Climategate And Post-Normal Science

Guest Post by Michael Kile,
It was an important moment in the Climategate saga. Yet few remember Jerome Ravetz’s damning critique of the University of East Anglia’s Climate Research Unit (CRU) posted on
WUWT in early 2010.

Ravetz is an eminent American philosopher of science and an Associate Fellow at Oxford University’s James Martin Institute for Science and Civilisation. (Personal web page here; Oxford pages here and here.) For much of his career he has been challenging claims of scientific objectivity and developing a concept of “post-normal science” (PNS).

We can understand the root cause of Climategate as a case of scientists constrained to attempt to do normal science in a post-normal situation. But climate change had never been a really ‘normal’ science, because the policy implications were always present and strong, even overwhelming.  Indeed, if we look at the definition of ‘post-normal science’, we see how well it fits:  facts uncertain, values in dispute, stakes high, and decisions urgent.  In needing to treat Planet Earth like a textbook exercise, the climate scientists were forced to break the rules of scientific etiquette and ethics, and to play scientific power-politics in a way that inevitably became corrupt.  The combination of non-critical ‘normal science’ with anti-critical ‘evangelical science’ was lethal. (J Ravetz, WUWT, 9 February, 2010)

Some environmentalists had been using Ravetz’s PNS concept to drive a looser – more subjective – approach to decision-making under uncertainty, urging greater use of the so-called “precautionary principle”, a “principle” of pseudoscience, not genuine science.

The late Stephen Schneider (1945-2010), then Stanford University professor for Interdisciplinary Environmental Studies and editor of the journal Climatic Change, was one of them. He was also an IPCC lead author. Schneider advised other lead authors how to deal with uncertainty in a climate context in the IPCC’s Third and Fourth Assessment Reports.

The management of uncertainties is not just an academic issue but an urgent task for climate change policy formulation and action…Various vested interests may inhibit, delay, or distort public debate with the result that “procrastination is as real a policy option as any other, and indeed one that is traditionally favoured in bureaucracies; and inadequate information is the best excuse for delay (Funtowicz and Ravetz, 1990)”. (AR4 WG III section 10.1.5: Robust decision-making)

When The Royal Society published a commemorative volume of essays in 2010, Seeing Further – The Story of Science and The Royal Society, it included one by Schneider: “Confidence, Consensus and the Uncertainty Cops: Tackling Risk Management in Climate Change.” At the time, he was struggling (as the IPCC still is) to deal with what he described as the “significant uncertainties” that “bedevil components of the science”, “plague projections of climate change and its consequences”, and challenge the traditional scientific method of directly testing hypotheses (‘normal’ science). His solution was ambitious: to change ‘the culture of science’ by developing a language that would convey the gravity of the situation “properly” to policy makers.

As climate uncertainty was (and is) so intractable — and incomprehensible to the public — Schneider introduced the rhetoric of risk management – “framing a judgement about acceptable and unacceptable risks” – and pseudo-probability. While he claimed he was “uncomfortable” with this “value judgement” approach – he was even “more uncomfortable ignoring the problems altogether because they don’t fit neatly into our paradigm of ‘objective’ falsifiable research based on already known empirical data.”

Schneider proposed a new subjective paradigm of “surprises’ in global climate scenarios, one with “perhaps extreme outcomes or tipping points which lead to unusually rapid changes of state”; while admitting that, “by definition, very little in climate science is more uncertain than the possibility of ‘surprises’.”

This was a pivotal moment. Schneider had smuggled a contrived “language for risk” into the IPCC; one derived from his personal (and the IPCC’s) “value frame” and that was adopted in subsequent reports. They now had, he wrote triumphantly, “licence to pursue risk assessment of uncertain probability but high consequence possibilities in more depth; but how should we go about it?” How, indeed?

Schneider’s 2010 Royal Society essay concluded: “Despite the large uncertainties in many parts of the climate science and policy assessments to date, uncertainty is no longer a responsible justification for delay.” Yet how can one seriously argue the more uncertain a phenomenon, the greater is the risk to humankind?

Needless to say, it took Schneider a long time to “negotiate” agreement with climate scientists on precise “numbers and words” in the Third Assessment Report cycle. “There were some people who still felt they could not apply a quantitative scale to issues that were too speculative or ‘too subjective’ for real scientists to indulge in ‘speculating on probabilities not directly measured’. One critic said: ‘Assigning confidence by group discussion, even if informed by the available evidence, was like doing seat-of-the-pants statistics over a good beer.’”

Over the next few years – and many beers later – “confidence” in the key IPCC findings came to be expressed in a “calibrated language” all its own, one that can lull a credulous reader into believing a show-of-hands consensus- quantified with bogus precision – is superior to mere opinion. From its latest SR:

Each finding [in this Special Report] is grounded in an evaluation of underlying evidence and agreement. A level of confidence is expressed using five qualifiers: very low, low, medium, high and very high, and typeset in italics, e.g., medium confidence. The following terms have been used to indicate the assessed likelihood of an outcome or a result: virtually certain 99–100% probability, very likely 90–100%, likely 66–100%, about as likely as not 33–66%, unlikely 0–33%, very unlikely 0–10%, exceptionally unlikely 0–1%. Assessed likelihood is typeset in italics, e.g., very likely. This is consistent with AR5 and the other AR6 Special Reports.

