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Climate Hustle

Understanding climate denial

Posted on 28 September 2011 by John Cook

There are a number of areas of science where the evidence has become so overwhelming that a scientific consensus forms. For example, the consensus on the link between smoking and cancer, that HIV causes AIDS or that humans are causing global warming. Where there is a scientific consensus, there are often movements that deny the scientific evidence. All of these denialist movements have been found to share 5 common characteristics, including cherry pickingconspiracy theories and fake experts.

Understanding the denial of scientific evidence is a crucial element to putting the climate controversy into proper context. The first step is recognizing that the process of denial is to be distinguished from cases where the title 'denier' is used derogatorily. Complaining about the word 'denier' can be a form of denial itself, using concern trolling to avoid a serious discussion of the scientific evidence.

Certain defence mechanisms are tell-tale signs of denial. In one experiment, people were asked if they believed there was a link between Saddam Hussein and the terrorist attacks on 9/11. Those who answered yes were shown evidence that there was no such link, including a direct quote from President Bush. Despite the overwhelming evidence, only 2% of participants consciously changed their mind (although interestingly, 14% denied they ever believed in the link despite indicating so in the initial survey).

The most common response was attitude bolstering. This involves bringing to mind arguments that support pre-existing views while denying any counter evidence. The process is reflexive and almost sub-conscious. Attitude bolstering has an unexpected and unfortunate consequence. When one encounters threatening evidence, the cognitive process of bringing supporting arguments to the fore results in a strengthening of one's views. This is known as the backfire effect, where debunking a myth can paradoxically end up reinforcing the myth. The effect is strongest among those whose views are already quite strong.

Is it any wonder that so few who deny scientific evidence change their mind? But don't forget that 2%. The rare person who was "skeptical" about climate change but then considered the full body of evidence is the exception that proves the rule. In Confessions of a Climate Change Convert, D.R. Tucker perused all the scientific evidence, became convinced that humans are causing global warming and uttered the famous pronouncement, "I was defeated by facts".

Craig Good from Skeptoid, describes how he came to be convinced of the evidence in I, Global Warming Skeptic:

Since [Peter Gleick's] talk I have spent a lot of time on a site he recommended, There they have taken each of the most common science questions, numbered them, and carefully addressed them with the current science. The answers are even presented in basic, intermediate, and advanced formats so that there’s likely to be one matching the reader’s level of scientific knowledge.

With the caveat that a few of the questions don’t belong on their list (42, 63, 105 and 165, at least) because they are economic and/or political rather than scientific, I highly recommend the site.

So, yes, I am now persuaded that anthropogenic global warming is real. That’s because I’m a skeptic.

I recently received an email from a blogger Nathan McKaskle who informed me:

"You changed my mind about global warming. Up until today I was a big time skeptic for a number of reasons. Great site with a wealth of information that addressed most of my concerns."

Unfortunately Nathan closed his blog down (otherwise I would've linked to his blog post on this subject). Ironically, he closed down his site due to discouragement, not knowing whether he'd changed a single mind through his blogging. It's a sentiment many of us bloggers can relate to, I'm sure.

These examples of minds being changed by the evidence reaffirms Skeptical Science's key mission of presenting the many lines of evidence for man-made global warming. Another key to putting the climate controversy into proper context is understanding the phenomenon of denial. Skeptical Science will continue to examine the 5 characteristics of science denial and how they manifest in many climate myths. It is by understanding how some deny the evidence that we are able to point to the scientific evidence.

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Comments 1 to 50 out of 261:

  1. Whilst never being a denier, I did have some lingering doubts about AGW. Reading this site has certainly been an eye openner for me. SkS's insistance on citing peer reviewed science, and the helpful explanations of the regular contributors has shown me the direction in which the evidence overwhelmingly points.
    Oddly enough, a follow-on effect is that I'm more inclined to examine my decisions and attitudes on other topics more deliberately and critically as a result.
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  2. Stevo,

    "Oddly enough, a follow-on effect is that I'm more inclined to examine my decisions and attitudes on other topics more deliberately and critically as a result. "

    That's exactly what I'm experiencing as well. After about 5-years of following climatechange discussion I find myself factchecking and doing source-lookups on a whole range of subjects before accepting the opinion of some (anonymous) internet person (or from friends/relatives). The AGW discussion experience makes me very skeptical on every subject.

    I notice being so skeptical is a pain when 'discussing things' with friends/family and has a tendency to stop an interesting discussion dead in it's tracks.

