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These are the best arguments from the 3% of climate scientist 'skeptics.' Really.

Posted on 25 July 2016 by dana1981

When I give a presentation and mention the 97% expert consensus on human-caused global warming, I’m often asked, “what’s the deal with the other 3%?”. These are the publishing climate scientists who argue that something other than humans is responsible for the majority of global warming, although their explanations are often contradictory and don’t withstand scientific scrutiny.

A few months ago, the world’s largest private sector coal company went to court, made its best scientific case against the 97% expert consensus, and lost. One of coal’s expert witnesses was University of Alabama at Huntsville climate scientist Roy Spencer - a controversial figure who once compared those with whom he disagreed to Nazis, and has expressed his love for Fox News.

Last week, Spencer wrote a white paper for the Texas Public Policy Institute (TPPI) outlining the contrarian case against climate concerns. TPPI is part of the web of denial, having received substantial funding from both the tobacco and fossil fuel industries, including $65,000 from ExxonMobil and at least $911,499 from Koch-related foundations since 1998, and over $3 million from “dark money” anonymizers Donors Trust and Donors Capital Fund.

Spencer’s arguments should of course be evaluated on their own merits, regardless of who commissioned them. However, it turns out that they have little merit on which to stand. The white paper is a classic example of a Gish Gallop – producing such a large volume of nonsense arguments that refuting all of them is too time-consuming. NASA Goddard director Gavin Schmidt rightly described Spencer’s paper as:

A great example of how making nonsense arguments undermines his whole point. Sad! 

A mishmash of myths

Most of Spencer’s white paper consists of repeating a variety of long-debunked myths. It’s laid out in the form of 13 basic climate questions that Spencer tries to answer. Fortunately, has a database of over 200 climate myths, and summaries of what the peer-reviewed scientific research says about each. This makes it possible to handle Spencer’s 13-point Gish Gallop by simply referring to the relevant myth rebuttals. So here we go:

1) ‘Carbon dioxide is a trace gas’ is rebutted as Myth #127.

2) ‘Climate has changed before’ is addressed in Myth #2, and climate scientistMichael Mann recently rebutted the myth that climate researchers ignore natural factors. Spencer’s misleading claims about temperatures of the past 2,000 years based on a paper by Henrik Ljungqvist are refuted in Myth #168. Claims of hotter periods during that time than today are tackled in Myth #56, and implications that the planet is magically warming because it used to be colder during the Little Ice Age in Myth #32. Finally, the rebuttal to Myth #136 explains why we can’t just blame global warming on natural cycles.

3) The reliability of global temperature measurements is explained in Myth #6.

4) Models used by the IPCC have accurately predicted global warming, as explained in the rebuttals to and Myth #229, as well as an important paper published last year.

5) The net negative consequences of rapid global warming are outlined in the rebuttal to Myth #12.

6) The warming over the past 18 years is discussed in the rebuttal to Myth #7, and is clear from the record hot temperatures of the past 3 years.

7) The accuracy of climate models is covered under Myth #5 and in my book.

8) The sensitivity of the climate to the increasing greenhouse effect is addressed in Myth #30, and the role of clouds inMyth #143.

9) False claims about the 97% expert climate consensus are in Myth #3 and Myth #226.

10) Claims of ‘slow’ ocean warming are refuted by the fact that it’s accumulating heat at a rate equivalent to 4 atomic bomb detonations per secondconsistent with climate model predictions.

11) Spencer downplays the importance of our repeated breaking of temperature records, but we wouldn’t be breaking them without global warming.

12) On climate change causing extreme weather (Myth #41), Spencer suggests that we shouldn’t worry about stronger hurricanes (Myth #16), denies the record intensity of California’s current drought, and cherry picks sea ice (Myth #157) and snow cover data (Myth #159).

13) Spencer ends his paper with the claim that the 97% of climate research that’s consistent with the expert consensus is all politically biased. This is ironic given that Spencer has previously said:

I view my job a little like a legislator, supported by the taxpayer, to protect the interests of the taxpayer and to minimize the role of government.

