Monday, 24 November 2014

Casual consensus and a lot of science

Have not been blogging much lately and the number of readers is suffering. So I need another post on the Climate Consensus; always a runner. At the Guardian, there is a discussion going on between 3 interesting people. John Cook, the benevolent dictator of Skeptical Science, Peter Thorne, the benevolent dictator of the International Surface Temperature Initiative (ISTI) and the benevolent dictator of And Then There's Physics (ATTP).

What I took from the discussion is that maybe we should not focus too much on communicating the consensus, still communicate it, but casually. That may actually make the consensus point more clearly.

If you do so casually, you produce less an impression that this could be a topic of debate, you thus create less false balance. If you mention the consensus casually, but focus on interesting points of scientific disagreement you also do not give the impression that the consensus means that everything is understood in sufficient detail.

AndThenTheresPhysics paints the dilemma:
"My understanding of the situation is something like this, though. A reasonably vocal group of people argue that there is a great deal of disagreement about climate science and that there is no consensus. Some other people then do a study to show that there is indeed a consensus, at least with regards to the basics. The first group of people then do their utmost to attack that result. Consequently another group of people do another study to show, once again, that there is a consensus. That too is then attacked so as to undermine that there is indeed a consensus. Then another study takes place, until we get to the point that even scientists are starting to question the whole consensus messaging because they perceive it as an attempt to communicate climate science through consensus messaging only (which I don't think is the intent, even if it might seem that way). That scientists are now criticising this then gives those who would rather there was no consensus (or that people thought there was no consensus) more ammunition to attack the various consensus projects."
Peter Thorne replies:
"But how do you break catch-22 here? Its not clear that continuing round the circle achieves anything other than getting dizzy. There are many interesting scientists on blogs and twitter (yourself and skepticalscience included) communicating in varied ways with nuanced messaging that perhaps gives a better sense of the science and the process than repeated articles on a consensus at the Guardian ever could."
"My point would be that while it is important to communicate the consensus it is at the same time a significant mistake in my personal view to obsess upon it or make it even the central strand of any discussion upon the issue."
Clearly we should avoid given the wrong impression that there is no consensus on the basics, but maybe just a half sentence with a link is enough on the internet and the rest of the message can focus on science. In the mass media, which is what Cook is thinking of, a simple message focussed on the existence of a consensus on climate change among climate scientists may well be effective. I am no expert, but Cook's arguments sound convincing.

Even if one accepts that consensus messaging is most effective to convince the population that there is a problem, that still does not mean that scientists should do this. Scientists have their own aims, skills and interests.

Peter Thorne:
Carbon dioxide and gases active in the IR spectrum we have known for over a Century will act to warm the atmosphere. On that you will find as close to consensus amongst qualified experts as in any field.

But that understanding is far from the end of the story and as you get to more and more nuanced questions there is no longer the degree of unanimity or consensus. If we knew everything there is to know then you wouldn't see several thousand papers a year appear in the peer reviewed literature on the subject providing new insights and building the knowledge base. Nor would you see repeated assessment activities such as IPCC. The issue with saying there is consensus repeatedly is that people then think, mistakenly, that all aspects of the science are settled. This is very far from the case.
As scientists we are naturally also very aware of the problems that are not solved. That is what we work on every day. That is the fascinating part. Just because the main lines are solid does not mean that we should no longer expect important changes in our understanding of the climate system and that all we need are applied studies on the impacts of climate change.

It seems to me somewhat premature to invest much manpower into studying how cauliflower, leek or wine with grow within some small region of Germany, France or Luxembourg. Not only because that needs predictions at a very local scale, which are much more difficult than large-scale predictions, but also because there is still important work to do the fundamentals of climate science. I would personally mention the influence of non-climatic changes on trends in extreme weather and I would love to see a global station network making climate-quality measurements, designed to avoid introducing non-climatic changes.

Not that I would argue that we should not do any impact studies. Doing so gives a first view of where the main societal problems may lie, it helps us see where the difficulties of impact studies are and to develop the tools that are needed to make reliable impact studies and estimate the corresponding uncertainties. However, maybe we do not need to study every vegetable for every province at his stage.

The International Surface Temperature is building an open global temperature dataset with good provenance relying on volunteers and some support by NOAA. For the first time on a global scale the ISTI will validate the algorithms to remove non-climatic temperature changes. Generating the validation dataset is supported by the MetOffice, but mainly performed by volunteers. My own smaller-scale validation study was a volunteer project, with some travel funding by COST. Peter is co-chair of GRUAN, a network of climate-quality radiosondes. A rather sparse network. And governments around the world are pruning the station network, regularly destroying some of the longest series we have. I am surely bias, but I would put my priorities in the data the science is founded on and not with cauliflower.

Yes, it is warming, but how much, where and when. If that changes due to our better understanding, we can redo all the studies for every vegetable and province. And that is just temperature. Many more aspects of the climate are changing. And those are just examples from my field. Other climate scientists could likely make a similar list of important questions that still need to be resolved. Especially, when it comes to adaptation local skill is important and hard to get. Investing in basic science may well save a lot of money for unnecessary adaptation measures.