    There's a lot of bulls**t and non-informed opinion going round as 'fact'.
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  3. John,

    "Ironically, he closed down his site due to discouragement, not knowing whether he'd changed a single mind through his blogging. It's a sentiment many of us bloggers can relate to, I'm sure."

    While few 'skeptics' can be convinced by the evidence I think there is a much larger group that is ill-informed and either: has no real opinion on AGW, thinks it's mostly theory an not manifesting yet, thinks it will not harm them, etc.

    I usually invite this large group to visit SkepticalScience (and other sites) to educate themselves on the topic. This is the group that hasn't dug in yet and likely can be persuaded by solid arguments and evidence, this is the group that every blogger should have in mind.

    In short: SkepticalScience and other bloggers on the science side are simply doing an invaluable job. The sentiment of being unable to change peoples minds is misplaced I think.
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  4. Great and timely article!

    I'm battling my own troll now over on a youtube clip on artic ice who is so full of contradictions I don't know where to start. It feels like hitting a brick wall. You tube "climate skeptics" are the worst of all. They just keep popping up everywhere.

    Should I continue feeding him or just live by the old DNFTT maxim?
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  5. John,

    Don't you find the phrase "climate change denier" a tad ridiculous? I challenge you to find anyone older than primary school who denies that climate changes (natural or otherwise).

    Wouldn't "man-made global warming denier" be a more accurate phrase? Except that's not entirely accurate either in all cases. What do you call a person who agrees with man-made global warming principles but disagrees with one component of it? For example, wouldn't it be more accurate to call Dr Spencer a "high climate sensitivity denier"? Or astronomers, shouldn't they be "increasing atmospheric IR deniers"? For geologists it is probably prudent to call them "fast short-term global warming deniers" (since they believe the climate changes catastrophically over long periods).

    The problem is, there is no clear-cut "do you believe or not". There are many 'shades of grey' (even within the peer-reviewed science those 'shades of grey' shine through). You even see those 'shades of grey' in comments and articles on this site.

    IMO, instead of trying to define "them" (deniers, sceptics, whatevers) isn't it more important to define who you are first?
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    Response: [John Cook] The point of my article is that this is not about labels, it's about understanding the process of denial. The process of denial is bringing to the fore supporting, comfortable arguments while suppressing or denying counter evidence. Examples of this process are cherry picking, or changing the subject, when presented with uncomfortable evidence. Conversely, genuine skepticism is about considering the full body of evidence.
  6. @yocta: I'd give up on Youtube. Every good soldier knows that wherever possible you need to choose the battlefield where you'll confront the enemy.

    Regarding the word 'denier'. As this is a red rag to a bull, I avoid it; preferring instead to use the phrases like 'those in denial'. There always a way to rephrase your response to avoid using the 'd' word.

    The other point to make is that when addressing a particular individual in a comment thread, it's not that person you're trying to influence -- most of the vociferous are usually beyond hope -- it's the 'don't knows' and genuine sceptics looking on that are important. How you conduct the 'argument' -- remaining calm, considered and consistent -- is critical to being influential. You're the one that has to come across as the voice of reason. You must attempt to make your opponent in denial to come across as being unreasonable. So never become too involved in him (isn't he's almost always male?) and instead imagine the undecided onlooker standing over your shoulder as you write.

    Last: never lose your cool. He who stays in control of his emotions, wins.
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  7. @Dale. If people follow my advice regarding 'those in denial', the issue you raise does not arise.
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  8. @5 (response)
    Thanks for the reply John. I will read the articles with that in mind.
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  9. John Russell #6, merely facts (which are taboo) are red rags. I decided to employ 'denier' or e.g. 'liar' where facts are denied or people lie. This in realms like WUWT where arguments play no role. Keeping your cool means getting the bulls in a rage pronto, gets them to show their worthless cards. And this, sir, is setting the battle on enemy ground.
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  10. Dale #5, what the deniers deny is essentially the fact that CO2 is a greenhouse gas. There is no more to it.
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    Response: [John Cook] SkS has been building a database of climate myths for years now and the argument that CO2 is not a greenhouse gas is not one of the more popular arguments. Most of the prominent climate "skeptics" readily concede CO2 is a greenhouse gas.
  11. "Most of the prominent climate "skeptics" readily concede CO2 is a greenhouse gas."

