categorized by Cook et al. (2013) as; “Implicitly endorsing AGW without minimizing it“.

    Idso: ‘Ultra-enhanced spring branch growth in CO2-enriched trees: can it alter the phase of the atmosphere’s seasonal CO2 cycle?‘ is categorized by Cook et al. (2013) as; “Implicitly endorsing AGW without minimizing it“.

    “That is not an accurate representation of my paper…… other literature had previously claimed a measured advance was due to rising temperatures, but we showed that it was quite likely the rise in atmospheric CO2 itself was responsible …… It would be incorrect to claim that our paper was an endorsement of CO2-induced global warming.”

    Another dissenter was Scafetta, who has a good point to make:

    Scafetta: “Cook et al. (2013) is based on a strawman argument because it does not correctly define the IPCC AGW theory, which is NOT that human emissions have contributed 50%+ of the global warming since 1900 but that almost 90-100% of the observed global warming was induced by human emission.

    There are some others:

    • tony duncan says:


      once again using WUWT as a source without bothering to look for responses to their analysis is anti-skepticism. there are so many mischaracterizations distortions and pretty much outright lies on that site that any reasonable person would check before posting what they write. just their posts on Marcott recently make it clear to me that their interest is ONLY in knocking down ACC in any way possible.
      I have read the responses and they make VERY good points.

      • markx says:

        Oh, thanks for reminding me, I missed a few Tony…

        Here is a Twitter exchange with a very dissatisfied Richard Tol (very much an AGW supporter) trying to get some sense out of Nuccitelli (bolding mine):

        1. Richard Tol @RichardTol
        The Cook paper comes further apart
        7:01 AM – 21 May 13

        2. Dana Nuccitelli @dana1981
        @RichardTol You might want to actually read our paper before claiming it’s ‘coming apart’ based on ignorant and wrong claims.
        10:22 PM – 22 May 13

        3. Richard Tol @RichardTol
        .@dana1981 Don’t worry. I did read your paper. A silly idea poorly implemented.
        10:48 PM – 22 May 13

        4. Dana Nuccitelli @dana1981
        @RichardTol Have to say I’m disappointed. Didn’t have you pegged as a denier before. Fine to dislike our paper, but don’t lie about it.
        11:04 PM – 22 May 13

        5. Richard Tol @RichardTol
        .@dana1981 I published 4 papers that show that humans are the main cause of global warming. You missed 1, and classified another as lukewarm
        11:31 PM – 22 May 13

        6. Richard Tol @RichardTol
        .@dana1981 I published 118 neutral (in your parlance) papers. You missed 111. Of the 7 you assessed, you misclassified 4.
        11:40 PM – 22 May 13

        7. Richard Tol @RichardTol
        .@dana1981 Most importantly, consensus is not an argument.
        11:41 PM – 22 May 13

        8. Richard Betts ‏@richardabetts
        @dana1981 Not that I approve of “Denier” but @RichardTol isn’t one anyway. We publish together … and he’s an IPCC CLA
        1:59 AM – 23 May 13

        9. Dana Nuccitelli @dana1981
        @richardabetts @richardtol is behaving like one, RTing Marc Morano’s Climate Depot and misrepresenting our paper.
        6:37 AM – 23 May 13

        10. Richard Tol @RichardTol
        @dana1981 In what way did I misrepresent your paper?
        7:33 AM – 23 May 13

        11. Richard Betts ‏@richardabetts
        @dana1981 How is Denier defined? What is being denied? Can someone be in the 97% who accept AGW and still be a denier?
        8:12 AM – 23 May 13

        12. Dana Nuccitelli @dana1981
        @richardabetts Broadly speaking, one who encourages Morano, Watts, and Poptech behaves like a denier (not necessarily same as denying AGW)
        8:14 AM – 23 May 13

        13. Dana Nuccitelli @dana1981
        @RichardTol Abstract ratings and author self-ratings based on full papers are two distinct parts of our study, for one.
        8:15 AM – 23 May 13

        14. Richard Tol @RichardTol
        @dana1981 When did I say they are the same?
        8:29 AM – 23 May 13

        15. Richard Betts ‏@richardabetts
        @dana1981 So basically this is politics then.
        8:40 AM – 23 May 13

        16. Dana Nuccitelli @dana1981
        @richardabetts No, it’s half misrepresenting our paper, half encouraging deniers to do the same.
        8:47 AM – 23 May 13

        17. Dana Nuccitelli @dana1981
        @RichardTol You’ve said we misclassified your papers. We didn’t classify them at all, we rated the abstracts, invited you to rate the papers
        8:49 AM – 23 May 13

        18. Richard Betts ‏@richardabetts
        @dana1981 I meant “denier” seems to be a political label – not talking specifically about Richard T’s views on your paper.
        8:54 AM – 23 May 13

        19. Richard Tol @RichardTol
        .@dana1981 Semantics. You misrated my papers. When did I lie, what did I misrepresent?
        9:46 AM – 23 May 13

        20. Dana Nuccitelli @dana1981
        @RichardTol It’s not semantics at all. You’re equating two different things which we evaluated separately.
        10:06 AM – 23 May 13

        21. Richard Tol @RichardTol
        .@dana1981 Not at all. You generated data. The data that I understand are all wrong. The errors are not random. But now tell me about my lie
        10:17 AM – 23 May 13

        22. Richard Tol @RichardTol
        @dana1981 You accused me of lies and misrepresentation. Would you care to elaborate cq withdraw your accusations?
        11:05 AM – 23 May 13

        23. Dana Nuccitelli @dana1981
        @RichardTol I already elaborated twice. On top of the abstract/paper issue you suggested it was a fault our sample only included 10 of yours
        12:14 PM – 23 May 13

        24. Richard Tol @RichardTol
        @dana1981 I think your data are a load of crap. Why is that a lie? I really think so.
        12:49 PM – 23 May 13

        25. Richard Tol @RichardTol
        @dana1981 I think your sampling strategy is a load of nonsense. How is that a misrepresentation? Did I falsely describe your sample?
        12:50 PM – 23 May 13

  14. Max says:

    What if the abstract says something like, “The IPCC says global warming during the 20th century is caused mainly by increasing greenhouse gas
    concentration.” By accepting the consensus without actually researching it, does it increase the consensus?

