97% vs 99.99%

We’ve just had another consensus paper published. The paper is called Does It Matter if the Consensus on Anthropogenic Global Warming Is 97% or 99.99%? (pre-print here). The lead author is Andy Skuce, who has a nice post about it. Dana Nuccitelli is also one of the authors and has written a Guardian article.

Our paper is mostly a response to a paper by Jim Powell, which concludes that Climate Scientists Virtually Unanimous, claiming

the consensus on AGW among publishing scientists is above 99.99%, verging on unanimity.

Powell’s paper also claims that the Cook et al. (2013) 97% was obtained by ignoring a large number of papers/abstracts (those that took no position) which Powell argues should be rated as endorsing the consensus. His paper also claims that the Cook et al. method would return a nonsensical result if applied to a topic for which their is actual unanimity (plate tectonics, for examples) – it would lead to, Powell claims, dividing zero by zero.

Dana and Andy’s articles (linked to above) provide very clear explanations of our response, so I don’t need to say much. One issue is simply related to defining what’s being determined. Powell determined what fraction of abstracts/papers rejected anthropogenic global warming (AGW) and concluded that the rest endorsed it. Cook et al., however, established what fraction of abstracts that took a position with respect to AGW, endorsed that humans are causing global warming. Powell, therefore, gets that 99.99% of abstracts/papers don’t reject AGW, while Cook et al. conclude that just over 97% of abstracts/papers endorse that humans are causing global warming. These are not quite measuring the same thing. In fact, if you apply Powell’s method to the Cook et al. data, you also get that more the 99% do not explicitly reject AGW.

Powell’s claim that Cook et als method would return a nonsensical results for a topic about which there is unanimity is simply wrong. Cook et al. rated papers as to whether they took a position, or not, and – if they took a position – if it was explicit or implicit. The consensus was then the fraction of papers that took a position, that endorsed (implicitly, or explicitly) the consensus. Even if explicit endorsements are unlikely for topics about which there is unanimity, a reasonable fraction of papers/abstracts still implicitly endorse the consensus. We tested this in our paper using plate tectonics as the topic, and did indeed find that a reasonable fraction of abstracts do indeed implicitly endorse the plate tectonic consensus. Of course, none reject the consensus (explicitly, or implicitly) and so the computed consensus is – as expected – 100%.

One could argue that maybe it doesn’t make much difference if the consensus is 97%, or 99.99%; it’s still almost all. Personally, I think it is important to be clear about what is actually being determined; the 97% and 99.99% are determining slightly different things. Also, that 99.99% of abstracts/papers do not reject AGW does not tell you what fraction endorse the stronger position that humans are causing global warming. The result does depend on what position is actually being tested – and whether you assess papers, abstracts, or people – but if you consider relevant experts, or the relevant literature, you find that more than 90% agree that humans are causing global warming. Showing that more than 90% (and typically around 97%) endorse that humans are the dominant cause of global warming, seems stronger than showing that virtually all accept some human contribution. Of course, the latter is still a very useful metric as it does show that explicitly rejecting AGW is now extremely rare.

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80 Responses to 97% vs 99.99%

  1. Joshua says:

    A somewhat interesting read on the issue of “consensus.”

    Learning To Love Scientific Consensus

  2. Joshua says:

    Personally, I ALWAYS go with what Richard Tol has to say.

    “Published papers that seek to test what caused the climate change over the last century and half, almost unanimously find that humans played a dominant role.”

    That seems to me to be good enough approximation to be workable.

  3. Joshua,
    Interesting article about people being ridiculed for holding views at odds with the consensus. Seems to produce a result that seems reasonable; sometimes true, but mostly it’s either a field that doesn’t really have an over-riding consensus, or it just takes some time for the new idea to prove itself (which is kind of how science is meant to work).

    Personally, I ALWAYS go with what Richard Tol has to say.

    So do I, of course.

  4. Michael E Fayette says:

    Why does this question even matter? It is obviously the wrong question, phrased badly.

    It is obvious to anyone who has a ounce of knowledge that human activities DO have the potential to contribute to global warming (and perhaps cooling too!) As a species, we are now numerous enough to have real impact with land use, pollution, nuclear energy, contrails, CO2 emissions, etc….

    No one seriously doubts this fact and the difference between 97% and 99.9% is meaningless.

    The question – of course – is how MUCH of our current warming is due to humans?

    And how much of FUTURE warming might be due to us?

    I doubt there is anything like 97-99% consensus on the answer to this question, and IT WOULDN’T MATTER IF THERE WERE such a consensus. It only takes one contrarian theory by a single individual – after his/her predictions are tested and found true – to completely change the “consensus” of everyone else.

    Seek truth – not votes…..

  5. Michael,

    The question – of course – is how MUCH of our current warming is due to humans?

    It’s almost as if you didn’t read the post – the difference between the 99.99% and 97% is essentially that one does not say much about the actual human contribution and the other does. Of course, consensus studies do not actually quantify this. However, analyses that do show that it is extremely likely that more than 50% of the observed warming since 1950 was anthropogenic, and that the best estimate is that the anthropogenic contribution is similar to the observed warming. See, here, for example.