    No, they don't. Because that is logically what you do if you deny the 'A' in AGW.
    If deniers concede the existence of global warming but deny increasing concentration of CO2 is the culprit, then they deny CO2 is a GHG. It is really as simple as that.
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  12. @cRR Kampen. Methinks you over-simplify.

    Only the most uninformed of those in denial deny that CO2 is a greenhouse gas. The more advanced accept that CO2 is a GHG. Some even accept that humans are adding to GHGs. For most of them, where the denial comes in is in accepting that it can result in catastrophic climate change.

    The most dangerous of those in denial are perhaps those that think we'll be able to adapt. The few scientists that are considered to be in denial probably fall into this last camp.

    The biggest problem we have is that those in denial are so lacking in scepticism that they don't disagree with one another, even when they use favourite denial memes that contradict.
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  13. "For most of them, where the denial comes in is in accepting that it can result in catastrophic climate change."

    Well, 'catastrophic' is one word I used to not use, though in view of some special incidents like the tornado season, the Pakistani floods, and processes like ice melting everywhere faster than models would've had it, I reconsider.

    Anyway, your remark - denying that increasing concentrations of CO2 cause climate change - effectively comes down to denying that CO2 is a GHG. I am not oversimplifying at all. I am pointing out the logical fallacy of denialists - which, as you see, is a very simple thing to do.

    If denialists point to some other factor causing global warming, they deny CO2 is a GHG. If in this stage they don't, they are left with the burden of finding some cooling effect that entirely obliterates the effect of increasing CO2 as well. Regress indefinitely...
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  14. CRR Kampen
    AGW deniers don't need to deny the greenhouse effect or that CO2 is a greenhouse gas, claiming that the effect on earth's climate is negligible or small will suffice. This is what prominent skeptic scientists like Spencer, Lindzen, etc., say.
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  15. To illustrate Riccardo's point, Spencer says this:
    So, until someone comes along with another quantitative model that uses different physics to get as good a simulation of the vertical temperature profile of the atmosphere, I consider objections to the existence of the ‘greenhouse effect’ to be little more than hand waving.
    Lindzen says this:
    For reference purposes, the radiative forcing associated with a doubling of CO2 is about 3.5 watts per square meter.
    Monckton says this:
    From the anthropogenic-era forcings summarized in Table 1, we obtain the first of the three factors – ΔF2x≈ 3.405 W m–2
    All of them agree on the change in forcing due to a doubling of CO2 to within 10% of the IPCC value.
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  16. This might be a bit off-topic for this thread, but Eugenie Scott, director of the US' NCSE has a talk up on YouTube describing similar characteristics between denialism in evolution and AGW that she did in Glasgow.
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  17. Riccardo #14, "claiming that the effect on earth's climate is negligible or small will suffice."

    Contradiction in terms, like water is wet but moist nor damp. The very phrase 'GHG' implies a non-negligible effect.

    "All of them [climate populists, cRR] agree on the change in forcing due to a doubling of CO2 to within 10% of the IPCC value." said Kevin C. This means CO2 is virtually no GHG, its effect is estimated to be negligible. Proves my point for at least 90%. Refer to my last paragraph in #13 for the rest.
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  18. Perhaps instead of calling them "deniers" they'd be happier if we called them "revisionists" -- that's what they are trying to do, to revise the science to make it say what they'd like it to say.
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  19. cRR,

    Just because a person in denial says, "the sun caused modern warming" does not exclude a belief that CO2 is a GHG. Similarly, for a person in denial to focus on clouds being a negative (ie: they reflect more than they keep in) does not exclude a belief that CO2 is a GHG.

    Basically, you're completely wrong to state that if they don't think CO2 caused the increased warming that they don't believe CO2 is a GHG. Lindzen for example states in his papers that other factors are primarily responsible for 20thC warming, AND that CO2 was responsible for a very small amount. So at least HE believes CO2 is a GHG, just a very minor one.
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  20. >>>The very phrase 'GHG' implies a non-negligible effect.

    No, it does not. A GHG is one that reacts vibrationally with IR, there is no requirement for how negligible or not the effect is nor any sort of implication there must be. A whole slew of greenhouse gases have been discovered and quantified:

    You are adding an unjustified qualifier.

    While there indeed is a large portion of people that deny that CO2 is a greenhouse effect (or, like to cling to "studies" demonstrating the effect doesn't even exist), that is not the only form of denial.
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  21. *ozone is a greenhouse gas, but it reacts with UV instead of IR. So, scratch my previous statement.