  15. KLG says:

    Let me say that I agree with Eddie Scott’s point above and have made that same point in several other places in the last few days.

    Nearly every scientific principle you can think of has its detractors.
    There are people with PhDs who think the Sun is powered not by fusion, but by electricity.
    There are people with PhDs (a few of them actually legitimate) who think the Earth is only 6,000 years old.
    There are people with PhDs who think the Earth does not move; rather it is stationary at the center of the universe, does not orbit the sun, and does not revolve around its own axis.
    There are people with PhDs who think HIV does not cause AIDS.

    The mere fact that there are a few people who reject AGW doesn’t imply there is a “controversy.” Otherwise, we could argue that all of science is a controversy.

    Public responses to scientific findings should be based on consensus. People outside science should realize that they are not scientists – and for the most part have a cartoon understanding of the evidence, but also of what science is and how it works.

    The fact that science is sometimes overturned does not justify ignoring the actual evidence that we already have. If the potential for future disproof were an argument against AGW, then we would have to reject all of science by the same criterion.

    • tony duncan says:


      I agree in principle and in practice with a few caveats.

      ACC is an incredibly politicized issue with profoundly impactful consequences. In that sense I believe it requires much more scrutiny than most other scientific theories.
      it is reasonable to bring in political considerations, And to question the factors that might bias scientists. they are human and there are issues of pride and lack of humility. these are all issues that deniers bring up. Unfortunately the deniers themselves are so fanatic that they are unwilling to accept any result other than that ACC is wrong and therefore are willing to invent, fabricate distort and basically cheat in order to achieve their goal.
      This creates a dangerous dynamic because the deniers have so much political power. It can lead to supporters of ACC cutting corners or exaggerating, which the deniers immediately jump. Because the science is complicated it is not hard to spin science in ways that are designed to fit an agenda rather than provide a clearer look at the issue.
      it helps that I know some climate scientists and have been able to question them first hand about valid questions. having always been dealt with respectfully and never been given false information by them, I am much more comfortable accepting their responses in cases where I do not understand the science

  16. Gwenny says:

    And what do they suggest we DO? Because I never see anyone suggesting we make real changes. It’s all about somehow STOPPING millions of years of climate cycling and not adapting. We can’t STOP climate change. IF we manage to rein in our contributions, the climate will continue to change. The next Ice Age will start. And then where will we be . . well, the folks alive today won’t notice much. As the glaciation part of the cycle is 90,000 years and we won’t live to see it get to it’s peak. But we have never lived through a glaciation as a society. Our culture is less than 10,000 years old . . or about the time that the current interglacial period has lasted.

    I have no doubt the climate is changing. This is something I have believed for decades . . even before this whole AGW thing got going. To deny that the climate is changing is silly. But to claim it is, and we are causing it, and yet to have NO EFFING IDEA what we can do about it . . .makes me ill.

    We have the tech to not only adapt to any climate change, we have the tech to make sure the surplus of food gets to the hungry. We have the tech to build beautiful cities with space for everyone. It’s time we stopped being jerks and started looking for solutions.

  17. markx says:

    More on Cook et al classification issues:

    Note he had 7 categories, which were then rolled into 3 categories
    1. Endorsements (including implicit and explicit; categories 1–3
    2. No position (category 4)
    3. Rejections (including implicit and explicit; categories 5–7).

    Brandon Shollenberger (Comment #113188) May 17th, 2013 at 2:13 am (on degree of AGW responsibility for warming).

    The top category (1) covers everything from 50% to 100%.
    The other top categories (2 & 3) cover everything from 0% to 100%.
    The bottom categories (5 to 7) cover from 0% to 50%.

    Note; also according to Shollenberger only 65 of 12,280 papers (he extracted) fell in the top category.

    • markx says:

      more from

      Brandon Shollenberger (Comment #113191)
      May 17th, 2013 at 2:50 am

      This study found ~4,000 (of THE 12,000 plus surveyed)
      abstracts that say humans cause some amount of global warming. Only 143 of those indicate how much warming humans are responsible for.
      Of those, 65 say its a lot, 78 say it isn’t much.

      • tony duncan says:


        Once again your source is not someone I would trust. Have you looked at the responses to his points?

        As with the Lewandowsky case, I do not doubt that there are specific issues with the study. But to me it is like saying that Marcott is worthless because the proxies for the 20th century suck.
        If you read the emails that Lucia posted, I see absolutely NO attempt by the people putting the study together to make some sort of nefarious inaccurate conclusion to promote their fraudulent claim.
        If you studied the issue and look at all the research done in climate science there is no question that the overwhelming number of scientists involved support the idea that ACC is a significant factor in current and future climate. On the other hand there is a clear motivation by deniers to find ANYTHING wrong with the study to discredit it.
        If you read the fuss around Toll it becomes pretty clear that it is a rather foolish and desperate attempt, and not a genuine desire to discern reality.

      • markx says:

        I think Marcott is a very valuable paper, albeit marred by the artifacts which created an erroneous 1950s uptick.