Perhaps Peter Thorne said it better than I have:
"If we want to make truly informed and effective adaptation and mitigation decisions it is incredibly dangerous to contend that there is a consensus on anything more than the most general abstract aspects such as that Carbon Dioxide emissions are causing warming."

Citizen and scientist

When a mitigation sceptics doubt something basic, I find it natural for a normal citizen to answer, well there is a clear consensus on this topic, that is enough for me to hold this view, convince the scientists first before bothering me as a non-expert. That is just a shorthand for: I do not want to discuss this with you, I expect this to be pure nonsense and we are not the right persons to discuss this.

I would prefer it if a scientist (in the right field) would answer by providing the evidence. This is our role in society, even if it is not the most effective strategy to convince the population there is a problem.

The answer is mainly to make clear to the casual reader that there is an answer; one should have no illusions that this will lead to a productive conversation with the mitigation sceptic. If the answer is too good, the mitigation sceptic will change the topic and try the same loop somewhere else.

Even as scientist you do not have to jump all hoops. If someone claims CO2 is not a greenhouse gas, or that the temperature is decreasing or we will soon enter an ice age, there is nothing wrong with asking such fools to first convince their political allies Anthony Watts, Jo Nova or Roy Spencer, who officially reject these claims.

Depending on your role, you communicate differently. Thus maybe the Guardian debate was partially about how people see as their role.

As a citizen I feel that the arguments of John Cook make a lot of sense and I guess that it is necessary and effective to communicate to the publication that there is a consensus within climate science about the basics and that we are performing a dangerous experiment with the climate system our livelihoods depends up on.

In my role as scientist further aspects become important and one should make sure that the consensus message does not give the wrong impression that we already know everything sufficiently accurately and that all we need are impact studies for cauliflower.

Related reading

Why we need to talk about the scientific consensus on climate change. The Guardian article that inspired this post.

Five reasons scientists do not like the consensus on climate change. My first try to explain why scientists may not like communicating consensus and why these arguments do not hold water.

"Blinded by Science: How 'Balanced' Coverage Lets the Scientific Fringe Hijack Reality". A repost of an oldie from 2004 that is still current by Chris Mooney in Columbia Journalism Review.

The BBC will continue fake debates on climate science. "When a new member of our solar system was discovered, there was no debate with an astrologer claiming there was no empirical evidence, because you could not see VP113 with the naked eye."

The value of peer review for science and the press For science peer review is a filter. For the press an anchor.

On consensus and dissent in science - consensus signals credibility You have to pick your fights. On topics where there is dissent there is clearly work to do. Where there is a consensus finding a problem is hard, but thus also most rewarding.

The Tea Party consensus on man-made global warming. The people that call the climate consensus based on scientific evidence "group think", have a very strong consensus themselves, without much scientific evidence. Group think?


  1. Hello there - It was a very interesting conversation between them all. I know that there are also 'non-experts' among us on the Guardian comments who recognize the importance of the consensus as a tool for communication, but equally wish it could be presented in different ways (to avoid people just switching off, or for it to be misconstrued as a debate about the unequivocal scientific facts - the Earth's energy budget is continuing to rise due to CO2 in the atmosphere and at least 50% - if not 100% - is attributable to human activity). So how best to evolve the conversation?

  2. Yes, the best estimate is about 100%. More than 100% of the warming from CO2 and some cooling by aerosols (airborne particles).

    I do have some hope that people can distinguish between the questions whether we are causing global warming, whether there is a consensus and whether one should offensively communicate this.

  3. I suppose my understanding is that, if you want an audience to fully accept a message, they need some understanding of why it exists. I don't mean the consensus paper itself, but why the basic facts are unequivocal. Why there is such strong agreement amongst experts. But provided in bite size, clear pieces. And I guess one problem with being 'offensive' is that it can be misinterpreted as 'defensive'. If the cold hard facts are presented along with the consensus message, perhaps there's less room for misinterpretation. I do think that it has been presented recently in such a way as to appear to be defending itself and this is misleading and distracting.It's presenting an opportunity for argument and turning away from what is, in effect, accepted as certain. Does that make any sense? I may not have explained it well!

  4. Victor,

    "What I took from the discussion is that maybe we should not focus too much on communicating the consensus, still communicate it, but casually. That may actually make the consensus point more clearly."

    I've never once brought it up because the backlash -- in the form of painting it as a fallacious appeal to popularity -- was pretty much immediate. ATTP nails it exactly; communicating the consensus to a contrarian only gives them another avenue to steer the conversation away from the science itself. But here I speak from the perspective of someone who engages in the debate directly, so my goal is to stay on point as much as possible since the other side will typically already be doing everything possible to distract. Mass media communications are different since there the audience will typically contain a much larger cross-section of consumers who may have heard the noisy "disagreement" soundbite but are still receptive to the well-researched rebuttals. At this point I don't think touting the 97% as the headline in media is constructive, but worked into the main body of the communication still seems appropriate.

    From Peter Thorne: "The issue with saying there is consensus repeatedly is that people then think, mistakenly, that all aspects of the science are settled. This is very far from the case."

