The Linear Model of Science in Climate Policy

May 24th, 2005

Posted by: admin

Over at they have an interesting series of articles on climate change. Jon Miller has an article published yesterday titled “Selling Climate Change” that contains some smart advice (do read the whole thing). Here we focus on his first suggestion; one that Prometheus readers know will find a lot of sympathy here: “Don’t debate the science.” He continues,

“Everybody knows that greens love getting into a good debate. It’s not surprising – there’s a powerful scientific, moral and commonsense case to be made for taking action. Unfortunately, those with a vested interest in doing nothing are too shrewd. In the United States especially, they have successfully entangled environmental change campaigners in detailed debates about the validity of the science. It’s a simple strategy: the likes of Exxon throw money at some financially compliant scientists, who produce a report with the appearance of credibility and objectivity. The greens, of course, leap to an enthusiastic defense of their case – and the trap is sprung: the public tunes out (too boring), the media downgrade the story (too complex) and the politicians have the greatest excuse for doing nothing (let’s wait until the science is clear). It’s entirely right to set out the case, of course – but the time has come to have confidence in the scientific consensus around climate change, and to stop debating the science. We urgently need to move the conversation from “is it really happening?” to “what do we do about it?”"

Miller’s call, like our own, to stop debating science is contrary to how many scientists describe their role in the political process. For example, a group of scientists writing last week in the openDemocracy forum make the claim that wise policy making requires accurate scientific judgments:

“In order to choose policy options wisely, decision-makers require the most accurate assessment of the relevant scientific information without having followed every discussion in the technical literature. To that end, scientists have a public role in placing new results in context, distilling the current state of knowledge, and pointing out where continuing uncertainties and problems lie.”

This is an excellent example of an invocation of the “linear model” of science and decision making which I discussed in a recent paper (PDF). The linear model is “based on first getting the science “right” as a necessary, if not sufficient, basis for decision making… “. The linear model places science at the center of political debates:

“If the linear model is indeed an accurate reflection of how the world works then battles over science and how people interpret the significance of science are necessarily of critical importance because certain political outcomes can be made more or less likely through shaping public or policy maker perspectives on the science that putatively supports one agenda or another. However, the linear model has long been understood to be an inaccurate characterization of and even an undesirable approach to the relation of science and decision making because of the ample evidence showing that policy does not simply emerge from scientific understandings (see Oreskes, 2004 in this volume; Sarewitz, 2004 in this volume; Jasanoff, 1987; Wynne, 1991). Consequently, when scientists reinforce the linear model it has potential to create pathologies in decision making. From the perspective of the linear model science not only plays a (if not the) central role in political battle; but because scientific understandings are supposed to motivate political action, winning a scientific debate leads to a privileged position in political battle. Consequently, scientific debates are in effect political debates because resolving scientific debates will resolve political conflicts. Science thus becomes a convenient and necessary means for removing certain options from a debate without explicitly dealing with disputes over values. But because the linear model in fact fails to accurately describe the relationship between science and political outcomes, it may simply mask normative disputes in the language of science, to the possible detriment of both science and policy.”

After the scientists writing on openDemocracy assert that wise policy requires accurate scientific assessments, they then assert exactly the opposite, “We comment here on scientific content in the submission by Benny Peiser in openDemocracy’s climate change debate. Any criticism of his scientific points is however independent of our opinions concerning his preferred policy options.” This raises some obvious confusion: If wise decision making requires accurate assessments, and Benny Peiser’s assessment of science is inaccurate, then surely it stands to reason that the policies that he would recommend (whatever they are) based on science are then unwise policies. If the scientists’ critique of Peiser’s assessment of science is “independent” of judgments of policy, then wise decision making does not depend upon science. It can’t be both ways — judgments about policy cannot simultaneously both “require” and be “independent” of scientific debates.

One reason why scientists invoke the linear model is that it provides plausible deniability for scientists. It allows them to act is an overt political manner while simultaneously claiming to be disengaged from politics. Scholars who study science in society have long seen through this faade, but most scientists remain either unaware of or unburdened by it or its implications.

Miller’s (and our own) call to move beyond debating the science of climate change and onto explicit discussion of policy would certainly be facilitated if leading climate scientists, who for many good reasons are the authoritative voices in the climate debate, themselves decide that wise policy does not depend upon debating the science, and, as Miller recommends, stop debating the science. But ironically enough my own call for scientists to recognize and act on the consensus of knowledge of scholarship in science and society is probably just another hopeless invocation of the linear model. Perhaps instead of invoking the scientific consensus of science scholars as the basis for action, climate scientists could instead benefit from open discussion of a range of choices for how they engage with society.