  6. Powell’s paper also claims that the Cook et al. (2013) 97% was obtained by ignoring a large number of papers/abstracts (those that took no position) which Powell argues should be rated as endorsing the consensus. His paper also claims that the Cook et al. method would return a nonsensical result if applied to a topic for which their is actual unanimity (plate tectonics, for examples) – it would lead to, Powell claims, dividing zero by zero.

    You have shown that this argument of Powell is wrong. The 97% is a reasonable and defensible estimate. I would argue that the 99.99% estimate of Powell is also defensible. Also using Powell’s method you find the right answer for plate tectonics: 100%.

    These were not just climate papers, but papers about global warming. If the authors would have rejected the consensus, this would in many cases have influenced how they performed a study on global warming, at least a bit. If they were confident they had good evidence that the consensus is wrong, you would expect them to mention this.

    The 97% is likely too low, the 99.99% is likely too high, but both are defensible, especially after explaining how it was computed.

  7. Victor,

    The 97% is likely too low, the 99.99% is likely too high, but both are defensible, especially after explaining how it was computed.

    Quite possibly. I should have added that you also expect the consensus to strengthen over time. Cook et al. considered 1991-2011, while Powel considered 2013 and 2014. If you applied Cook et als method to Powell’s data you would probably get more than 97%, but less thn 99.99%.

  8. I had to check, but yes, Argumentum ad Populum is still a logical fallacy.

    Now, at least the consensus above is specific.

    I believe that humans are [probably] causing global warming.
    But if it is so, it is not so because I or anyone else believes it, but rather because of the demonstrable radiative physics that could be but are not likely to be obviated by other processes.

    However,
    global warming is not the same thing as climate change,
    and climate change is not the same thing as net detrimental climate change,
    and net detrimental climate change is not the same thing as catastrophic climate change

    I don’t know what the consensus is on catastrophe, and fortunately, it doesn’t matter, because neither the physics nor the observations support catastrophe.

  9. TE,

    I had to check, but yes, Argumentum ad Populum is still a logical fallacy.

    Who made such an argument?

  10. I haven’t followed this, so it’s entirely legit to say “Read the papers,” but as a proportion is being estimated and being a Bayesian I’d ask what the 95% Highest Probability Density Interval contains rather than, say, a point estimate like the mean. I might also suggest such proportions, if there’s an insistence upon point estimate, might be better expressed as an odds ratio . Both these could avoid distinctions between 0.97 and 0.99 or 0.95. The trouble is the marginal amount of information need to push the estimate from, say, 0.93 to 0.95 is a lot less than that needed to go from 0.95 to 0.97. That’s a problem with proportions: They rarely faithfully convey amount of evidence. Odds do it better.

  11. Who made such an argument?
    The subject of the papers indicate a belief that consensus is significant.

    Q: Does It Matter if the Consensus on Anthropogenic Global Warming Is 97% or 99.99%?
    A: No. But it doesn’t matter if the consensus on AGW is 0%, either.

    Consensus has no bearing on validity, veracity, or falsifiable predictions.

  12. TE,
    Maybe you can try one more time. Who has made an argumentum ad populum? Just for clarity, this is an argument which claims that something is true because many people believe it.

  13. Joshua says:

    TE –

    =={ The subject of the papers indicate a belief that consensus is significant.

    Q: Does It Matter if the Consensus on Anthropogenic Global Warming Is 97% or 99.99%?
    A: No. But it doesn’t matter if the consensus on AGW is 0%, either.

    Consensus has no bearing on validity, veracity, or falsifiable predictions. }==

    Consensus is significant, in that it is a way that people who don’t understand the science can evaluate probabilities. It is a common heuristic that people use in such circumstance – I’m quite sure that you do it in a lot of circumstances, as do all “skeptics” when they haven’t wrapped up their identity into the question of whether one exists.

    The problems arise when: (1) people argue that the existence of a consensus is dispositive and, (2) people argue that the existence of s consensus is irrelevant or, (3) people argue that considering the existence of a consensus is antithetical to practicing the scientific method.

    Oy. Another thread arguing about “consensus?” The fact that the argument about the consensus is so widespread and so persevering is what is the most interesting aspect of the consensus, IMO. Because it goes to show how much interest there is in discussing issues that have nothing directly to do with the science.

  14. Willard says:

    > I had to check, but yes, Argumentum ad Populum is still a logical fallacy.

    Perhaps you missed that bit from the Wiki you cite, TE:

    Appeal to belief is valid only when the question is whether the belief exists. Appeal to popularity is therefore valid only when the questions are whether the belief is widespread and to what degree. I.e., ad populum only proves that a belief is popular, not that it is true. In some domains, however, it is popularity rather than other strengths that makes a choice the preferred one, for reasons related to network effects.

    https://en.wikipedia.org/wiki/Argumentum_ad_populum#Exceptions

    From C13’s introduction:

    Despite these independent indicators of a scientific consensus, the perception of the US public is that the scientific community still disagrees over the fundamental cause of GW. From 1997 to 2007, public opinion polls have indicated around 60% of the US public believes there is significant disagreement among scientists about whether GW was happening (Nisbet and Myers 2007). Similarly, 57% of the US public either disagreed or were unaware that scientists agree that the earth is very likely warming due to human activity (Pew 2012).