The best case against climate concern is really bad

All in all, Spencer managed to cram about 24 climate myths into a 13-point white paper. Most importantly, as Schmidt noted, the bulk of those myths served no purpose. 

Just consider Spencer’s very first argument. No scientist should ever claim that carbon pollution is benign because it’s only present in the atmosphere in trace amounts. For example, arsenic can be deadly if present in trace amounts in water; Spencer probably wouldn’t drink from a water source with 400 ppm of arsenic. This is an easily-refuted, scientifically-useless argument whose sole purpose seems to be fooling non-experts. It’s the climate version of the Chewbacca defense.

South Park’s “Chewbacca Defense”

Click here to read the rest

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Comments 1 to 16:

  1. Gavin, thank you again for a cogent summary of a tremendous body of work by thousands of scientists.  

    Now I only fear the most damaging, it is a yet un-numbered myth:  That we can ignore this, or somehow, temporarily disregard facing the problem.   

    Temporary denial, is still denial - and as psychotherapist Betty Merton said, "Of all the ways to deal with a problem, denial is the least effective."

    Like going to the dentist, or seeing a doctor because of a pain that will not go away  - now we are in the acting mode.  We have the information and we are feeling the pain.   Time to alleviate and mitigate. 

    We have all changed our lightbulbs, now the smallest task is to vote and/or support a candidate who is aware of the problem.  Most politicans are sinfully unaware, or misinformed.  (just my survey of a few state legislators, someone needs to do a study of this)  And we have to tell them to face it.  We must exhort everyone - especially leaders and manager - to face the facts and engage with the battle directly. 

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  2. Thanks for an interesting article. Clearly Spencers case is without substance, and all those arguments have been debunked.

    Spencer has made a mish mash of multiple arguments, including some very silly arguments. This just weakens his case, and makes it look as though he has no one point he really believes in, and is just throwing everything at the issues hoping something will stick, or the sheer volume will create doubt. Therefore his presentation has no credibility to me. It certainly totally fails to get us any nearer the truth about anything.

    The only sceptical point that deserves consideration is climate sensitivity, as we are not 100% sure. However the weight of evidence suggests it is moderate to high and the paleo climate evidence is compelling.

    The small number of studies suggesting it is low are based on the slower period of warming from roughly 2002 - 2014 and are arguing that this slow rise shows climate sensitivity is low as either the greenhouse effect is not a strong as thought, or is overwhelmed by natural variation.

    However this doesn't bear scrutiny. Obviously its dangerous to use a single short time frame, but the argument also falls down because recent science suggests the "pause" was largely because heat has been directed into the oceans, and this is because human aerosols have changed wind patterns. This means the pause is a temporary human caused event, unlikely to repeat, so cannot possibly be used as a basis to argue low climate sensitivity!

    Even if climate sensitivity is lower than thought, and global temperatures increase more in the 2-3 degree range rather than 6 degrees, I have an instinct that weather patterns “themselves” and ice sheet stability may be more sensitive to low rates of temperature change than thought.

    Consider that we have seen about 1 degree C of temperature increase since 1900, and ice sheets seem to be destabilising faster than early IPCC predictions and heatwaves are also ahead of predictions.


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  3. A very short way into reading 'A Guide to UnderstandingGlobal Temperature Data' by Roy W. Spencer, Ph.D. I start to question whether Roy Warren Spencer, Ph.D. is truly the author. I know the second page has a paragraph titled "About the Author" which provides a biog for Roy Spencer but, thinks, the rest of this booklet is so well packed with dubious nonsense, should we not ask whether the authorship it ascribes to itself is also dubious nonsense.

    My actual reason for questioning the authorship is based simply on a quick reading of a couple of the sections. As such my conclusion is prelimenary. My initial take on this booklet is that, as I have read a lot of drivel from Spencer in the past, the content of this booklet, the narrative, its structure, its argumentation, its vocabulary - it does not read like the same Roy Spencer!!

    Anybody else having similar thoughts?

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  4. I note that the Regina Leader Post has given Ross McKitrick right of reply to the excellent Michael Mann op ed linked above (McKitrick op ed published on Jul:25 - check the LP website).  Needs another reply from someone who is on top of the details, methinks.