Additional terms (extremely likely 95–100%, more likely than not >50–100%, more unlikely than likely 0–<50%, extremely unlikely 0–5%) are used when appropriate. This Report also uses the term ‘likely range’ or ‘very likely range’ to indicate that the assessed likelihood of an outcome lies within the 17-83% or 5-95% probability range. (IPCC SR Ocean and Cryosphere, 24 September, 2019, page 4)

Ravetz was quick to post a response to set the record straight.

I would like to defend myself against a charge that has been made by various critics. This is, that I personally and intentionally laid the foundations for the corrupted science of the CRU, by providing the justification for Steve Schneider’s perversion of scientific integrity. First, there is no record of the guilty scientists ever mentioning, or even being aware, of PNS during the crucial earlier years. Also, shoddy and corrupted science in other fields did not wait for me to come along to justify it. My influence is traced back to a single footnote by Steven Schneider, citing an essay by me in a large, expensive book, Sustainable Development of the Biosphere (ed. W.C. Clarke and R.E. Munn), (Cambridge, University Press, 1986). PNS first came into the climate picture with the quite recent essay by Mike Hulme in 2007. That was a stage in his own evolution from modeller to critic, and came long after the worst excesses at CRU had been committed. I should say that I do not dismiss conspiracy theories out of hand, since some of them are correct! But this one really does seem far-fetched. (J Ravetz, WUWT, 12 April 2010, Debate and post-normal science

According to Ravetz, the relationship between scientists and policy-makers has changed; the technocrat ideal of the nineteenth century is dead. We have entered what he calls a “post-normal” age, where science too has become “post-normal”. It no longer speaks “value-free” truth based on impartiality and objectivity. So-called “consensus” advice cannot be considered the objective truth. How do we prevent the self-interested exploitation of uncertainty in such an age?

For Schneider, and presumably the IPCC, it seems to have been by adding “quantitative modifiers”, or phrasing all conclusions in a way to “avoid nearly indifferent statements based on speculative knowledge.”

“We have to offer up scary scenarios,” he said, “make simplified, dramatic statements, and make little mention of any doubts we might have…Each of us has to decide what the right balance is between being effective and being honest.” For Ravetz, this was PNS in action.

In February, 2010, Ravetz posted “Climategate: Plausibility and the blogosphere in the post-normal age” on WUWT. He later released other essays, most of which were ignored by alarmists and the MSM.

What I say may be shocking to some [readers]. I argue that the ‘global warming’ campaign can be best understood as yet another of the Wars that have characterised politics in recent years….Now the evil empire of choice is Carbon, intended to be vanquished by an infinitely corruptible system of bureaucratically defined payments for non-existent transactions. (J Ravetz, Oxford Magazine, 2010)

Ravetz kindly agreed to elaborate further on Climategate and its possible implications for science. Several extracts from his 9 February 2010 WUWT critique are followed below by his answers to my questions.

How could the illusions persist for so long until their sudden collapse? The scientists were all reputable, they published in leading peer-reviewed journals, and their case was itself highly plausible and worthy in a general way.  Individual criticisms were, for the public and perhaps even for the broader scientific community, kept isolated and hence muffled and lacking in systematic significance.  And who could have imagined that at its core so much of the science was unsound?  The plausibility of the whole exercise was, as it were, bootstrapped.  I myself was alerted to weaknesses in the case by some caveats in Sir David King’s book The Hot Topic; and I had heard of the hockey-stick affair.  But even I was carried along by the bootstrapped plausibility, until the [Climategate] scandal broke. (J Ravetz, WUWT, 9 February, 2010)

MK: Is it accurate to say you were sympathetic to the alarmist case on climate change until Climategate?

JR: Yes, I saw climate change as another sort of evidence of humanity’s disruption of the ecosphere; my reaction was, “why not this too?”  I was aware that the more lurid predictions of the alarmists of the 1960s (population bomb, resource depletion, etc.) had not been realised; but there is quite enough of alarming developments otherwise.

MK: Could you describe in more detail why you now consider so much of climate science “unsound”?

JR: In my latest essay, Climategate: the unravelling and its consequences, I distinguish between Climate Science, which is fully aware of complexity and uncertainty, and the ‘CAGW’ (Carbon-based anthropogenic global warming) science of the small group that fed directly into the IPCC.  That is becoming increasingly exposed as unsound, thanks to the critics on the blogosphere.  The ‘Nature trick’ is the most egregious case, but there are others.  Some now assert that the temperature records have been systematically distorted in order to produce an apparent rise – the simple method was to progressively delete the stations from cooler places.  And now Arctic ice is growing in extent; and it seems that its decrease was more due to patterns of winds than to warming air.