    Through analysis of climate-related papers published from 1991 to 2011, this study provides the most comprehensive analysis of its kind to date in order to quantify and evaluate the level and evolution of consensus over the last two decades.

    http://iopscience.iop.org/article/10.1088/1748-9326/8/2/024024

    Thanks for playing.

  15. JCH says:

    What you just might have here is an argumentum ad odium. After all, climate scientists like Mann and advocates like Al Gore made them hate climate science even if it is right.

    Or, we made them violate Judy’s blog rules. Over and over. Like, thousands and thousands of times.

  16. Marco says:

    “I don’t know what the consensus is on catastrophe, and fortunately, it doesn’t matter, because neither the physics nor the observations support catastrophe.”

    That depends on what one would consider a catastrophe. Consider for that the global panic during the financial crisis. I didn’t consider it a catastrophe myself, but I know someone who literally jumped off a high building because of what happened.

  17. Marco,

    That depends on what one would consider a catastrophe.

    Indeed, neither the physics nor the observations rule out changes that most (but maybe not TE) would agree would probably have catastrophic impacts.

  18. Marco says:

    I’d say it different: in the view of some people a catastrophe is *already* happening (e.g. the changes in the arctic).

  19. Indeed, and the Great Barrier Reef.

  20. Andy Skuce says:

    TE:
    “Q: Does It Matter if the Consensus on Anthropogenic Global Warming Is 97% or 99.99%?
    A: No. But it doesn’t matter if the consensus on AGW is 0%, either.”

    I’ve got a feeling that if the scientific consensus on AGW was zero, there would be changes to public policy. Yes, of course, that consensus would not prove that humans do not play a dominant role in global warming—the consensus has been wrong before!—but I doubt that conservatives would still be making claims that we should avoid the logical fallacy of employing ad populum arguments.

  21. “I’d say it different: in the view of some people a catastrophe is *already* happening (e.g. the changes in the arctic).”

    Ideally, it is the future net of benefit and detriment we should consider with respect to increased CO2. Anyone interested in this topic probably has blinders as to both benefits and detriments, and I’m not an exception.

    But, with that in mind, I will offer this:
    Arctic Amplification of warming tends to moderate climate.
    Because AA exerts bottom-of-the-atmosphere forcing out of phase with seasonal forcing, it tends to reduce the pole to equator temperature gradient in the Northern Hemisphere. This implies 1.) reduced kinetic energy, and 2.) reduced temperature variability. The effect may not be large, but the physics are sound.

    “Indeed, and the Great Barrier Reef.”
    Coral are indeed sensitive to high ( and low ) temperature anomalies.
    But be careful of confirmation bias when considering this in terms of global warming.
    There is a long list of factors which cause coral death.

    Two of those factors are co-incident with temperature.
    Low sea level kills coral by leaving them above water and exposing them to air for too long.
    But low tropical sea level also coincides with higher temperatures (reduced mass & circulation).
    Too much sunshine also kills coral.
    But increased sunshine also coincides with higher temperatures.

    The fact that coral have existed for half a billion years, a duration which has incurred all ilk of climate variability, should be some indication that they are not as fragile as made out. Further, include on the list of considerations of coral that they are symbiotic and depend on photosynthesis. As with land based plant life, coral benefit from having more available CO2 to photosynthesize.

  22. TE,

    Ideally, it is the future net of benefit and detriment we should consider with respect to increased CO2.

    I think people are perfectly entitled to regard something as catastrophic even if some economic analysis suggests that there might be some kind of net benefit.

    There is a long list of factors which cause coral death.

    I think I’ll go, for the moment at least, with Terry Hughes, who says:

    The three main drivers of degradation are pollution, overfishing, and, increasingly, climate change.

    You also say:

    The fact that coral have existed for half a billion years, a duration which has incurred all ilk of climate variability, should be some indication that they are not as fragile as made out.

    That corals may well adapat and recover, does not somehow mean that we shouldn’t be concerned with what is happening now.

  23. verytallguy says:

    TE

    The fact that coral have existed for half a billion years, a duration which has incurred all ilk of climate variability, should be some indication that they are not as fragile as made out.

    This is complete and unadulterated essence of bullshit, use the technical term.

    pseudo-profound bullshit, which consists of seemingly impressive assertions that are presented as true and meaningful but are actually vacuous

    Click to access jdm15923a.pdf

    That corals as a species have survived for half a billion years has no bearing whatsoever on whether the current reef ecosystem could be catastrophically damaged by AGW.

    In the same way that the existence of mammals does not indicate that the end cretaceous impact failed to have a catastrophic impact on their population at the time.

  24. The Very Reverend Jebediah Hypotenuse says:

    TE:

    I don’t know what the consensus is on catastrophe, and fortunately, it doesn’t matter, because neither the physics nor the observations support catastrophe.

    Easy for you to say.

    None of the people typing comments here today will see the full effects of our
    cumulative GHG emissions.

    Hey, TE!!!
    Your descendants just called – They want to use “your” physics and observations to prove that the smoke-enshrouded, polluted, resource-depleted, ecologically barren cinder that they live on is only a liberal illusion…!

  25. Marco says:

    Two things, TE:
    First, the biotope of the arctic has already changed to an extent that people, animals and plants living there start to notice. Some humans see their way of life threatened by this, and thus consider it already a catastrophe in process. We don’t quite know what the animals and plants are thinking, but if they could, I doubt many will be happy to hear that it may be good for people elsewhere.