        Interesting in that it indicates perhaps 25% of the early Holocene was warmer than we are today.

      • tony duncan says:


        why do you say “marred”? the paper was not about current temps, and they clearly express the view that proxies are not worth much for assessing current temps, and it is all rather moot since there are temp records. They included them because they were there, and no reason not to include them this is the type of thing that makes me wonder what the motivation is for making a statement like that.
        There is nothing particularly interesting about their results for the early holocene. they are quite in line with other reconstructions for the time period, and I have never seen any climate scientist claim otherwise. Certainly for the future most predict that in the next hundred years we will have temps higher than any seen in the Pleistocene.

      • markx says:

        Interesting to note that in Marcott’s PhD paper (largely the same data) the 20th Century ‘upticking proxies’ were not present.

        In later discussions Marcott conceded this extra later data in shown in the publiched version was ‘not robust’…. (and showed a clearly erroneous uptick ending in the 1950s)

        Yet it was held up by the media as another ‘hockey stick’.

        Perhaps the authors did not foresee this misrepresentation of their data.

      • markx says:

        And if you don’t like the sources, do your own counts here:
        (on SKS )

        This (below) is simply factual:

        Note he had 7 categories, which were then rolled into 3 categories
        1. Endorsements (including implicit and explicit; categories 1–3
        2. No position (category 4)
        3. Rejections (including implicit and explicit; categories 5–7).

        The top category (1) covers everything from 50% to 100%.
        The other top categories (2 & 3) cover everything from 0% to 100%.
        The bottom categories (5 to 7) cover from 0% to 50%.

      • tony duncan says:


        I read that post of Brandon’s when it came out. That was why I brought up the comments from Lucia that seem to clearly point to an attempt to accurately describe and rate the papers.
        As I said there very likely may be mistakes, and without really understanding all the issues there may be cases that are either negligent or inappropriate assignation, but showing individual cases that amy or may not be wrong, i do not see changing the conclusions by very much. As with Lewandowsky this is not a double blind control tested paper, and there may be some bias, but it would certainly be simple enough to redo the test in the same open way that they have done and then we would see if the consensus is only 92% by some other subjective factor>
        The thing is with THAT study there would surely be cases that could be picked out where ACC supporters could wail and gnash their teeth about how awful and distorted it was.
        I seriously doubt that on balance there would be a very big difference.
        As I siad this study just conforms what is already obvious by anyone who explores the issue. There is easily an order of magnitude MORE agreement about the basic theory of ACC than there is dissent from it. I see no rats fleeing a sinking ship as I have seen predicted for the last 5 years by deniers.

      • markx says:

        Tony, no one is going to abandon a perfectly good (pirate?);-)ship which is still attracting research funds.

        In the end I predict we will reach the point where the numbers on temperature rise and sea level rise will land somewhere in the middle, and both sides of the debate will then declare victory.

        And in the end (I believe) it will be a far slower disaster than was initially predicted (as is indicated by the disappearing C in AGW, and now the demise of AGW and its replacement with ACC).

        We likely yet have ample time to respond.

      • tmac57 says:

        And in the end (I believe) it will be a far slower disaster than was initially predicted

        Well,at least you are finally admitting that it will be a disaster. Making progress

      • markx says:

        Oh, I’m so sorry to give you false hope, tmac.

        Another typo.

        I meant: And in the end (I believe) it will be a far slower ‘disaster’ than was initially predicted (as is indicated by the disappearing C in AGW, and now the demise of AGW and its replacement with ACC).

      • tmac57 says:

        Another typo? Or maybe a ‘fraudian’ slip?

  18. markx says:

    Basic theme is we must trust opinion of the experts.

    But what makes one a climate scientist?

    How well do the authors of these titles below to understanding atmospheric physics?:

    (Titles only. All are Category 2, endorse but not quantify – search term ‘climate’ on SKS )

    1. Biological Diversity And Neptune Realm
    2. Biological Diversity, Ecology, And Global Climate Change
    3. Climate Change Negotiations Polarize
    4. Climatology And Society
    5. Global Warming – Evidence For Asymmetric Diurnal Temperature-change
    6. Model Estimates Of Co2 Emissions From Soil In Response To Global Warming
    7. Photovoltaics And Materials Science – Helping To Meet The Environmental Imperatives Of Clean-air And Climate Change
    8. Potential Impacts Of Global Climate Change On Pacific-northwest Spring Chinook Salmon (oncorhynchus-tshawytscha) – An Exploratory Case-study
    9. Response To Skeptics Of Global Warming
    10. Alternative Energy-resources – A Kenyan Perspective
    11. Carbon Tax As A Dynamic Optimization Problem
    12. Climate Forcing By Anthropogenic Aerosols
    13. Deriving Global Climate Sensitivity From Paleoclimate Reconstructions
    14. Ethical Issues Concerning Potential Global Climate Change On Food-production
    15. Global Climate Change
    16. Global Climate Change – Ecosystems Effects
    17. Interactions Between Hydrodynamics And Pelagic Ecosystems –
    Relevance To Resource Exploitation And Climate Change
    18. The Social And Public-health Implications Of Global Warming And 19. The Onslaught Of Alien Species
    20. The Use Of Iron And Other Trace-element Fertilizers In 23. Mitigating Global Warming
    21. Time-dependent Greenhouse Warming Computations With A Coupled Ocean-atmosphere Model
    22. Agriculture In A Greenhouse World
    23. An Empirical-analysis Of The Strength Of The Phytoplankton-dimethylsulfide-cloud-climate Feedback Cycle
    24. Co2 And Climatic-change – An Overview Of The Science
    25. Global Vegetation Change Predicted By The Modified Budyko Model

    I have listed completely the first 25 titles of the search, and italicized those which may have specific knowledge on the topic … but, the rest?
    Well, I will leave that to individual opinion.