    Back on topic, I think that when it comes to "denier" v. "??", we ought to not let people put words in our mouth. That has two aspects:

    - Don't let them falsely equate a sometimes-used connotation with a word that otherwise perfectly describes the behavior of who is being labeled as such (e.g. "holocaust" onto "denier");
    - Don't let them force an unjustified name for themselves onto us (e.g. "skeptics").

    If "skeptics" want to be known as real skeptics then they ought to do exactly what a real skeptics does, which is look at the entire body of evidence. Otherwise they are (as Tamino has been putting to good use) "fake skeptics," or "deniers" as so often the shoe fits.

    Back even more on topic,

    Since it is actually *not* the case that SkS and the overwhelming majority of pro-AGW blogs and scientists ever use "denier" to equate to holocaust denial, the campaign against "denier" is misplaced. Dragging in people who have not ever implied such a connotation and demanding that they follow a guideline based on a false moral equivalency is (as was said) stark concern trolling and diversionary. The real issue is the science, and what actions would be prudent on our part to take in light of the science.
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  22. #19 Dale, "Just because a person in denial says, "the sun caused modern warming" does not exclude a belief that CO2 is a GHG."

    Yes, it does. If you say the sun caused global warming, then you say the increasing concentration of a certain gas did not cause global warming, thus either denying that gas is a GHG or omitting reference to a cooling effect that must exist somewhere to offset the increase of that GHG. There simply is no cake here that can be both had and eaten.

    "So at least HE believes CO2 is a GHG, just a very minor one." Proves my argument in major fashion.

    #18, I sometimes use that word too. Revisionist. Those deniers that associate the verb 'to deny' with Shoa denial begged for it, happy to oblige.

    All, as matter of fact CO2 is major greenhouse gas. Belief or no belief. Also, global warming is not some kind of mystery! It has a cause even if deniers try to put us up with some kind of magical process.
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  23. The tide is caused by the gravitational pull of the moon than the sun has no gravitational effect on the earth. Sorry cRR Kampen but your logic is faulty, you seem to know just "yes" or "no" and are unable to quantify an effect.
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  24. cRR Kampen Most of those in denial of AGW fully accept that CO2 is a GHG, but assert that negative feedback means that the effects of the CO2 will be inconsequential (e.g. Spencer). Thus they are in no way in denial that CO2 is a GHG, nor do they dispute the direct effect of the radiative forcing from CO2, they just deny that this will cause temperatures to rise. The reason for this is that the fact that CO2 is a GHG and its direct effect on climate are now so strongly established as to be undeniable, even by those in denial (so they have to find ways in which the climate is self-stabilising to minimise the actual warming that occurs as a result of the enhanced greenhouse effect - e.g. clouds).
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  25. Political and religious ideologies compel the vast majority of people who rail against climate science and climate scientists on comments threads to do so. It is virtually impossible to reason with an ideologue.
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  26. On a macro-level, the "climate denial process" has been orchestrated by what I affectionately call the "Climate Denial Spin Machine." This real-world version of the Borg was created and financed by the likes of the Big Oil, Big Coal, and political ideologues such as the Koch brothers, Ruppert Murdoch, etc. Many of the people who post diatribes against climate science and climate scientists on comments threads are nothing more than drones of this sophisticated and well-funded propaganda machine. They have essentially been assimilated.
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  27. @John Cook:

    You state, "Certain defence mechanisms are tell-tale signs of denial."

    Isn't denial itself one the basic defense mechanisms of the human race?
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  28. John Hartz, ideologues cannot understand how someone with integrity could disagree with them. As a result they believe their opponents to be lacking in integrity and dismiss anything uncomfortable that they say. As well there is an element of supporting sides in politics rather than looking at issues. Denialists cannot bear the thought that political opponents might be right on something. I have too many friends that are denialists and it is exasperating. I've seen what's behind the denialism in their off the cuff remarks.
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  29. Riccardo #23,
    ""So at least HE believes CO2 is a GHG, just a very minor one." Proves my argument in major fashion." - said I in #22. Quantification provided. But to paraphrase exactly: the moon and sun exert a gravitational force on the seas BUT the tides are, of course, caused by anything EXCEPT the moon and sun. That is your typical denialist argument.

    #24 Dikran Marsupial: "so they have to find ways in which the climate is self-stabilising to minimise the actual warming that occurs as a result of the enhanced greenhouse effect - e.g. clouds" - Correct. To be precise: global warming occurs and according to denialists its cause is anything BUT the increase of a certain GHG. That means denialists will either have to vastly understate the GHG-characteristic of CO2 (that is: effectively deny that CO2 is a GHG!) AND provide a different explanation of GW.