    Second, your comment that “The fact that coral have existed for half a billion years, a duration which has incurred all ilk of climate variability, should be some indication that they are not as fragile as made out.” is BS for more reasons than the ones VTG points out. For example, there have been several extinction events in that 500 million year history. As a result of extinction events, there have been very long periods of time where there were no coral reefs. As in “likely none at all”. Over periods of 50-100 million years, even. As a result, the current coral species (note: plural) are not the same as those from 50 million years ago.

    Sure, the earth will survive, and corals will likely come back, but when? And what will all those species do that relied on those coral reefs? They will have to try and adapt. If they can’t, they will die out, too. Some people will consider those extinctions catastrophic. Others may be happy if the angelfish die out…

  26. JCH says:

    But be careful of confirmation bias…

    Why be careful? You’re not.

  27. But be careful of confirmation bias… — Why be careful? You’re not.

    You’re being ironic again, right?

    The recent GBR event was maximal on the Cape York Peninsula:
    https://sealevel.nasa.gov/internal_resources/58

    El Ninos cause low sea level over the coastal NorthEast of Australia.
    And there’s evidence that the coral death related to low sea level preceded the high temperatures which also occur during El Nino events.

    Here’s the animation of sea level for the recent event and the 97/98 event.
    Watch the Cape York Peninsula.

  28. TE,
    Just to be clear, are you actually suggesting that the recent bleaching was mainly due to the sea level change from the El Nino?

  29. TE,
    Just in case you are promoting Jim Steele’s sea level ideas, here – again – is what Terry Hughes has to say:

    “Steele needs to actually read our Nature paper. We reported the extent of bleaching, measured both from the air and underwater — the latter on 150 reefs.

    Mass bleaching due to thermal stress is the only mechanism that can turn more than 1000km of a reef system white in the course of a few weeks.

    In the Nature paper, we show the relationship between thermal stress experienced on each reef and the amount of bleaching recorded underwater by divers. We also ground-truthed the accuracy of the aerial scores, and found them to be highly reliable.

    We also showed that satellite measurements of heat exposure matched the aerial bleaching scores as well as the underwater scores. The south didn’t bleach in 2016 because it was cool, the north was the most severely bleached because it was hottest

  30. Ethan Allen says:

    So if you can get the 97% consensus message out (without mentioning the “so called” consensus gap, because if you did that, you just might confuse billions of Earth’s “so called” village idiots) to all 100% of Earth’s people (in a manner very similar to all surveys listed in said paper, e. g. a very short time slice where the responses have to go up, given the nature of such testing (jeez, you showed me a pie chart of 97% and I just couldn’t remember or purposely give the wrong answer)) …
    Good luck with that one, as I hear the 97% (in passing on the teevee) or read the 97% (in passing in print or online articles) all the time, but no one dwells on that particular statistic, for more than a few seconds, in most of the MSM I have seen to date.
    The other major factor lacking from all testing shown to date in said paper is loss of retention of information over time, I doubt that the immediate time statistics would hold up over time as most people have a tendency to forget stuff, particularly stuff that isn’t a major factor in their lives to begin with in the 1st place. Good luck on that one too.

  31. John Hartz says:

    TE: Something for you to chew on….

    Climate change may now be a part of the gentrification story in Miami real estate

    High Ground Is Becoming Hot Property as Sea Level Rises by Erika Bolstad, ClimateWire/Scientific American, May 1, 2017

  32. John Hartz says:

    Etaan Allen: You can bet your sweet bippy that I’m not going to remember your comment for any significant length of time. 🙂

  33. JH: Looks like the folks with money still want to be on the waterfront.
    Here’s the Zillow map of $1,000,000 plus homes.

  34. John Hartz says:

    TE: More for you to chew on:

    In the mountains, trees are racing uphill to escape the heat – and in Canada, invasive insects have already killed massive swaths of forest. Such changes will have significant consequences for communities and ecosystems.

    Global warming is reshaping the world’s forests</strong by Bob Berwyn, Deutsche Welle (DW), May 4, 2017

  35. John Hartz says:

    TE: Folks with money definitely live on the waterfront in SE Florida now, but not forever as detailed in the article.

    PS – It’s always best to read an article before commenting on it. It saves the time and energy of cleaning the egg off of one’s face and the cost of the egg.

  36. Willard says:

    I think peddling watery stuff has run its course, everyone.

  37. Ethan Allen says:

    I read Dan Kahan’s mind before I wrote my previous post (sorry it’s paywalled) …

    Out of the lab and into the field
    http://www.nature.com/nclimate/journal/v7/n5/full/nclimate3283.html

    Abstract
    Decision scientists have identified remedies for various cognitive biases that distort climate-change risk perceptions. Researchers must now use the same empirical methods to identify strategies for reproducing — in the tumult of the real world — results forged in the tranquillity of their labs.

    “To the extent that cultural cognition drives climate-change risk perceptions, it is reasonable to surmise that science communication will be more effective when it disentangles disputed facts from identity-defining group commitments. These include the use of message framing(14), the credibility heuristic(15), group-identity affirmation(16), solution aversion(17), and the like. Lab studies supply reasons to think that techniques based on these results will work, and work better than ones that might have once seemed plausible but that ultimately failed, such as bolstering science literacy(8) or promoting awareness of the extent of the scientific consensus(18),(19).”