10 Responses to “The Linear Model of Science in Climate Policy”

  1. Eli Rabett Says:

    I think the idea of a linear model for climate change/greenhouse forcing policy is wrong, much as was the case for the ozone/CFC policy. Rather think of a threshold function, when the science gets some ways above that threshold then the argument shifts rapidly in the direction of remediation and the argument shifts to what should be done. In fact that is what has happened the world over EXCEPT for the US, but even here, the issue is acting as if a threshold has not quite yet been reached, I would argue because of a concerted campaign of blocking propaganda. The arguments used against setting a policy based on the science are all that a threshold has not been reached.

    The science itself accumulates in a linear manner, but the shift in the policy debate is a sudden one. If you are looking for an analogy thing of a see-saw, with the evidence moving up the plank at a steady rate until it reaches the fulcrum and then the board goes over in a rush. Good examples of this are the rather sudden (as such things go) issuance of policy statements on global climate change by AGU, APS, Royal Society, etc.

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  3. Roger Pielke Jr. Says:

    Eli- Thanks for your comemnt. Using your metaphor (which comes close to restating the linear model!;-), in the case of ozone depletion the “threshold” was so exceedingly low (see the Pielke/Betsill paper), as to have little meaning (e.g., in the early 1980s scientific certainty decreased, yet policy development proceeded). In the case of climate change there ae various reinforcing dunamics that keep the attention on science. Given these dynamics I’d suggest that there is no threshold at which action will be compelled. The lessons of ozone (and Europe on climate change) are that science alone does not provide a sufficient basis for action.

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  5. Dano Says:

    Good post.

    I agree with Eli and Roger except that I don’t think science progresses in a linear manner – just like ecosystems that flip, science often accumulates and then tips (using your metaphor) – hence the term ‘breakthrough’.

    And science alone almost never provides a sufficient basis for action, as most policy-makers are not scientists and use other means to inform their decision-making; as soon as scientists learn to harness this basic fact, their findings will become more useful to the public.


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  7. Kooiti Masuda Says:

    We scientists cannot stop debating science publicly.
    It is not because we believe in the “linear” model of policymaking.
    It is just because debating science is our ethos, our way of life.
    Especially when some scientific knowledge is being used in policymaking,
    and when we consider that the particular piece of knowledge is wrong,
    we are obliged to make full efforts to replace it with the right one,
    regardless of whether our interference actually helps or disturbs the
    process of policymaking. We simply cannot admit wrong knowledge prevail.
    (Since any scientific knowledge cannot be absolutely certain, the terms
    “right” and “wrong” here are emphatic. More accurate expressions
    would be “significantly more credible” and “significantly less credible.”)
    If you force us not to debate science, we feel incensed, and we will
    not want to cooperate with you. That is probably not what you want.

    When you think our behavior is irrational in the particular context,
    you should proceed bypassing us rather than forcefully stopping us.
    Then we will feel disappointed, but not incensed.

    Better, you should recruit some of us and educate them to
    behave as policymakers rather than as scientists.
    Most of us feel it risky to abandon scientist-like behavior.
    It means dropping out of our career path.
    Therefore, you should first persuade us that being a policymaker
    can make better chance of job than being a scientist.

    … This is certainly a caricature, but I think that
    it represents something like the ideal type of our behavior.

    Kooiti Masuda

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  9. Gavin Says:

    As the author of the comments in question, I should probably say a few words. Firstly, I don’t really understand what ‘linear’ refers to in this context – it sounds like it is being used a synonym for simple (or even simple-minded), but regardless of what this idea of science policy is called, it is not a terrible idea. Certainly the sentence we used (quoted above) neither implies a constraint on policy options, nor does it imply that the science must be ‘right’ before any options can be considered.

    We did not state that ‘accurate scientific judgements’ are required for policymaking. We said that scientists have a role in assessing the relevant science because the policy makers have neither the time, talent nor inclination to do so. Why is that controversial?

    In this particular case, Dr. Peiser used two irrelevant scientific issues to argue against Sir David King. Who will point out that they are irrelevant except for the scientists who understand the field? Had he asked me (which of course he didn’t), I would have suggested another line of attack for his debating position.

    As is absolutely clear in the climate change debate, these arguments were just surrogates for his real reasons for disputing Sir David’s position. Therefore our response has no implication for the validity of his point of view, because the points we contested are not the basis for that point of view. Some one can use a logical point to argue for a illogical conclusion, and similarly, an illogical point can be used to argue for a logical conclusion. Thus in pointing out an argument is irrelevant to the discussion at hand, one is criticising the debator, not the point being debated. People can of course come to their own conclusion as to why Peiser used such specious arguments instead of something more relevant.