    OR they will concede to CO2 as a greenhouse gas THEREFORE they will have to provide some major cooling effect that is not a feedback from CO2-increase and leaves a total warming of close to 1 K since 1901 (which, by the way, is just about the increase you would expect from 35% more CO2 in the air). Interestingly this would put them in the camp of AGW realists...
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  30. John Hartz, the spin machine is less important in my opinion than biases of individual polarized persons. I don't think we have top down manipultions by the likes of the Koch Brothers so much as a bottom up movement of people seeking to believe what is comfortable for them to believe. The people that you think of as manipulators are I think themselves captive of this movement. They are in an echo chamber that they have sought out, just like the rank and file denialists. I think they are reinforcers rather than originators of denialism.
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  31. cRR Kampen - Denial has several forms, all of which are problematic when something needs to be dealt with. I feel it's important to be clear on these distinctions, as not all denial has the same pattern.

    * Simple denial - Deny an unpleasant fact entirely. I think this is often seen by those claiming the temperature records are incorrect, that the greenhouse effect violates thermodynamics, CO2 isn't a greenhouse gas, the whole collection of "It's not happening" statements. While almost impossible to discuss matters with, I don't believe this group represents the majority of the skeptics.

    * Minimization - Admit the fact, but rationalize that it's not serious. People clinging to any shred of evidence whatsoever to claim that Climate sensitivity is low fall into this category, and it seems to include a number of those skeptics with some scientific credentials.

    * Projection - It's happening, it's serious, but it's not us! It's a natural cycle, it's the sun, or it's cosmic rays! I'm always surprised more of these folks aren't claiming that it's leprechauns.

    Motivations are a rather separate topic - but one of the big motivators for the rather intense funding of climate denial is economic interests who don't want to see their market dry up. And that pulls in a great many folks who feel a deep need for denial - a basic human defense mechanism. To quote from the Big Chill, rationalization is more important than sex.
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  32. cRR Kampen Sorry, you are not paying sufficient attention to the argument being presented. Denialists agree with the mainstream on the direct GHG effect of CO2, so they do not "vastly understate the GHG-characteristic of CO2". It is also not correct that they have to find a major cooling that is not due to feedback from a CO2 increase. IIRC Spencer claims that cloud feedback will limit the CO2 induced warming.
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  33. Will the Climate Denial Spin Machine come to Lomborg’s resuce?

    Bjorn Lomborg, author of “The Skeptical Environmentalist” and bête noire of climate change activists around the world, has been told that the incoming Danish government will cut off his £1m a year funding.

    Source: “World's leading climate sceptic sees his funding melt away fast,” The Independent (UK), Sep 28, 2011

    To access the entire article, click here.
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  34. #32, but, Dikran Marsupial, the CO2 induced warming is not limited. Its magnitude conforms perfectly to AGW-theory. If denialists want feedback while fully acknowledging the effect of CO2, they will have to show that increase of CO2 is in fact much larger than conventional AGW-theory implies...

    And again, if they think GW is caused by something other than CO2-increase they effectively think CO2 is no or negligibly a GHG OR that there exists, separately, a cooling effect leading to the grand total of +1 K since 1900 (so: 'other warming effect' + CO2-increase + 'cooling effect' = 1 K + 1 K - 1 K = 1).
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  35. Would like to correct a statement in #34 - "they will have to show that increase of CO2 is in fact much larger than conventional AGW-theory implies... " should read

    ... they will have to show that temperature increase by increasing CO2 is in fact much larger than conventional AGW-theory implies...
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  36. KR, your example of 'minimization' effectively comes down to an example of 'projection'. If climate sensitivity for CO2 increase be low, then GW must be caused by, well, leprechauns.