    Even more damaging was saying any portion of the science was settled -- it's all too easy for that statement to be contorted into "you warmists aren't doing science, you're followers of a religion" argument. I actually find that the more prominent statements of uncertainty and unsettled science I have to draw from the more comfortable I feel on my end of the debate. Since I'll never "win" in the sense of convincing a contrarian -- the actual science already doesn't convince them -- I'm playing not to lose. I may be writing TO the contrarian, but I'm constantly mindful that I'm not writing FOR them. Nothing takes the wind out of a gasbag than agreeing with them unexpectedly: "Exactly right, no non-trivial science is ever settled." One less thing for them to attack me with, and one more false negative stereotype of "non-scientific warmists" disrupted.

  5. mountainrunnermum, I am happy to explain the science as far as I can. Especially when it comes to non-climatic changes in the observational records. However, I do not expect that that would help much. If only because only a small part of the population has the skills and the attention to understand more than an strongly simplified version (that includes me for most topics as well).

    Sou just wrote a long worthwhile post on this. The last paragraphs read:

    The ability of people to hoodwink themselves is quite amazing. I'm not surprised that some scientists don't get it. It's not rational. Physical scientists deal with hard data. And most of them would socialise with people like themselves, who also think and analyse more than "believe". So they probably don't realise that the above comment is "hard data". It's evidence. It shows them to be wrong if they assume that "hard data" is sufficient to persuade people. It's not. Not even when a person knows they are being hoodwinked. Which is almost surreal.

    Scientists have "beliefs" about things outside their field of competence, too

    Let me add one more thought. I've read scientists who argue that letting people know about the scientific consensus (that humans are causing global warming) isn't necessary and might even be counter-productive. Let's hope that this "belief" of theirs, which is constantly being refuted by hard data, by the evidence - will change. Are they as willing to challenge their own beliefs, given the mounting evidence that they are in error on this point? Or is this just another example of humans holding some beliefs so dear that they cannot change them, no matter how much hard evidence is put in front of them? Even heavy duty, evidence-driven scientists are prone to having unshakeable "beliefs", it would seem.

  6. Brandon R. Gates, I think it matters how you bring up the climate consensus. You should not write that something is true because there is a consensus (I admit an extreme formulation). You can write, that for you personally the strong consensus in climate science is enough for you accept that there is a problem. Then you just describe your feelings, these cannot be wrong.

    You might still get some token resistance, they fear the consensus enormously, they realise that for most people it is highly convincing. After having described your feelings once, you can just ignore the infantile response and continue talking about the science.

    And, yes, when talking about the science it is good to stick to one topic and not let the mitigation sceptics jump from topic to topic, always changing before it goes too much into detail and it would become too obvious that he is wrong.

    "Exactly right, no non-trivial science is ever settled" is a very good statement.

    Just as admitting that something you wrote before was inaccurate or wrong. They never admit any errors, at least I cannot recall seeing that, thus doing so makes you look like a very reasonable person, especially in contrast to the political extremists you are debating.

  7. Victor,

    Thanks for your thoughts. I rarely bring up the consensus overtly in any form because then it offers the perfect distraction along the lines of your extreme formulation by way of response. What often do instead is point out that the reason so much is known about how to attack the consensus position is because working climatologists are diligent about point out the uncertainties in the current state of the science, or poor assumptions of the past. If I'm feeling particularly rigorous, I'll post a cite. I can't recall ever being challenged when I frame it that way.

    Do most contrarians fear the consensus? I'd never thought of it in those terms until you wrote it. What I pick up on most (here in the US) is moral outrage against liberal politics. Fear most certainly drives it, but it's something else too I think; jealousy of legitimacy.

    I have seen some admit to being wrong, but only ever to those on their own side. I've had to eat my own words twice recently, one a very minor gaffe -- not really fair that I was charged with it, but I took it anyway -- the other a very serious math error. The latter I caught myself and I then disavowed my entire explanation as too simplistic an approach. Some interesting good faith discussion actually followed from that.

  8. jealousy of legitimacy.

    That could be right, but would be quite weird, wouldn't it? After decades of alienating scientists, scholars and intellectuals from them. By nature scientist are likely spread over the entire political spectrum.

    Political questions are completely unrelated to scientific ones. Scientific questions are specific as to allow only one answer. Political questions are about interests about comparing apples and oranges and political questions are general, no matter how much you talk, you can always disagree.

    Thus you could expect scientists to be of every political colour. In Europe I also have the feeling that this is the case for science in general. For the natural sciences there might be a small left wing bias, but just a small one. Maybe because people from more conservative families prefer to study other stuff, economy, law, medicine.

    It seems to be a specific American issue that it has become hard to be an intellectual and openly conservative. Why do the conservatives have to attack evolution? That is even madder than climate change. And they could be against climate change without claiming that CO2 is life and does not warm the climate or that there is no warming. They could just doubt the impacts, they could just argue that the solutions are worse than the problem. That would be much more credible positions. I do not understand how they got into the trap of becoming the anti-science camp and thus alienate educated people.


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