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  5. Trace gas: 400 ppm of black ink will turn a 50 gallon aquarium tank of clear water dark.

    I think this is an excellent example to contradict the "trace gas" meme. Pure water is transparent to visible light, and ink turns it dark, causing it to absorb visible light. It only takes a tiny bit of ink.

    In much the same way the air, mostly nitrogen and oxygen, is transparent to infrared heat energy, but adding CO2 turns it dark to infrared, causing it to absorb infrared heat energy. It only takes a tiny bit of CO2.

    This is a very familiar effect to just about eveyone, like adding chocolate syrup to milk to make chocolate milk, or adding coloring to white paint, or dyeing Easter eggs, etc. It's just very easy to understand, adding something dark to something light makes the light thing dark.

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  6. BBYH @5, as demonstrated here:


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  7. Indeed, I once encountered someone on line who boasted about an AGW denying high school science teacher they knew who demonstrated to his students how little CO2 there is in the atmosphere by having them calculate how small a volume 400 ppmv of the school swimming pool was. I countered by suggesting that he next have his students add 400 ppmv of India ink to the school pool and report back. My suggestion didn't sit too well when I added that his students would then have learned something insightful.

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  8. BBHY @5 & others.

    As you all point out, the "CO2 is a trace gas" myth is entirely purile. Spencer is supposedly a grown-up scientist and, although suffering from deep delusions, he is fully signed up to CO2 as a GHG and the forcing resulting from a doubling of CO2. More, he is also signed up to the temperature rise resulting from such a forcing prior to the operation of feedback mechanisms.

    So why does Spencer's 'white paper' expend 10% of its waffle on this childish nonsense proclaiming "CO2 is a trace gas"? I don't believe Spencer has resorted to this specific argument before. Indeed, the question being addressed "Does an increasing CO2 level mean there will be higher global temperatures?" is not even answered but left with a "suffice it to say" comment which makes this section of the White Paper entirely propagandist in nature. Thus I brand it anti-scientific. Such a blatant level of disregard for science appears to me as a new departure for Spencer, assuming Spencer is the true author.

    (Unlike some other phrases in the White Paper, that "suffice it to say" phrase is encouraging for Spencer-as-the-author in that the phrase is a Spencerism eg. as per this following Spencer quote describing the temperature of the Earth with zero GHGs, of which "trace gas" CO2 is the major not-so-temperature-dependent GHG. Note this quote also stands to demonstrate how far away this White Paper is from Spencer's usual blather. "If the atmosphere could not intercept (absorb) any of that surface-emitted IR energy, ...Suffice it to say the Earth would probably be too cold for most life as we know it to survive." )

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  9. Technically, any gas that occupies less than 1% volume of the Earth's atmosphere is a trace gas. The statement itself is correct but irrelevant in the context of climate change.

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  10. Not all skeptics of climate models deny that the trace gas CO2 is a significant GHG and directly capable of about 1.1deg C warming. Rather some debate the sensitivity of Earth's climate to changing the abundance of CO2 and other GHG because of uncertainties about the feedbacks that define most of the IPCC anticipated global warming (Base Case- say A2 scenario). Your consensus argument is problematic to me. Science is dynamic and so are scientists views (hopefully), and thus the claim of certainty in climate science is also dynamic. Even if there is certainty now, new data could introduce uncertainty as it guids us towards reality.

    Currently, climate sensitivity is being challenged by data because Galactic Cosmic Rays (GCR) seem to keep emerging as a valid mechanism for forcing climate (3 recent papers below). This is significant because the sun spot number (SSN) is a valid proxy for solar activity (2), which includes TSI and magnetic field strength. The sun's pattern as observed in an 11 year running average of SSN shows that the sun's activity more than doubled from 1900 to 2000, and the absolute value of the slope of the trend was just under 3x as great from 1900 to 1950 as the negative trend was from 1950 to 2000. Currently, we are decending from the sustained solar maximum into a solar minimum. Your list above avoids this, and seems more a strawman argument by suggesting one man's opinion represents that of skeptics (Mann's link to an article about natural climate change says little about data and nothing about new insights into GCR). This page seems to also ignore the potential for the same sort of lags for solar activity that science envokes for the hiatus in explaining less antartic warming than anticipated or the hiatus.  