    Right, a bit more on topic. Many denialists believe humanity cannot possibly be so powerful as to achieve feats normally ascribed to Mother Nature. I often ask whether they believe humanity can pollute the oceans. This question seems to be too simple to merit answers and well, I never get an answer. Pity as I always like to explain how an air density equal to seawater would reduce the entire atmosphere to a pool just 10 metres deep - as opposed to the oceans which would cover the earth by like 3300 metres...
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  37. Personally, I use the terms 'denier' and 'denial' in their scientific and legal senses. A person is in (psychological) denial if they hold on to a belief despite having their attention drawn to a preponderance of cogent ( i.e. credible and relevant ) evidence.
    Since a denier does not or cannot accept scientific evidence if it runs counter to their belief system, it follows that they cannot or will not accept any cogent evidence that 'denier' is in any way a scientific term.
    One way a denier will deny being in denial is to assert that the term applies to Holocaust deniers. Yes, it does - but not exclusively. And a Holocaust denier by the way may be a person who is completely unable to accept the cogency of the evidence which proves that some humans can be exceedingly evil. Not every Holocaust denier is an ideologue.

    When I was a small child the Astronomer Royal said that space flight was bunk. That was in spite of all of the then recent advances in rocket science. He was a denier of the evidence from the science of ballistics. Shortly afterwards, the USSR launched Sputnik 1.

    In 1768 a meteor fell at Luce in France. A commission from the French Academy of Science took the testimony of many eye witnesses. That evidence was tampered with and the commission concluded that the stone had been struck by lightning. In 1790 a shower of meteorites fell in France. Despite the physical evidence and about 300 eye-witness accounts sent to scientific journals and organisations, the establishment conclusion was that stones do not fall.

    The most extreme form of denial is demonstrated when a person is so incapable of accepting a fact that they fabricate evidence in support of whatever idea makes them feel comfortable. For example: it is widely reported in medicine that a stroke victim may deny that an affected limb is their own limb. It seems to me to be key to denial that people will most deny facts if those facts carry implications that they are not in control of their own lives and destinies, or implications that some people have no regard for human life.

    Speaking entirely hypothetically: if there is cogent evidence that bogus findings about a social harm are being produced for money on behalf of powerful but asocial people, then it is a virtual certainty that many people will take that evidence as a personal attack on the integrity of the producers of the bogus reports and will reinforce their denial thereby.
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  38. I think cRR Kampen has a point.

    Perhaps a better way of stating the position of denial with respect to greenhouse gases would be to say that these people reject the evidence that:

    "the dominant contribution to the raised temperature of the Earth above its blackbody temperature arises from greenhouse gasses".

    If one considers Dr. Lindzen's position on this, we've just seen that he agrees that CO2 is a greenhouse gas and is in agreement with the value of its primary radiative forcing.

    His rejection of the evidence that positive feedbacks amplify the primary effect of CO2 to the degree accepted by the broader scientific community is based on ad hoc objections that don't stand up to scrutiny. Thus:

    1. His initial assertion for low sensitivity was that the tropospheric warming resulting from enhanced [CO2] would cause the upper troposphere to dry, thus producing a negative water vapour feedback. We know absolutely that this assertion is incorrect. Dr. Lindzen doesn't adjust his views on feedbacks/sensitivity in the fce of this evidence but moves on to a second ad hoc assertion, viz:

    2. The Earth has an "adaptive iris" that opposes temperature excursions from some mean, and which acts via a cloud response that provided a negative feedback. Empirical analysis provides no support for this notion, and in fact recent empricial data (Dessler/Clement) indicates that the cloud feedback is likely to be a marginally positive one (rather than strongly negative). Dr. Lindzen doesn't adjust his views of sensitivity/feedbacks in the face of this evidence, but moves onto a third ad hoc assertion, viz

    3. An analysis of short term TOA radiative response to changes in surface temperature over the tropics as measured by ERBE data indicates a rapidly-acting negative feedback. Independent analysis indicates that this interpretation is entirely an artefact resulting from neglecting heat exchange with higher latitudes and an astonishing "cherry pick" of selected analysis time periods.

    The essential element here is the pursuit of a preconceived view completely in the face of rather well-established contrary evidence. Now we may say that this doesn't mean that Dr. Lindzen "denies" that [CO2] is a greenhouse gas. However he certainly seems to be pursuing a denial that [CO2] acts as a greenhous gas in the manner that is supported by a large amount of independent evidence and analyses.
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  39. cRR Kampen wrote "the CO2 induced warming is not limited. Its magnitude conforms perfectly to AGW-theory.". It is an overstatement to categorically state that CO2 induced warming is not limited by negative feedback, only that the balance of the available evidence is strongly against it. Secondly the observations do not conform perfectly to AGW theory, again that is an overstatement. The observations are consistent with AGW-theory, however the uncertainties in the measurements and in the spread of th model runs, mean that AGW theory doesn't make tighly constraining predictions that exclude other possibilities.