    “Lab studies will never completely lose their value. Under ideal conditions, there would be a reciprocal relationship in which lab-derived insights would be used to drive field research, which in turn would expose new questions about mechanisms, the investigation of which would require more lab studies. However, there comes a time when we know enough about general mechanisms to start the independent process of adapting those mechanisms to real-world situations. That time is now. More researchers need to be venturing forth from the lab and into the field to test hypotheses about how results observed in the former can guide decisions in the latter.”

    So I’ll say it again, good luck with “so called” in-the-field inoculation the entire world.

    See also …
    “The Strongest evidence to date…”: What the van der Linden et at. (2015) Data Actually Show
    https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2779661

  38. Willard says:

    DanK’s commentary has been cited by this paper, EA:

    What happens when competitive rhetoric is introduced that challenges a consensus statement? A common type of counter-message strategy is to politicize the underlying science; that is, when an actor exploits “the inevitable uncertainties about aspects of science to cast doubt on the science overall… thereby magnifying doubts in the public mind” (Steketee, 2010, p. 2; also see Jasanoff, 1987; Oreskes & Conway, 2010; Pielke, 2007). To cite an example – in response to the release of the Climate Change Impacts in the United States report that stated a scientific consensus exists that global climate change stems “primarily” from human activities, Florida Senator Marco Rubio stated, “The climate is always changing. The question is, is manmade activity what’s contributing most to it? I’ve seen reasonable debate on that principle” (Davenport, 2014, A15).

    Click to access WP-16-21.pdf

    A more recent example is of course our latest ClimateBall episode.

    And why yes, Virginia – honest brokers said something related to spreading FUD.

  39. Ethan Allen says:

    Yes Willard, I already have said paper, but see also …

    Communicating Science Effectively: A Research Agenda (2017)
    https://www.nap.edu/catalog/23674/communicating-science-effectively-a-research-agenda
    (Kahan (18) in previous post)

    and …

    Rational Irrationality: Modeling Climate Change Belief Polarization Using Bayesian Networks
    (Kahan (19) in previous post)
    http://onlinelibrary.wiley.com/doi/10.1111/tops.12186/pdf
    Abstract
    Belief polarization is said to occur when two people respond to the same evidence by updating their beliefs in opposite directions. This response is considered to be “irrational” because it involves contrary updating, a form of belief updating that appears to violate normatively optimal responding, as for example dictated by Bayes’ theorem. In light of much evidence that people are capable of normatively optimal behavior, belief polarization presents a puzzling exception. We show that Bayesian networks, or Bayes nets, can simulate rational belief updating. When fit to experimental data, Bayes nets can help identify the factors that contribute to polarization. We present a study into belief updating concerning the reality of climate change in response to information about the scientific consensus on anthropogenic global warming (AGW). The study used representative samples of Australian and U.S. participants. Among Australians, consensus information partially neutralized the influence of worldview, with free-market supporters showing a greater increase in acceptance of human-caused global warming relative to free-market opponents.
    In contrast, while consensus information overall had a positive effect on perceived consensus among U.S. participants, there was a reduction in perceived consensus and acceptance of human caused global warming for strong supporters of unregulated free markets. Fitting a Bayes net model to the data indicated that under a Bayesian framework, free-market support is a significant driver of beliefs about climate change and trust in climate scientists. Further, active distrust of climate scientists among a small number of U.S. conservatives drives contrary updating in response to consensus information among this particular group.

    ——————————————————————————————————————————————-

    AFAIK, your last two “so called” sentences translate to gibberish at my end. I can easily and directly understand Bernie Sanders, he has an excellent and plainly spoken demeanor. I’d suggest you attempt to communicate in a similar manner.

  40. Willard says:

    Dear EA,

    The first of the two gibberish sentences connected the emphasized bit of my quote with the Bret Stevens episode. The second sentence underlined that Pielke 2007 was cited as an authority warning against “magnifying doubts in the public mind”. Putting the two together, one should get that competitive rhetoric is something that matters quite a bit.

    Thank you nevertheless for your unsollicited advice. In return, I suggest you try syntax. It’s a Good Thing. Noam Chomsky does syntax well, or so I’ve heard. By syntax I mean stuff like emphasis (**), elision ([…]), paragraphs (two carriage returns), and boldness (no underhanded “…”). This may help you stop spamming with DanK’s stuff that is not exactly the topic of our thread. While consensus studies can attract “but DanK,” we’re not into consensus messaging. Spamming irrelevant stuff does not provide good competitive rhetoric. You can do better.

    Good luck with that.

    PS: It goes without saying that Bernie would have won all the ClimateBall arguments.

  41. JCH says:

    They ran wit the SLR diversion without checking to see if sea level had gone down over the GBR.

  42. Ethan Allen says:

    [Snip – playing the ref. Also, if you could be so kind as to keep the pseudonym under which you identify yourself in other climate sites, that’d be great. -Willard]

  43. JCH says:

    Hints…

    South Pacific:

    The El Nino sea level drop:

  44. Everett F Sargent says:

    [More playing the ref. Thank you for putting the sock back in your pocket, EA. Rest assured that AT is made aware of every snip. You can contact him. You can even contact me. -Willard]

  45. Andrew Dodds says:

    Just to clarify for some..