    • tony duncan says:


      another seemingly reasonable point that is a common denier tactic.
      Of course biologists are not experts in climate sensitivity and atmospheric dynamics.
      What is the point of this list?
      it shows in many cases empirical evidence for ACC from outside of the contentious issues of the science psuedo science gobbledygook that gets vomited back and forth on the blogs.

      yes if there is some major new evidence that shows a factor mitigating ACC in ways not understood by current theory a numbers of those papers will be meaningless.
      but a number of them give ancillary support to ACC, which gives some credence to the idea that ACC is pretty accurate. No reason not to include them in a study such as thing

      • markx says:

        Gee Tony, do you think Cook’s ‘97% consensus’ is meaningful or not? When a huge proportion of his “pro” papers are simply a case of citing of the most recent dogma by people who very likely do not know one way or the other.

        And may I point out that you have above used a very common CAGW believer tactic: using the phrase “common denier tactic” to deal with a presentation of facts.

        It is likely you will soon be muttering about “conspiracy”.

        tony duncan says:May 29, 2013 at 12:43 pm
        another seemingly reasonable point that is a common denier tactic.

      • tony duncan says:


        I use “common denier tactic” because I have been trying to have discussions with deniers of ACC for about 5 years on blogs. It is purely a matter of my personal experience, of which I have a LOT.
        In this case you are arguing that a large number of studies do not address the physics of ACC directly. There is nothing about that that disputes the claim of 97%. So I term it a tactic because it is irrelevant to the issue. If you want to remove those studies from the picture for a specific point that is fine, but then we need to discuss the specific point that somehow you think undermines the papers validity.
        If only 3% of papers about ACC support the physics of CO2 and sensitivity consensus, clearly that does not mean that 97% oppose it. Do you have reason to believe that the # of papers that deal with the actual physics and atmospheric and oceanic and other factors are significantly less than 97%. it should be very easy to show that. You could easily take that sup set and make study to determine what the percentage is
        I find it humorous that you use another denier tactic of preemptively protecting yourself from the conspiracy claim. As I said earlier, from personal experience I have seen this and the use of conspiracy theorizing to support attacks on ACC, so judging from your responses on this blog and that you have used other “tactics” of deniers I would not be surprised if you did start suggesting conspiracy theories. However I will not accuse you of such unless you actually engage in it.
        And I only started using those terms because you started using the biased “playbook” regarding SkS. I tend to mirror the tone of the person I am reacting with. If someone is interested in sharing information and points of view I generally have valuable interactions with them, if not I often learn something anyway.

        YOu have not done much searching on the question of the validity of the papers being questioned, especially regarding Tol. I reread the twitter back and forth and it is the typical politicized arguing that I see all the time.
        You fail to point out where Tol’s or Bet’s responses undermine the conclusions of the paper. From reading the exchange the only content in it from Tol says the paper UNDERrepresented the consensus by misclassifying his papers and missing many more that support ACC. What am I missing here?

      • markx says:

        tony duncan says:May 29, 2013 at 4:08 pm

        What am I missing here? (re Tol twitter exchange)


        In this case you are arguing that a large number of studies do not address the physics of ACC directly.

        No, the papers do not need to be individually examined or omitted.

        But what you have there is an inflated consensus of the largely uninformed.

        I do agree with Mosher it is a pointless issue to debate; anyone depending on climate related research funding is hardly going to express a contrary opinion with such a divisive issue.

        Tol’s Twitter comments interested me as his statements agree with my thoughts:

        “A silly idea poorly implemented.”
        “Most importantly, consensus is not an argument.”

      • tony duncan says:


        “But what you have there is an inflated consensus of the largely uninformed.”
        EXACTLY, and that is because there IS a consensus and every researcher knows (s)he does not have to reinvent the wheel.
        I am quite confident that in biology research is effectively ONE HUNDRED percent not considering the possibility that natural selection could be completely wrong. I bet it is more than 99.9% of papers do not address the question of whether evolution is actually happening, and yet NO-ONE has a clue how life actually formed. I would hazard that this is true in a large number of scientific disciplines. Here the BIGGEST question is a complete mystery yet there is a vastly larger consensus of the uniformed than in climate science.
        You make another assertion that “papers do not need to be individually examined or omitted.” without being clear about why my point is not valid that they SHOULD be individually examined and only those that deal with attribution and temp records be considered in order to test you contention that the 97% figure is not valid.

        I could go on here about philosophy of science and ways of determining when a science is on the verge of being untenable, but you would not engage with that. Of course we are not really having a honest dialogue here, as is usually the case with deniers you don’t appear to have any interest in actually discussing issues in a way that leads to an increase in knowledge on both our parts. But as I said I tend to learn things from these kinds of interactions as well.