    But… we’ve had this conversation before. If we criticise bad science that is being used to advocate for a particular policy, you have assumed that this means we disagree with the policy. And yet we have also criticised the ‘other’ side when they get the science wrong. Does this mean we are just hopelessly confused about what policy we want? No. It just means we are trying to have the science properly understood – with all of it’s caveats and uncertainties. It cannot be a bad thing to want to educate people.

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  11. Roger Pielke, Jr. Says:

    Dear Kooiti-

    Thanks very much for a very cogent post. I agree with you that the scientific ethos embraces debating science. And this is a fine pattern of behavior within scientific societies, universities, government labs and on the pages of peer reviewed journals — in other words when science is an end goal. But I do think that circumstances are very different when science is viewed as a means (by policy makers, not scientists) to another end. There are many examples of scientific institutions (NAS, IPCC, WHO, President’s Council on Bioethics, German Enquette comissions, OTA etc.) that agree to bring science to the public and policy makers for purposes of informing decisions. In such contexts scientists ought to become aware of their role in the policy process and act in ways that improve not denigrate that process. It is the logic and axiology of the “linear model” that allow scientists simultaneously to treat science as both an end and a means (i.e., scientists can work of getting the science “right” and under the linear model, this is what decision makers need!). But what if the linear model is incorrect or normatively undersirable? Thanks!

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  13. Roger Pielke, Jr. Says:

    Reply #1

    Hi Gavin- I am breaking my response into two parts, first on the concept of the “linear model.” This is a term of art, jargon (sorry) from the community of scholars who study the role of science in society. In its most basic form it looks like this: basic –> applied –> development –> applications –> benefits. It has been a subject of research for more than 40 years. And many scholars have concluded that it is not such a good idea (in spite of its simplicity, many successes over time and endorsement by most scientists). The linear model and its pathologies are well described in a book by Donald Stokes called “Pasteur’s Quadrant” published in 1998. You can read another short critique of it here:

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  15. Roger Pielke, Jr. Says:

    Reply #2


    First, thats again for your thoughtful replies. We do appreciate your willingness to engage on thses issues of science policy. You write, “If we criticise bad science that is being used to advocate for a particular policy, you have assumed that this means we disagree with the policy.” No. Whether you personally agree or disagree with the policy is not the point. The point is that regardless of your motivations or underlying values you ARE playing a political role. It is a visible and significant political role. You can claim to be fencing off of the science, but King, Peiser and the Real Climate authors on (to just take one example) are engaged in a political debate, not a scientific debate. This point is as fundamental to my field as the notion of radiative forcing is to your field. When you write the following, “In order to choose policy options wisely, decision-makers require the most accurate assessment of the relevant scientific information without having followed every discussion in the technical literature” — this sounds to me a bit like the following might sound to you — “In order to model the climate, scientists require that their models be tuned in order for energy fluxes between oceans and atmospheres to be in sync.” You might reply, “Well in some cases this is true, particularly in the past when models were simpler, but the reality is that the practice of developing models is much more complex than this simple statement would suggest.” You might cite papers and actual models to show that my point is incorrect. If I refused to accept the scientific evidence that you presented, you might even call me a “skeptic” out of frustration that the right information does not appear to change my views. If this analogy makes any sense at all, then you might be able to understand where I am coming from. Policy makers do NOT necessarily require scientific assessments to choose policy options wisely (and climate change is a great example). In fact, for many policy issues decision making is facilitated when science is either in the background or a lesser consideration. This is the story of policy responses to ozone depletion. Science did put the issue on the agenda, but science did not compel a response. Now that the ozone regime is mature accurate scientific assessments are of critical importance. But the decision context is a critical variable in understanding when scientific assessments are an asset or a hindrance. I frequently hear from scientists that more, accurate knowledge can never be a bad thing, and I understand (as Kooiti wrote) that the pursuit of turth is part of the ethos of science. But the reality is that in certain political settings efforts to get the science “right” can sometimes (not always, depends on context) make the challenge of policy making more difficult. And for improtant issues, like climate change, such challeneges can lead to stalemate and gridlock. Dan Sarewitz has an excellent paper on this titled, “How Science Makes Environmental Controversies Worse” that I would strongly recommend to anyone interested in this issue:

    One way to deal with this reality that I have suggested if not for scientists to withdraw from a public role, but instead to openly engage on issues of policy, rather than seeking to discuss “only science.” From my perspective, assertions by scientists (again, however sincere or well intentioned) that they are sticking only to science, probably sound to my ears a lot like the scientifically incorrect statements of “skeptics” that you have expressed frustration about. We are both learning that edcuating people on science (whether climate science or policy science) can be a tough go, but we both also agree that it is a effort worth making. Thanks!!