    Although reef-style ecosystems have existed throughout the Phanerozoic – carbonate mounds constructed by biological processes – the species assemblages building them have changed dramatically. Reefs have been constructed by coralline algae, by Stromatoporoids, by bivalves and by several different groups of corals.

    This is important, because this implies that reef building organisms have been completely obliterated on several occasions, so that their niche could be re-occupied by completely unrelated organisms. The picture that TE paints of corals existing uninterrupted for half a billion years is clearly false.

  46. John Hartz says:

    Andrew Dodds: Thanks for setting the record straight re corals.

    For the most part, ET’s posts are “throw aways” , but their false assertions do need to be challenged and corrected.

  47. Willard says:

    To return to the topic of AT’s post, I find this argument from the abstract a bit weak:

    The 3% of published papers that reject AGW are contradictory and have invariably been debunked. They do not therefore provide a coherent alternative account of climate science.

    The first premise is both trivial and irrelevant. It is trivial because it’s obvious that alternative hypotheses may conflict with one another. It is irrelevant because only a coherent subset of them could in principle replace AGW.

    The second premise introduces a word I dislike: “debunk”. In what way these papers have been “debunked” is far from clear, and that demonstration falls outside the scope of the paper. There’s no need to debunk a paper for a community to find it unconvincing.

    OTOH, the word “debunk” gives me a fairly good idea of who wrote the abstract.

  48. Willard,

    The first premise is both trivial and irrelevant. It is trivial because it’s obvious that alternative hypotheses may conflict with one another.

    I don’t think it is trivial and irrelevant. What it’s distinguishing between is a situation in which 97% agree with one position, and 3% agree with a single alternative, versus 97% agreeing with one position, and the other 3% promoting a wide range of different alternatives.

  49. Magma says:

    I’m torn. I understand the approach taken in this latest paper and comment (given the number of authors, I’ll call them the 97-percenters), but I also have some sympathy for James Powell’s approach, which is consistent with Richard Alley’s position as given in a hilarious 90 second debunking of the contrarians’ Great Climate Change Conspiracy theory in his “What drives scientists?” talk (https://www.youtube.com/watch?v=b_WLArrksB4).

    If you were a researcher with a sound, data-supported hypothesis that knocked down any core part of the GHG-driven anthropogenic climate change consensus, what could possibly stop you from presenting those results at major conferences, publishing it in leading journals, bringing your results to the media, and obtaining whatever funding you needed from oil companies?

    One can draw a very strong conclusion from the decades-long absence of such results.

    That said, the 97-percenters and the 99.99-percenters are to some extent comparing apples and oranges. The first are examining individual attitudes and acceptance of a scientific consensus, the second are drawing conclusions from published/publishable results. They are complementary, not contradictory.

  50. They are complementary, not contradictory.

    Indeed, I agree. However, there were a number of claims made by Powell about the 97% analsysis (such as it returning a nonsensical result for fields in which there is unanimity) that were wrong.

  51. Willard says:

    > What it’s distinguishing between is a situation in which 97% agree with one position, and 3% agree with a single alternative

    Sure, but you could then simply assert that the 3% does not provide a coherent alternative account of climate science. The first sentence and the “therefore” could have been omitted. It carries needless obligations.

    Removing a needless sentence from an abstract is a Good Thing. Just imagine if turbulent commentators tried to see what’s behind it. It’s always possible to ask if a paper is truly debunked. The authors might not like to put the ClimateBall hours to the debunked question.

    Looks overcommitting to me.

  52. Willard,

    The first sentence and the “therefore” could have been omitted. It carries needless obligations.

    Actually, it was. The published abstract doesn’t contain the portion of the pre-print abstract that you quoted.

  53. John Hartz says:

    ATTP: Perhaps because i’m a member of the SkS author team and have been exposed to The Consensus Project since it was a mere gleam in John Cook’s eye, my eyes tend to glaze over when I see another article about it. That said, repitition is certainly a key marketing tactic. Do you happen to know off hand how many OPs you have penned on this topic? On the “pause”? On Climate Sensitivity?

  54. JH,

    Do you happen to know off hand how many OPs you have penned on this topic? On the “pause”? On Climate Sensitivity?

    The answer is, probably, too many 🙂

  55. Willard says:

    I see it now:

    The ~3% of scientists who either dispute or are undecided about AGW do not present a coherent case against the theory and their arguments have invariably been rebutted.

    AndyS’ note on the emergence of the theory of tectonic plates shows well how it differs from the Contrarian Matrix.

  56. I see it now:

    Yes, it is still in that copy. It isn’t, however, in the published version as we had to shorten the abstract.

  57. Joshua says:

    Anders –

    From the abstract:

    =={ Nevertheless, because of the politicization of the issue, dissenters are accorded undue attention in the media and in public debate (Boykoff, 2013). }==

    Just to nitpick… I think that “undue” is a rather subjective evaluation, and thus shouldn’t be in an abstract. If you said that the attention is “disproportionate,” it would be quantifiable in some concrete way, (say, a study of media coverage could show that 3% of the scientists get 40% of the press coverage). How do you objectively quantify what amount of attention is “due?”