        and of course you went to denier tactic “climate funding”. As I stated previously I do in fact know some climate scientists, one is actually quite famous, and none of them is making very much money, and none of them has ever been dishonest with me, and none of them is deliberately falsifying or ignoring issues so that they can preserve their funding. I have a clear enough grasp of the science to ask pertinent questions and to weigh responses. I must warn you that you are peeking around the conspiracy corner in pretty much exactly the way that deniers do. You will of course deny that, and make some sort of deflecting statement, or just attack me with an “AHA you ARE accusing me of conspiracy JUST as I predicted you would.”
        You see the difference between a denier and a skeptic is that a skeptic does not get upset when he is wrong, or when presented with information that affects his belief structure, and he acknowledges valid points that someone they are discussing an issue with makes. but a denier HAS to be right and has to “win” an argument, and a denier keeps looking for rationalizations until some crisis is reached that causes a complete overhaul in their belief system. this possibility is quite threatening so they attack anyone that presents them with ideas and information that bring any of their points into question. As such you completely ignore most of what I actually have written, for instance the content of the Tol Dana anti-discussion and the very detailed explanation for why this idea is not silly and is not an “argument” for consensus, but a straightforward presentation of the fact of consensus. Of course this has probably just turned into an anti discussion, as I doubt you will respond well to the content of this comment.
        But rest assured I am happy to have real discussions on specific issues, and am happy to be shown when I am wrong. I am no expert in climate science and i do not hesitate to make assumptions, so I am often wrong in one way or another

      • markx says:

        Tony, I am very sure that very few climate scientists get rich doing this. Scientists are often poorly paid for what they do, and are at the whims of politics and fashions (in research that is!)

        All the more reason to do the research which is expected of you, and to write up in a manner that ensures the next round of funding comes your way.
        And this requires no conspiracy, it is simply the way the system works – policy is set, funds are applied, and the machine continues until there is a major change.

        Re debating the 97% issue one paper at a time. Simply take a quick glance through the list above. Citing the opinions of most of those people is rather meaningless and does not add to the certainty of the science.

        Look, if you think it was a high quality, useful bit of work which has some scientific significance, then I will leave you with that opinion.

        And I’ll stick to my opinion: That it was a fluffed up bit of contrived dross engineered to create headlines.

  19. d brown says:

    “No, it’s a war against bloated government power.” Ok, take one. the end of life as we know it or maybe “bloated government power.”

  20. sailor1031 says:

    From the paper’s abstract:

    “We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming”

    On which planet is a minority of 32.6% “a consensus”? It seems we need to know much more about the 66.4%. Also perhaps we should discard the IPCC political summaries in favour of the IPCC technical reports (they do differ substantially you know).

  21. Canman says:

    Here are a few things I would like to note. From the AGW side, I see a lot of shrillness and demonization of opponents. There are attempts to conflate climate skeptics with creationists. The pejorative term ‘denier’ seems to envelope everyone who does not agree that CO2 is the worlds number one problem and must be stopped right now. I can’t help but be reminded of Jimmy Swaggart saying that all catholics are condemned to go to Hell.

    Another thing is that I’ve come to the conclusion that a large part of climate science is opinion! It’s a guess, an educated guess to be sure, but still a guess. How do you program one of these elaborate climate models when you don’t know what the feedbacks values are? Somewhere, someone is going to have to fudge something. When I see model runs plotted on graphs, observations tend to come in below projections. What is a consensus? It is a pol of guesses. AGW is the only science topic where I see a consensus used as a main argument. With evolution, there is the pol of ‘Steve’s’, but that is a response to creationist pols. Evolution is easily argued with fossils, morphology and now genes.

    Another thing is that this collection of ‘expert’ climate scientists is beginning to sound suspiciously like a priesthood. A scientist may devote his life to some esoteric field and make an important discovery. He (or she) will then publish it in a journal. Is this holy knowledge then the province of other scientists and academics who are the only ones allowed to propound on it, or are others allowed access to it? Could someone outside of the academic walls, say a patent examiner in Zurich be allowed to add to it? Is it possible for an amatuer to understand and critique it?

    • Mal Adapted says:


      If you got your information from scientific sources (journal articles, conference proceedings and the like), rather than from blogs, you’d have a better understanding of the scientific case for AGW, and why there’s a consensus among the scientists doing the work.

      Just sayin’.

  22. tmac57 says:

    AGW is the only science topic where I see a consensus used as a main argument.

    Wrong! The data, both modeled and observed,along with physics are what the main argument is based on.The consensus is just what the majority has concluded after vast amounts of research has been done.

  23. John Bowles says:

    If you believe in CAGW then why are you still driving a car? Using electricity? Heating your house? Come on and show the world that you take it seriously and give up all that high living for the sake of the planet and the children.
    Just sayin’!

  24. markx says:

    Remarkable statements by Tim Yeo (Yes, that’s Mr several hundred thousand pounds per year of green consultancy outside of his government role):

    • tmac57 says:

      I’m not sure why a member of parliament’s opinion should have any more weight than any other non-scientist as to the level of contribution of warming by humans,but the last sentence of that article concluded

      Asked about the comments this afternoon, Mr Yeo said: “It is possible there are natural causes as well, but my view has always been that – for twenty years – I have thought the scientific evidence has been very convincing. The strong probability is that it is man-made causes contributing to greenhouse gas concentrations.”

  25. markx says:

    Steve Mosher sums up a lot here (commenting on )

    Steven Mosher (Comment #113257)
    May 17th, 2013 at 11:15 am

    ‘Remembering AGW stands for anthropogenic global warming, or global warming caused by humans …[...]. ”

    I’ve been saying for quite sometime that fighting over the 97% is rather silly, when the real fight should be over what we mean by

    Cooks trick is this.

    1. In PR material AGW means ‘Humans cause dangerous warming that can only be solved by immediate mitigation’.

    2. In studies of “consensus” AGW means ‘C02 causes warming’.

    …… there is a scientific consensus (that doesn’t matter) on the proposition that C02 causes warming.

    The PR version of AGW isn’t even science.