    "And again, if they think GW is caused by something other than CO2-increase" as I said, you are not paying sufficient attention to the argument. Many leading skeptical scientists do not say that the warming is caused by something other than AGW, just that negative feedback means that it [the warming due to AGW] is not a significant problem.
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  40. John @33,

    An interesting article. They quote Lomberg:
    "He was, he says, never a climate-change denier."

    Later they quote Lomberg opining that:
    "Climate change will not cause massive disruptions or huge death tolls. Actually, for the world in general, the direct impact of climate change in 2050 will mean fewer dead, and not by a small amount."

    It sounds like Lomberg is in denial about being in denial about the consequences of increasing CO2 to its highest level in 35 million years in 2100 (Kiehl 2011) if we continue with business-as usual.

    Another quote:
    "The reason he received funding in the first place was ideological," said Ms Auken, environment spokesman for SF, the junior partner in the incoming coalition. "We believe that it is wrong to give funding to specific ideological researchers."

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  41. The following is the type of story that will get the average person's attention and neutralize the pseudo-science poppycok being generated the Climate Spin Machine.

    “The majestic Rockies are delivering a message these days.

    “Climate change is not a theory, not a debate, in these mountains. It is there for your eyes to witness. The glaciers are shrinking rapidly and changing appearance, even from when I first hiked there as a 10-year-old.”

    Source: “Icing the case for global warming: The Canadian Rockies' disappearing glaciers,”, Sep 27, 2011

    To access the entire article, click here.
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  42. cRR - you're missing a key point. The more sophisticated "skeptics" don't deny the greenhouse effect - as Kevin C noted @15, they generally agree on the radiative forcing from increased CO2. That's agreement that CO2 is a greenhouse gas and causes an energy imbalance.

    Where they disagree is on how sensitive the climate is to those CO2 emissions and that energy imbalance. They think it won't result in a large temperature change. But they don't deny that CO2 is a GHG.

    But back to the post, the key point is that those in denial are denying the full body of scientific evidence. They'll consider some evidence, but reject other evidence that doesn't conform to what they want to believe. The "attitude bolstering" point in John's post is an interesting concept I hadn't heard of before.
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  43. Good discussion,

    Chris @38, you make some excellent points.

    I would argue that "skeptics" like Lindzen and Spencer and Christy are in fact denial about the theory of anthropogenic global warming (AGW). It is not enough to accept that CO2 and CH4 are greenhouse gases (GHGs) and that doubling CO2 will increase the global temperature by about 1.1 K. The theory also states that positive feedbacks (water vapour, albedo etc.) will amplify the warming from GHGs alone. There is abundant evidence from paleoclimate data that support that, not to mention solid physics such as the Clausius-Clapeyron equation.

    What is obvious is that these skeptics do not openly deny the theory of AGW (they have to maintain some credibility to manufacture debate), instead they create the perception that they do, and instead on focus on trying to obfuscate, undermine and downplay the situation. Now maybe this is not conscious on their part, perhaps like Lomborg, they are in denial about being in denial.

    Note that Spencer and Lindzen are very cagey and wary of paleoclimate data. There is a reason for this, because those data undermine their entire case/argument for strong negative feedbacks, and for very low climate sensitivity for a radiative forcing of 3.7 W m-2 (in this case from doubling CO2). Note that by ignoring those paleo data they are also denying the full body of evidence.

    Now this is just a simple case, there are many variants on this by which people rationalize that there is not a problem-- they argue that the surface temperature record is unreliable (sadly even when their own data refute that claim, it does not change their minds), they cherry-pick particular datasets and/or short time windows that support their belief that the planet is not warming or accumulating energy, they argue that the warming is mostly due to internal natural variability (ENSO, PDO), or they argue that it is due to external natural variability (the sun), they may even argue that what we are going to experience is of no concern because climate has always changed in the past, sometimes dramatically and one and one and on it goes ad infinitum.
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  44. The real issue isn't one of names or tags; it is one of what a person is willing to accept. In the case of climate change, there is an unreal amount of outcomes that can occur, so vast that individuals have no real way to comprehend how our big experiment will change the Earth, society, and people's lives, from rich to the poor, north to the south, etc. There is the magnitude of warming that has a range, there is a range of effects on the hydro-logical cycle, range of effects on jet streams, uncertainty in extreme weather, drought, etc, etc.

    It is the inability of certain groups of people to accept that range, and that reject that these changes will have strong negative effects on people, society, the environment, etc that is the real problem. A reasonable skeptic will always see the full range of the possibilities, using science a guide.