  58. Joshua,
    Actually, that bit isn’t in the final published version either.

  59. Andy Skuce says:

    At the last minute, in the process of the publisher reformatting the final text for publication, we were asked to cut the abstract length in half. The original, longer abstract is retained in the freely -available preprint. There are are few other minor changes to wording or formatting between the official version and the preprint version. Assiduous readers can ask me or any co-author for a PDF copy of the final version. We are free to distribute these to inviduals, but cannot post links to copies on websites.

    I’ll update the preprint with a health warning that the journal version is the definitive one and that, in particular, the abstract was significantly shortened after the editor’s acceptance of the manuscript. Sorry for any confusion, but we are trying to play by the publsher’s rules.

  60. Joshua says:

    Anders –

    Just to nitpick a bit more (I’ve got unscheduled time on my hands due to rain interfering with my planned garden work)….

    Having followed from Willard’s comments…

    FWIW, I think that the sentence regarding the lack of coherence in the 3% doesn’t fit (or flow) with the narrative of the rest of the abstract, and it doesn’t provide a logical premise for the next sentence that discusses the disproportionality of focus (i.e., the disproportionality would exist independent of whether there is a coherence. And if they 3% were coherent, would that mean that the attention would therefore be proportional).

  61. Joshua says:

    Oops. Nevermind!

  62. Andy Skuce says:

    “Undue” comes from the notion of false balance in the media documented by Boykoff (and John Oliver). Perhaps “disproportionate” would have been better.

  63. Magma says:

    Possibly, Andy, but I don’t think the original choice was wrong. The shorter Oxford definitions:

    Disproportionate (adjective)
    Too large or too small in comparison with something else.

    Undue (adjective)
    Unwarranted or inappropriate because excessive or disproportionate.

  64. Willard says:

    To paraphrase Strunk, omit needless adjectives.

    I’m not a fan of undue citation in abstracts, and Powell’s argument is best addressed by showing that only a coherent alternative account of climate science could undermine AGW. I’m sure we can find alternative theories of continental drift.

    This cuts through any discussion of percentages. Theories with no explanatory power are worthless. Only the best explanation wins.

  65. Magma says:

    I’m sure we can find alternative theories of continental drift.

    No.

  66. John Hartz says:

    Out of curiousity, did theologins ever reach consensus on how many angels fit on a pin? 🙂

    In all seriousness, the OP and much of the discussion is of the “inside baseball” variety that has very little impact on the general public’s understanding of what manamde climate change is and how it is impacting the Earth’s climate system now and in the future. In that context, perhaps it’s time to move on to other topics.

  67. Willard says:

    > No.

    Right here, Magma:

    It is now accepted that the plates carrying the continents do move across the Earth’s surface, although not as fast as Wegener believed; ironically one of the chief outstanding questions is the one Wegener failed to resolve: what is the nature of the forces propelling the plates?

    https://en.wikipedia.org/wiki/Continental_drift

    Wegener’s theory is already deprecated.

    For an historical review I found Wesson 1970 in a New York minute.

    Welcome to the Internet.

  68. Magma says:

    There’s a risk of being misunderstood if one engages in word play too often, Willard.

    I assumed that you were referring to the modern day consensus on plate tectonics rather than Wegener’s century-old continental drift hypothesis, which foundered because neither he nor proponents of his or similar hypotheses were able to come up with a viable physical mechanism by which continents could move (although Arthur Holmes came very, very close).

  69. Willard says:

    > I assumed that you were referring to the modern day consensus on plate tectonics rather than Wegener’s century-old continental drift hypothesis […]

    You assumed correctly, Magma, but there is still the possibility that people are talking past one another here. Thy Wiki tells me that the hypothesis that continents were drifting can be traced back in Ortelius 1596. Wegener developed the continental drift hypothesis with a theory postulating a pseudo-centrifugal force which has been rejected for lack of plausible evidence. This theory has now been replaced with the theory of tectonic plates.

    According to my short research, I learned that the theory of tectonic plates is still incomplete. That theory has yet to offer the very mechanism which has been found lacking in Wegener’s theory. I surmise that there are many contenders for that mechanism, which would account for all the geological phenomena we wish to explain with that theory. Something that is left unexplained should be an object of debate in a field, wouldn’t you agree?

    To complexify matters, we could shift from the theory to its various models:

    The work of Sibley (2005) raises concerns regarding the conceptual models of plate tectonics that some geoscience undergraduates may be carrying into the workforce or graduate school. During interviews, nearly one-half of upper-class geoscience majors and beginning graduate students represented mountains formed at a continent– continent convergent boundary either as cones sitting on a flat surface or as two sheets of hard rubber that had been pushed together. Sibley’s (2005) findings indicate that some geoscience students do not understand the isostatic compensation provided by a low-density root underneath mountains

    The short of all this is that the belief in continental drift is far from being clear. This indeterminacy is critical for our 99-97 debate: the belief Lowell finds unanimous in the geological lichurchur may not have the same granularity as the AGW endorsement as defined in C13. The difference is even more obvious when transposing the two cases into fact-speak: the fact that continents drift ain’t the same kind of fact than “human activity is very likely causing most of the current GW.” While there is little room to dispute the former, there is room to dispute the latter, if only implicitly. Which means interpreting non-rejection as explicit endorsement looks dubious, at least to me.