    • tony duncan says:


      if one looks at this issue completely a historically and only looks at the PR from the ACC side and ignores much of the science there is some relevance to Mosher’s position. Actually I have similar reactions to Mosher and Pilke because they often ignore the history and politics in order to attack ACC scientists. It is a major reason of my distrust of Pilke because he is quite sophisticated in his understanding of both. They both do come up with valid points though.
      But he is presenting a rather unskeptical view.
      There was nothing that I saw about the study that pretended to do anything but show there is a strong consensus that CO2 is a major factor in current warming>
      Unless you do not read any skeptical blogs or don’t read comments on almost any article on the web that comes out about ACC you will see MANY people contending that here is no consensus about ACC. Many people argue that the scientists are lying and falsifying data to make it LOOK like there has been warming, when there really hasn’t been. MANY people saying there is NO consensus and that AMNY scientists don’t believe it is happening or that the warming is almost all due to natural variability. Mueller was savagely attacked for his and Curry’s paper showing the warming. Curry herself attacked the conclusions of one part regarding attribution.
      The paper presents what is glaringly obvious to anyone who looks at the issue for any length of time, that the vast a majority of scientists involved in the issue accept the physics of CO2. The Marcott paper was savagely attacked because the part that THEY disregarded showed rapidly increasing 20th century temps. The “hide the decline” was a HUGE denier argument, that is still in use today. Trenbeth’s “it’s a travesty we can’t find the warming” has been used over and over as proof that the scientists KNOW it’s a scam. Climate-gate was to a large extent about destroying the raw data and hiding it from noble deniers who would prove the deceit. That is STILL being used today. Hansen is constantly being accused of increasing modern temps and decreasing older ones arbitrarily just to fraudulently support ACC.
      Yes, I am sure yo,u Mosher, and many others who question the DEGREE of ACC warming, accept that the modern temp record is not fraudulent and that CO2 definitely plays a role, but there are a hell of a lot of people who don’t and a HELL of a lot more that are confused.
      I would be happy to get on with the question of how much uncertainty is there and what policy is indicated.
      My conjecture is that those who are concerned about the politics, which is most deniers don’t want that to happen, because it limits the arguments against ACC so they will fight this paper as they fight Marcott and anything else that might be “used” by alarmists to implement any action on climate change.
      Mosher is right. people should say, OK, there may be some faults with the paper, but it is basically accurate. What is the range of scientific opinion and what are the potential consequences, and what possible policy prescriptions are suitable for the most reasonable and effective response.

      • markx says:

        “Hide the decline” was really a pretty ordinary bit of work, and in my opinion meant to downplay imprecision and uncertainly and to contribute a neat ‘marketing tool’. Not very uplifting science by any stretch of the imagination.

        “Trenberth’s missing heat” is equally interesting, occurring at a time when the catch-cry was “the science is in”… clearly the physics and models did not match what was being observed, yet still they were sure they were right (and they may be proven correct in the future, but they sure as hell did not know that then.

        Rushing into policy decisions with inadequate information on the likelihood, degree and timing of the threat plays into the power grabbing hands of huge self serving bureaucracies such as the UN and the World Bank, and has all sorts of unintended consequences:

        Such as European countries being paid to shut down antiquated power stations which would have shut down anyway, huge energy multinationals teaming with huge Asian conglomerates to accrue carbon credits , and now US forests being cut down to supply wood pellets to meet Europe’s legislated renewable energy requirements. Not to mention massive energy cost increases and subsequent economic effects.

      • tony duncan says:


        again these are just assertions on your part that assume, in every case, motivations that are part of the denier “playbook”. It is of course possible that you are right, but you are setting up the premise of conspiracy when all I see is scientists dealing with reality.
        Of course the main thing is that you are completely ignoring the point of my comment, that there are huge numbers of people who find all sorts of rationalizations to argue there is no consensus and there is no warming and if there is warming it is not due to CO2.
        “hide the decline, and “missing heat” were and are completely distorted by people over and over and over again.
        And of course the simple explanation for “hide the decline”, is “why put data in tht you know is wrong, especially when you explain it in the text, and when this is a piece of research that you have no reason to think anyone outside of a small group of experts is ever going to see. HOW can this be a marketing ploy if you have no idea when you make it that it will be USED for marketing

        as for missing heat, yes scientists do NOT figure everything out about every theory and have all the data to support it at all times. You find it “interesting” when this happened and that the models did not match observation. I too find it interesting but see nothing unusual or in any way odd that a science has aspects that are not understood or do not fit well with current theory.
        As i commented elsewhere, Evolutionary theory will like ALWAYS have “missing billion years of the origin of life” The Big bang has had the horrible “dark matter” and “dark Energy”, that dwarf “missing heat”.

        And then you change the topic to “rushing into policy decisions” another part of the denier playbook and play the “evil government” card. Of course I don’t deny that policy has to be carefully thought out and consequences weighed. Nor do i doubt that the scientific basis for the policy has to have a certain level understanding in order to make rational decisions. Nor do I doubt that wrong choices can be made that have unintended consequences. Nor do I doubt that wrong choices HAVE been made
        as i said this is not a discussion, which is too bad. I have responded to each of your points so far but you are steering us way off topic, for which I could assume all sorts of nefarious reasons.
        Let’s stick to the paper and you addressing at least some of the points I made in reference to the validity of the paper and the rational and value that the paper has in an extraordinarily polarized issue that has potentially serious consequences.

      • markx says:

        So you think we all should have reacted immediately to the original strident warnings of 6 degrees c and 5 meters of sea level rise by the end of the century (not to mention the more recent ‘projected’ 0.5 C rise which did not occur by the end of the first decade of this century.

        I think a little debate was warranted, and the doubts about the precision of the science was spot on. You may see it differently.

        The Paper. It is all above. Anyone who thinks mankind has contributed anything to warming the climate (oh, that’s now ‘changing the climate’, right?) ends up being counted in such a silly survey. If I wrote a paper and had reason to comment on human influence, my opinion would pu me in there too.