    I am perfectly willing to accept that climate change may not be a big deal, that it may not result in catastrophe that calls for large changes to the way in which we produce our energy and use land and transport goods, but what I'm not willing to do is ignore the risk that it will. So until people begin to get on the same page on what the range of risks are, discussing what to do about it seems premature. That is the real risk of denial. So when conversations get heated, and someone calls you a name like 'denier', understand what you are denying and why the other person has become frustrated.

    And if it's me, I apologize in advance.
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  45. @John Cook:

    How do the concepts that you have presented in the above article mesh with your May 30 article, “Are you a genuine skeptic or a climate denier?” ?
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  46. "Where they disagree is on how sensitive the climate is to those CO2 emissions and that energy imbalance. They think it won't result in a large temperature change. But they don't deny that CO2 is a GHG." says Dana1981 in #42.

    It remains a contradiction in terms. GHG implies climate sensitity. You can't call a gas a GHG then state that climate sensitivity for that gas is low or nil. That's like stating sun and moon exert gravity whereas tides are caused by anything but gravity. In other words I would like to change 'sophistication' into 'sophistry'.

    For Dikran Marsupial #39, first remember Ockham's razor, second remember that AGW-theory estimates a warming of something between 2 and 4 K on doubling of CO2 (including H2O-feedback) and puts the effect of a 35% increase therefore at around +1 K. Now you say:

    "Many leading skeptical scientists do not say that the warming is caused by something other than AGW, just that negative feedback means that it [the warming due to AGW] is not a significant problem. "

    Question: what 'negative feedback'? (as to the 'significance' of the problem I will say nothing in this context).

    "Secondly the observations do not conform perfectly to AGW theory." - Actually they do. The observations fall quite in the middle of all bona fide theory and model estimations, from Arrhenius 1904 (but not 1986) to the models I encountered during my university years (meteorology/oceangraphy, indeed)as from the middle eighties until today. They do so even in details re distribution of temperature increase re latitude and height.
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  47. Alex C @21:

    If "skeptics" want to be known as real skeptics then they ought to do exactly what a real skeptics does, which is look at the entire body of evidence. Otherwise they are (as Tamino has been putting to good use) "fake skeptics," or "deniers" as so often the shoe fits.

    You are dead on. What I always ask a denier is if they've read the actual IPCC report (I'm not a scientist, BTW). Typically I get an answer like "the IPCC is a biased political organization with an agenda ... ." That's denial, not skepticism. A few better versed deniers will jump on trivial errors like the Himalayan Glaciers. I ask them if they're so sure it's wrong how come no one has documented all the flaws, page by page, line by line, including citations of the errors in the peer reviewed literature, even though they've had 4 years to do that. At that point the best I get is non-scientific nonsense writings on the Internet.

    So here's my take: if you're so sure that the 5,000+ peer-reviewed papers and hundreds of skilled research scientists who read and analyzed them to put together the IPCC report are wrong, but no one can be bothered to dissect that document to show where it's wrong, then you're a part of the denial community, not the skeptic community.
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  48. "You can't call a gas a GHG then state that climate sensitivity for that gas is low or nil."

    Sure you can. All you have to do is show that there is a strong negative feedback associated with a rise in temperature which will act to minimize any forcing from a rise in GHG's. Most of the more sophisticated "skeptics" accept the base 1.1*C or so of warming from a doubling of CO2. Where they differ from most climate scientists is in claiming that the net feedbacks from this 1.1*C rise is negative or close to it. Now, the evidence is strongly against such a low sensitivity, but the that doesn't mean that there is a logical contradiction involved in accepting the greenhouse effect and a low climate sensitivity.
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  49. Here’s yet another confirmation about the the direct reltionahip between one’s poliitical ideology and one’s views on cliamate change.

    When it comes to views on global warming, Oregonians are living in "separate realities" based on political ideology, a new online survey indicates.

    Source: “On global warming, Oregonians see 'separate realities,' survey finds,”, Sep 26, 2011

    To access the entire article, click here.
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  50. As far as the word "denier" goes, I found an approach that works on my site - I ask the person who complains about the word if they'd prefer the synonym "rejectionist" instead. I've never had someone come back and say "sure," or respond at all for that matter.

    To me this suggests that the complaint about "denier" was an attempt to claim the mantle of victim and/or was issued by a troll who was trying to divert the course of discussion.
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