    This is more than a nit. A nit would be to say that Lowell’s claims that “the only reliable source is the peer-reviewed literature” and that “until the 1960s, a tiny percentage of scientists believed that continents drifted” aren’t quite compatible, considering the state of peer review before 1960.

  70. John Hartz says:

    ATTP: The issues raised in the following would make for an interesting OP and would generate a lively discussion thread…

    Scientists and policymakers use measurements like global warming potential to compare how varying greenhouse gases, like carbon dioxide and methane, contribute to climate change.

    Yet, despite its widespread use, global warming potential fails to provide an accurate look at how greenhouse gases affect the environment in the short and long-term, according to a team of researchers from Princeton University, the Environmental Defense Fund and Harvard University.

    The researchers argue in the May 5 issue of Science that because global warming potential calculates the warming effects of greenhouse gases over 100 years, they discount the effects of any greenhouse gas that disappears from the atmosphere after a decade or two. This masks the trade-offs between short- and long-term policies at the heart of today’s political and ethical debates.

    What is needed, the researchers conclude, is a standardized approach that recognizes both commonly utilized timescales—20 and 100 years—as a ubiquitous pair. This two-valued approach would provide clarity to climate change policy analyses, which often result in misleading debates about policy trade-offs.

    Current climate change measurements mask trade-offs necessary for policy debates, Phys.org, May 4, 2017

  71. John Hartz says:

    Magma & Willard: You may want to check out…

    Consensus on plate tectonics and climate science by Andy Skuce, Critical Angle, Nov 6, 2015

  72. Magma says:

    Look at the first and third comments, JH. 🙂

  73. Magma says:

    Rounding off this tangent, there’s a recent academic biography of Wegener (Mott T. Greene, 2015) which covers his life and work in 600 well-written but dense pages and is probably the comprehensive work. The combination of that with the magisterial five-volume, 3000-page work The Continental Drift Controversy (Henry R. Frankel, 2014) should cover most of what needs to be known about those subjects by pretty much everyone.

    (Yes, I have all of them and no, I have not read them cover to cover.)

  74. Andy Skuce says:

    The mechanisms for the driving of the plates is still not fully resolved. What clinched the consensus on plate tectonics was the kinematics. This includes: the relative displacements of the plates; the reconstructed fit of passive continental margins; the history of movements revealed by palaeomagnetism; dating of the oceanic crust; and the nature of the three types of plate boundary. The kinematic evidence was so persuasive and coherent that an important test of of the theory—direct measurement by surveying of modern plate movements—was seen as an unremarkable formality. In fact, I can’t even find the reference to that work, if anyone can point me to it, I’d be grateful. (It was done in Greenland, IIRC, and published, I think, in Science.)

    Similarly, Darwin’s theory of evolution by natural selection was persuasive before Mendel and long before Crick and Watson explained the necessary genetic mechanisms.

  75. Magma says:

    @ Andy

    Le Pichon was the first to calculate a globally consistent set of large plate movements on a spherical Earth, with reasonable results of 1 to 5 cm/year relative plate velocities constrained by seafloor spreading rates.
    Xavier Le Pichon (1968) Sea-Floor Spreading and Continental Drift, JGR, 73, 3661-3697

    Proverbio and Quesada used Le Pichon’s work along with very accurate latitudinal variations from five carefully-selected International Latitude Stations from 1900 to 1969 to derive Eurasian-North American relative spreading rate of 4.2 ± 0.9 cm/yr (the terminology, understandably, is obsolete and a bit foreign now, and their estimate is about double the correct value). This reference seems to have been overlooked and quickly forgotten (but as mentioned, Frankel’s history is exhaustively complete).
    E. Proverbio and V. Quesada (1972) Analysis of Secular Polar Motion and Continental Drift, Journées Luxembourgeoises de Géodynamique, 1972, p.281-291

    There was a burst of papers in the mid-1980s as the result of the then-new technique of VLBI and well as satellite laser-ranging geodesy using the LAGEOS satellite (still operational today!). A good review of the state of the field at the time is by Stein.
    Ross S. Stein (1987), Contemporary Plate Motion and Crustal Deformation, Reviews of Geophysics, 25, 855-863.

    So surprisingly enough modern quantitative plate tectonics and climate science are near-contemporaries. I hadn’t realized that it took nearly twenty years to go from geologically-derived plate velocities to geodesically-derived ones.

    Let me know if you’d like copies of any of these.

  76. Andy Skuce says:

    Thanks, Magma. I’ll have a look at those references.

  77. Keith McClary says:

    Did 58 Scientific Papers Published in 2017 Say Global Warming is a Myth?
    http://www.snopes.com/scientific-papers-global-warming-myth/
    “We rank the claims made by both Breitbart and No Tricks Zone as false, because they dramatically misrepresent the findings of the scientists who conducted the research and utilize poorly articulated straw man arguments to further misrepresent the significance of the work of those scientists. These studies were local in nature, narrow in scope, meant to address how the climate system functioned in the past, and pose no threat to the tenets of anthropogenic climate change.”

  78. Magma says:

    Ken and many other readers of this site are already aware of this, but for those who didn’t get the sad news, Andy Skuce died last week following a lengthy illness.

    Exit, Pursued by a Crab

  79. Pingback: 2017: A year in review | …and Then There's Physics

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