        But do I think it is looking like an emergency, a fast developing disaster? Nope.

        And do yourself a favour and lay off the ‘tactics’ and “playbooks’, there is no such thing, just people with opinions which happen to differ from yours. It does not win arguments, and you cheapen yourself and appear as a pre-programmed mouthpiece. We have heard it all before.

      • tony duncan says:


        unfortunately there are “tactics” and “play books” odd that you deny it now since you were the one who started it. this is a huge ideological/political controversy and as such both sides employ tactics and play books. that is not always bad, certainly SKS is specifically a playbook, but they are at least explicit about it.

        And now you are making assertions that are basically false. I have already corrected you on the 5 meter lie. I have never understood why people post things they know will be shown to be wrong, when they know the person can point to exactly where it was pointed out to them before. All it does is reinforce the idea that you are not interested in real discussion.
        As for the 6° there have ben some people who suggested that, but certainly not the IPCC.
        Of course the “projected 0.5C* rise” is always dependent on many other factors.
        And there has always been plenty of debate about exactly all these issues (except the mythical 5 meter sea level rise) including the non existent precision that you are inventing.
        It is NOT me seeing it differently it is looking at the reality, not a biased interest in painting everything from a denier viewpoint.
        As I said this is a very political issue and I certainly think there are people and groups that have and do exaggerate the problem in order to fit their agenda.I am always skeptical of claims that do NOT rely on the best science at the time. There are a number of issues I have taken exception with by political advocates of ACC. I disapprove of those things partly because it is distorting the science and partly because I think it is a bad strategy to not be completely honest.
        And then you double down and mischaracterize the paper by saying “anyone who think mankind has contributed ANYTHING to warming” when you broke down how the paper rated research. Your statement means that someone who said ACC was only contributing 5% would be part of the 97% consensus? is that accurate?

        then you fall back on the denier “tactic” of “climate change”. You do realize that it was Frank Luntz the republican consultant suggested republicans use the term in order to increase uncertainty for political purposes. the same strategy used by tobacco advocates regarding cancer. And the allegation that ACC advocates changed the name for nefarious reasons has no basis in fact. the reason is because it is more accurate. Global warming is not “wrong” but does not mean that warming happens everywhere all the time and at a constant rate. As is evident by the attacks deniers make using weather, such as cold winters in Europe or other places, when they totally ignore that ACC specifically predicts that there will be changes in air pattern that will absolutely cause colder weather in places. this is NOT something that was invented after the fact, it has always been part of the theory.

        And you are completely misunderstanding me. I have no interest in winning an argument, I am interested an accurate understanding of the issue.
        Pointing out when you are using pre programmed inaccurate assertions does not cheapen me. the reason I point these things out to you is because i HAVE heard all those spurious arguments before. I am only interested in reasonable ideas that are backed up by valid facts.

      • markx says:

        Hansen and 5 metres: Repeated it in his most recent paper. See Fig 7 and comments below. Throws in the odd ‘preposterous’ but keeps explaining how possible it is.

        see more detail here:

        markx says:
        May 30, 2013 at 1:21 pm

      • markx says:

        tony duncan says:May 29, 2013 at 4:42 pm

        Hansen is constantly being accused of increasing modern temps and decreasing older ones arbitrarily just to fraudulently support ACC.

        I’m glad you mentioned this.

        Certainly the GISS records have been and continue to be much adjusted. The value set for 1934 has been changed 5 times over the last 10 years, whereas the value for 1939 has changed 6 times over that period.

        You will be pleased to know that while 1934 was regarded as warmer for a long time, 1998 had more recently temporarily edged ahead, but then recently 1934 regained its leading position.

        However, it appears that very recent changes to 2010 and 1998 have now handed the preeminent position to 2010.(a more skeptical person than I might think that the value of 1998 being warmer than 1934 is now diminished in comparison to the value of it being cooler than 2010 ..)

        But me, I have no idea why these numbers require constant adjustment.

      • markx says:

        edit: correction above:

        “The value set for 1934 has been changed 6 times over the last 10 years, and the value for 1998 has also changed 6 times over that period.”

      • tony duncan says:


        this certainly sounds like conspiracy. I too do not know specifically why the numbers require constant adjustment. Do I believe that all the scientists who do research that rely on these numbers are just ignoring this and turning a blind eye, and are either scared of Hansen or are supporting some sort of fraud where the this data is used to make determinations in an issue that is SO contentious.
        No I do not believe that.
        Are the figures secret and no one is allowed to look at them. Are there NO honest scientists who understand the importance of this and are willing to point out such blatant fraud. I don’t know.
        Am I blindly trusting that there is SOME sort check on this sort of thing, especially since so many people have commented on this. Yes. I could be wrong. I would think that since Hansen is one of the most hated scientists in modern times, that someone would have really done something about this if there was a real problem. Why has not Inhofe started an investigation and forced Hansen to explain all this adjustment. It has been years and i have seen nothing but innuendo and assertions. Why?
        Markx, THAT is being skeptical. I do not assume that it there is corruption and fraud, but I don’t declare it to be impossible. I see a situation where it would be extremely easy to determine fraud because there is a huge group with an enormous degree of motivation and power to prove fraud, yet year after year all I see are allegations and assertions. As soon as someone shows me a real indication of fraud, am totally ready to reassess many other denier assertions that I don’t give much credence to.
        Again you source WUWT. I can counter those with Think Progress all day long. The source you post makes it appear to be an absolute case of fraud. HOW could 1934 lose .5° and 1998 gain so much and much of this happened when Hansen was working for George Bush.
        Again a skeptic would take this information and see what response other scientists have about this issue. On google I see a 6 million hits that mention this huge fraud, Almost ALL of them on right wing or denier sites. Have you looked at ANY response to these accusations. Deniers are not interested in information that goes against their ideology.
        This is an extraordinary claim of fraud, and in this case I disagree with Sagan, it does not require extraordinary evidence. it just requires some ACTUAL evidence. Why has no one provided any? Or unlike me, are you able to find some?