    I have almost no doubt that humans are causing significant global warming from GHG plus the feedbacks (as indicated in the papers below). In my own unpublished (for fun) models, I can not recreate global temperature data (HadCrut4) without significant AGW. For me, it is an invalid position to deny this. However, the body of literature for GCR forcing climate indicates to me they are 'likely' a climate forcing mechanism despite what the IPCC suggests, and to be fair several key papers have been published about GCR and solar activity's role in climate since the last IPCC publication. Also, there remains significant uncertainty about how much influence GCR and solar activity play in climate, there remains uncertainty if they play a role at all. However, there are valid questions lurking in the data:

    What is the threshold for literature about GCR to actually be considered in an IPCC climate model? Do you really think the current assemblage of climate models has the low case confidently in its range? What happens to the IPCC and climate researcher credibility if we enter a significant Maunder like solar minimum and realize the sun is a stronger driver than in any model? 


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  11. Aaron @ 10.

    We have a consensus on climate change at this point at time and its quite a strong consensus, like the consensus on evolution or basic theories of physics. These things could of course change, but it's unlikely. 

    Regarding cosmic rays. Science requires causation and correlation and currently causation is unproven, and  over the last 50 years theres no increasing cosmic ray trend so no correlation. You must have both causation and correlation. If cosmic rays are contributing to recent warming, it looks at very low level to me at best.

    Regarding solar irradiance and sunspots. We have various different cycles, and the 11 year sunspot cycles are too short to be a factor in the longer warming trend.

    The longer sunspot / solar irradiance cycle shows a slightly falling tend over the last 50 years, so theres just no correlation. The affect of solar irradiance on temperatures is pretty instantaneous, so its hard to see how current temperatures would relate to increases in solar irradience over the early part of last century. The main potential feedback mechanism would be release of CO2 from the oceans, however the oceans have basically been acidifying from early last century so any feedback would probably be quite small. 

    So it's hardly surprising that most published science says all or nearly all recent warming is from CO2. Obviously there are also certain atmospheric changes which implicate CO2, such as nights warming faster than days, etc.

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  12. Aaron S @10 . . . as an extra note for readers :- Aaron, in the "CERN CLOUD experiment" thread you had also mentioned (in more detail) some hypothesized effect on climate by Galactic Cosmic Rays.

    In the same CERN thread, other posters refuted that hypothesis, also in more detail.

    It seems evident that Cosmic Rays have little or no effect on climate changes.

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  13. As a layman, and non native English speaker, I have a question for the well read to which I haven't yet found an answer on this site: The Earth with its magnetic field is a giant electric dynamo floating in the open electric environment of the solar system which is not separated from the electrical environment of the galaxy. Furthermore, the vacuum of space is a plasma filled environment with loose electrons and electric potentials do generate current flows over intergalactic distances. (This is not even controversial.)

    The physical parts of the Dynamo heat up depending on the intensity of this flux, and science does already know that voltage potentials in the sun-earth space vary with time. Wouldn't it be scientifically prudent to atleast send probes out to verify how this variable changes over time at various points in the solar system and outside of the solar system in our small branch of the galaxy? 

    Compared to this large potential for external forcing (pun intended), and various interacting cycles -which might depend on the relative position and movement of our earth within and through this field of electric potentials-, CO2 and for that matter all other earth based variables might just be overqualified and overweighted. 

    Is this potential mechanism actively being researched? I would like to know how climate science has refutiated that hypothesis because it just 'feels' like something you would need a well researched answer to, taking into account various cycles. Do they even keep an open mind to that possibility or just turn a blind eye to it? 

    Kind regards.