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  17. Gavin Says:

    Roger, I am of course aware that policy makers undertake policies for myriad reasons and that even in nominally scientific issues, science is not often (if ever) the most important consideration. Neither do I dispute the need for “Science .. not to promise a policy solution arising from basic research”. So to that extent I am already converted to the ‘new’ model of science/policy interaction.

    However, I am a scientist. I am not an economist, policy wonk, or grassroots activist. The little credibility I have on these issues is only related to my pronouncements on science, not to anything I have to say about various policy options. My opinion on whether ‘cap and trade’ or ‘regulation’ is more efficient at providing emissions reduction at the least cost, is not as informed as my opinion about whether increased emissions are likely to have a significant effect on climate.

    I (or more generally us scientists) have ended up with a greater political role than usual because of efforts to ’scientize’ the policy debate, as you have frequently noted. We have two choices – either we ignore the bad science that gets thrown around or we get involved and try and educate the people listening. To ignore it is to leave the field open to those who would confuse rather than enlighten and leaves the general populace suspicious of science and scientists, which in the long run imperils the whole scientific enterprise.

    To get involved implies combatting distorted scientific ideas in the political arena, admittedly at the risk of seeming to use science to foster policy agendas. Other scientists will come to other decisions, but personally, I have decided that stepping forward and engaging is a good use of my time. The way I avoid being tarred as an activist is to ’stick to the science’. There is no middle ground here: If I discuss a policy option I am an advocate, if I don’t then I am ‘not engaging the issues’. The only way to be neutral on policy options (for me) is not bring them up. Where in my last piece on the potential for ocean circulation change should I have discussed the post-Kyoto negotiations? Posing the question just underlines the fact that the science is independent of any policy options society decides to pursue.

    However, the ’scientific community’ is not a monolith, and decisions that I make have no noticeable affect on anyone else. They are free to engage in the policy debate if they wish, however, I choose to use my limited time to talk about things I know something about. I find it surprising that I continue to have to defend that position.

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  19. Roger Pielke, Jr. Says:

    Hi Gavin-

    Thanks, lets make this about “climate scietists” rather than just you (because my point is much broader). I certainly can respect any individual’s decision to engage in policy research or not. But a problem exists when the leading organizations of the community decide to focus narrowly on “science.” For example, the IPCC, the leading authority on climate change, maintains that it is “policy neutral” and “relevant, but not prescriptive.” In practice this means that the IPCC does not explicitly discuss a range of policy options. The US National Academy of Sciences most recent report on climate policy was published more than a decade ago. And one of the (if not the) leading voices on the internet on climate (Real Climate) also formally eschews discussion of policy. As I’ve written about here and elsewhere, the fact that leaders of the scientific community have chosen this path (for wahtever reasons) means that each of these institutions has come to be (in both reality and perception) increasingly part of a political battle that takes place through science. this is bad for both science and policy (though it is great if you enjoy pure politics). The collected actions of scientific leaders are actually limiting the role of science as a resource for policy, by facilitating the use of science as a tool of marketing in political battle (e.g., the Hockey Stick debate is a great example of this).

    It is important to observe that the IPCC did in ts FAR have a mandate (in WG III) to discuss policy options. It no longer does. If the scientists who know the most about climate are not discussing with other experts (e.g., economists, technologists, sociologists, philosophers, etc. etc.) what options we have on climate change, then it is fair to ask: Where will we get new, innovative, authoritative, legitimate and salient options for post-Kyoto climate policy? Right now it seems like the answer is “no where”. If so then we can plan on replaying over and over the same old skeptics vs. mainstream debates on climate science.

    Two final points. First, you suggest that scientists have two choices, to ignore misuse of science ot to educate. I’d suggest that scientists have a considerably broader set of options — which I described in an earlier post in terms of an analogy (where to eat?) as Lonely Planet, Kiosk Brochure or Food Pyramid:

    Finally, I recognize that there are many incentives and reasons for scientists to want to focus narrowly on science. (Heck, I enjoy it also!) But in today’s world science has come to be increasingly looked to as a resource for dealing with difficult policy challenges, like cliamte change. Society invests considerable resources in science to facilitate effective actions. In this context I think that it is fair to expect that scientific leadership requires a greater engagement with policy and all of the messy, interdisciplinary, applied realities that go along with it. We made this argument was made is a short essay in 2003, “Wanted: Scientific Leadershp on Climate”:

    Again, I appreciate your enagagement and respect what you guys are up to. And just like you expressed, I can either choose to ignore the politicization of science or try to edcuate those leaders in the scientific communtity about the consequences of their actions, at least as viewed from the perspectives of some who study thr role of science in policy and politics.