      • markx says:

        Not fraud or a conspiracy … simply clumsy incompetence, turbopowered by ‘Noble Cause delusions of Importance’. (IMHO)

        I rarely link to WUWT (as it upsets tmac and then he upsets me in turn by linking to SkS) but that happened to be a nice simple summary of some of the more minor record changes which have occurred.

      • markx says:

        These records apparently all require frequent revising:

        Here is HadCRUT(from Wiki … yeah, I know..)


        HadCRUT4 was introduced in March 2012. [2]It “includes the addition of newly digitised measurement data, both over land and sea, new sea-surface temperature bias adjustments and a more comprehensive error model for describing uncertainties in sea-surface temperature measurements”. [3] Overall, the net effect of HadCRUT4 versus HadCRUT3 is an increase in the average temperature anomaly, especially around 1950 and 1855, and less significantly around 1925 and 2005. [4]Also, the warmest year on record, which was 1998 with HadCRUT3, is now 2010 with HadCRUT4. [5]

        HadCRUT3 is the third major revision of this dataset, combining the CRUTEM3 land surface air temperature dataset with the HadSST2 sea surface temperature dataset. First published in 2006, this initially spanned the period 1850–2005, but has since been regularly updated to 2012. Its spatial grid boxes are 5° of latitude and longitude. A more complete statistical model of uncertainty was introduced with this revision, including estimates of measurements errors, biases due to changing exposure and urbanisation, and uncertainty due to incomplete coverage of the globe by observations of temperature.[6]

        HadCRUT2 was the second major version of this dataset, combining the CRUTEM2 land surface air temperature dataset with the HadSST sea surface temperature dataset. First published in 2003, this initially spanned the period 1856–2001, but was subsequently updated to end in 2005. Its spatial grid boxes are 5° of latitude and longitude. An estimate of uncertainty due to incomplete coverage of the globe by observations of temperature was included, as was a version with the variance adjusted to remove artificial changes arising from changing numbers of observations.[7]


        HadCRUT1 was the first version of this dataset. Although not initially referred to as HadCRUT1, this name was introduced later to distinguish it from subsequent versions. First published in 1994, this initially spanned the period 1881–1993, but was subsequently extended to span 1856–2002. HadCRUT1 at first combined two sea surface temperature datasets (MOHSST for 1881–1981 and GISST for 1981–1993) with an earlier land surface air temperature dataset from the Climatic Research Unit. The land surface air temperature dataset was replaced in 1995 with the newly published CRUTEM1 dataset. Its spatial grid boxes are 5° of latitude and longitude.[8]

      • tony duncan says:


        So you think changing the 1934 temp by .5C° is a minor record change? and that it was accomplished by clumsy incompetence? that was certainly not the implication of the WUWT post.
        I still want to see evidence of that.
        Again this is a denier tactic. make an assertion and have no facts to back it up and attribute motivation that supports a narrative of some sort of corruption.
        Then you post HadCRUT and it appears to be quite competent and reasonable. What is the difference between the methodology of GISS and HadCRUT that indicates incompetence or hubris?

        These types of things are standard propaganda techniques. make an assertion, imply some motivation, and then when challenged to support it step back make other assertions and let the doubt hang in the air.

        As I previously said, I know some climate scientists and have had discussions with them, and my interactions with them completely undermine the way they are presented by the deniers.

      • markx says:

        GISSTemp is code, that is why it changes(?) … some exploration here with Chiefio;

      • tony duncan says:


        I am getting whiplash. Is it fraud or not fraud? This post clearly says fraud AND conspiracy between ALL the sources of global temps. He was very convincing.
        but then a SKEPTIC doesn’t just accept assertions from one side.
        I ask again, what is the response of scientists and people who aren’t deniers to these allegations. Are the deniers so incompetent that they cannot get actual evidence of this obvious world shattering conspiracy to all the honest scientists who would then condemn and overturn this horrible travesty that passes for science.
        I have seen these accusations over and over again about almost every single aspect of ACC. Every one that I have had enough knowledge to competently explore has turned out to be FOS. Many, such as this I don’t understand the specifics, but I wait and wait for the house of cards to fall, as it is predicted to all the time.
        Of course being a skeptic I don’t just discount the accusations, but I am always kept waiting and waiting.

      • tmac57 says:

        Hmmmm…looks like Chiefio posted a very credulous review of Rossi’s so called E-Cat device (cold fusion). Not really a good indicator of a person who is a good judge of science in my opinion.

      • markx says:

        Tony – I for one do not know if it is fraud or not. More likely it is noble cause corruption in my opinion… the belief in ‘the truth’ is so strong that adjustments and modeling are believed and published if they show expected results.

        Having a data set which constantly changes each time and extraction program is run must rate as some sort of incompetency. Lack of easy access to the original base data looks like deliberate obfuscation.

        But early century temperature peaks do show that current temperatures are not unusual. (That does not necessarily prove or disprove anyone’s theories).

        When the we see the terms “unprecedented’ and ‘records broken’ relating to a weather event we have just seen a blatant contradiction.

        The great degree of accuracy of past measurement implied by declaration of a 0.7 C rise of global temperature over 140 years is a stretch of credibility.