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  14. eljoris @13, any "current flow" in space is in the form of the passage of positive (typically protons or ionized helium nuclei) or negative particles (typically electrons).  As such, in the vicinity of the Earth, such currents are experienced as components of the solar wind, or galactic cosmic rays; and the energy of the "electrical current" is just part of the energy contributed by those sources.  Both have been quantified, with cosmic rays contributing approximately 0.0000032 W/m^2, and the solar wind contributing a relatively "massive" 0.00035 W/m^2.  These figures include the energy from the particles physical impact, along with that from any current they carry.  For comparison, the total anthropogenic forcing increased by about 1.8 W/m^2 from 1880 to 2010, ie, approximately 560,000 times the energy recieved from cosmic rays, and 5000 times the energy received from the solar wind.  Because these energy sources are so small relative to the normal forings (changes in solar output, volcanism, anthropogenic forcings) they are neglected by climate scientists.

    Cosmic rays may have a secondary effect in which they influence cloud albedo and cloud greenhouse effect.  Current evidence suggest that any such effect is small, but potentially much larger than any direct energy effect.  Climate scientists certainly pay attention to this possibility. 

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  15. How does Roy Spencer reconcile raising his first point (trace gas) in the White paper with his blog article "Skeptical Arguments that Don’t Hold Water" from 2014?

    Spencer is pleading with fellow deniers not to embarrass themselves with these claims. The first 7 of his of 10 examples are various attempts to deny that CO2 causes warming:

    1. There is no greenhouse effect.
    2. The greenhouse effect violates the 2nd law of thermodynamics.
    3. CO2 can’t cause warming because co2 emits IR as fast as it absorbs.
    4. CO2 cools, not warms, the atmosphere.
    5. Adding co2 to the atmosphere has no effect because the CO2 absorption bands are already 100% opaque.
    6. Lower atmospheric warmth is due to the lapse rate/adiabatic compression.
    7. Warming causes co2 to rise, not the other way around

    Yet surely by posing the old "trace gas" nonsense he is making exactly the claim that "there is no greenhouse effect"?

    Am I missing something, or is Spencer?

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  16. I've been asking myself why this "trace gas" claim keeps popping up.

    I believe that it appeals to two unspoken arguments:

    1. Obviously, the basic claim is that no substance can have a significant effect if it is only present in small proportions; or else that substance have effects in direct ratio to the their proportion in a mixture or system. The many counterexamples effectively refute that.

    2. There may be a further unspoken belief: that the effect of a trace substance must be diluted by the other elements of compounds present, in proportion to their relative amounts. So the intuition is that all the nitrogen or oxygen in the atmosphere must dilute the effect of CO2 until it is negligible.

    Now the second intuition is completely contrary to physics. Molecules of gases which do not absorb and re-emit IR do not interfere with the ability of greenhouse gases to do so. And as somebody mentioned on SKS, the real question is not the percentage or ppm of CO2, but how many atoms of it are present , and how likely and IR is to encounter them.

    There is an interesting parallel between the second "dilution" form of the false intuition with sceptical arguments against Darwin in his own day.. Perhaps the best objection (except perhaps Kelvin's?)that Darwin encountered in his lifetime to his theory of natural selection was that traits ought to become more and more diluted as they were "mixed" during reproduction. Thus selection should break down, because there could be no reliable transmission of traits.

    We know now that the correct answer to this was already printed, unnoticed in a paper by Gregor Mendel; genetics shows that traits don't blend like colours in a mixture.

    Now these sceptical replies to Darwin were not denialism at that time, because they were raised as part of a rational scientific scepticism. If the same arguments are posed today by creationists, they are just not scepticism but just PRATTs - Points refuted a Thousand Times".

    In the same way, almost every one of the denialist myths refuted here was once a reasonable hypothesis that needed to be considered carefully and tested. As they have been. But once they have comprehensively refuted, to keep resurrecting them as zombies is quite different from any genuine scepticism.

    I wonder in passing whether it would be worth analysing the denialist project in the light of Imre Lakatos's distinction between progressive and degenerating research programs

    It would be interesting to trace the history of this process, and find out how many objections were tested and refuted by those climate scientists who pioneered the field, and how many (or few) genuinely arose from the so-called "skeptics".

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