The deeper problem for CAGW science is to show that there has been a sudden significant unprecedented rise in temperatures, over a long enough period to count as ‘climate change’ and not just cyclical variability.  Removing the Medieval Warm Period and Little Ice Age was essential for that programme.  The very varied, uncertain and scattered field data did not really add up.  And the models were exposed in 2000 as giving any prediction you liked, depending on the assumptions and conventions.   The propaganda has always displayed anything warmer as evidence for climate change, and anything cooler as a temporary shift in the weather.  After a while that loses plausibility.

To have a political effect, the extended peers of science have traditionally needed to operate largely by means of activist pressure-groups using the media to create public alarm. In this case, since the global warmers had captured the moral high ground, criticism has remained scattered and ineffective, except on the blogosphere.  The position of Green activists is especially difficult, even tragic; they have been extended peers who were co-opted into the ruling paradigm, which in retrospect can be seen as a decoy or diversion from the real, complex issues of sustainability, as shown by Mike Hulme.  Now they must do some very serious re-thinking about their position and their role.” (J Ravetz, WUWT, February, 2010)

MK: Has there been any reaction from Green activists to your assessment of their position on climate change post-Climategate as “especially difficult, even tragic”?

JR: None!  But I have not been in touch with Green activists for some time.  You may have seen that there was a posting on the Greenpeace website (since taken down) that called for direct action against the enemies of climate change.  I have personal memories of people who had committed themselves to a cause, political or religious, and then found it extremely difficult or quite impossible to admit that they had been badly mistaken.  So – one might say – just as the very varied and complex cause of militant Socialism was appropriated by Stalin, so has the official Green movement been appropriated by Al Gore.  And those who identified with the good cause are then trapped.

MK: Were you surprised by the conclusions of the UK House of Commons Science and Technology Committee Report on Climategate released on 31 March 2010?

JR: Not in the slightest!  What were they supposed to do?  The ruling orthodoxy (as expressed by Lord Robert May) is still CAGW; so how could an official body cast doubt on it?  But many will remember how the talking heads of science and medicine were assuring the public that British beef is safe, even for years after the cat ‘Mad Max’ had come down with Mad Cow disease.  Their problem is that the longer they hold onto the party line, the more they lose credibility with the public.

The examples of shoddy science exposed by the Climategate convey a troubling impression.  From the record, it appears that in this case, criticism and a sense of probity needed to be injected into the system by the extended peer community from the (mainly) external blogosphere.

The total assurance of the mainstream scientists in their own correctness and in the intellectual and moral defects of their critics, is now in retrospect perceived as arrogance.  For their spokespersons to continue to make light of the damage to the scientific case, and to ignore the ethical dimension of Climategate, is to risk public outrage at a perceived unreformed arrogance. (J Ravetz, WUWT, 9 February, 2010)

MK: Do you expect the University of East Anglia’s new Scientific Assessment Panel to conclude, as you have done, that Climategate has exposed troubling examples of “shoddy science”?

JR: I would be astonished.  You may know the dictum of the historian Lord Acton:  power corrupts, and absolute power corrupts absolutely.  My version of that is ‘responsibility corrupts, and responsibility without power corrupts absolutely’.  Those who are required to reassure the public that quite obvious bad things never happen, are trapped most tragically.

To the extent that the improved management of uncertainty and ignorance can remedy the situation, some useful tools are at hand.  In the Netherlands, scholars and scientists have developed Knowledge Quality Assessment methodologies for characterising uncertainty in ways that convey the richness of the phenomenon while still performing well as robust tools of analysis and communication.  Elsewhere, scholars are exploring methods for managing disagreement among scientists, so that such post-normal issues do not need to become so disastrously polarised.

MK: To what extent do you believe your suggested tools for improving management of uncertainty and ignorance could remedy the situation now confronting climate science?

JR: The tools are there, for such a time when the political will is there.  We are now seeing a stirring of critical thinking about the ‘science’ of finance (and more generally economics), and important people are reminding their colleagues that uncertainty and ignorance must be respected.  It is possible (I can say no more) that if the present crisis over Climategate matures to the point of confrontation, then in the aftermath there could be a more sophisticate, respectful and might I say humble approach by leading scientists to the complex problems of our age.

And what about the issue itself?  Are we really experiencing Anthropogenic Carbon-based Global Warming?  If the public loses faith in that claim, then the situation of science in our society will be altered for the worse. There is very unlikely to be a crucial experience that either confirms or refutes the claim; the post-normal situation is just too complex. The consensus is likely to depend on how much trust can still be put in science.  The whole vast edifice of policy commitments for Carbon reduction, with their many policy prescriptions and quite totalitarian moral exhortations, will be at risk of public rejection.  What sort of chaos would then result?  The consequences for science in our civilisation would be extraordinary. (J Ravetz, WUWT, 9 February, 2010)

Michael Kile

14 April 2010


Funtowicz, S O, & Ravetz, J R, 1990, Uncertainty and Quality in Science for Policy. Dordrecht: Kluwer Academic.

Moss, R.H. and Schneider, S.H., 2000: Uncertainties in the IPCC TAR: Recommendations to lead authors for more consistent assessment and reporting. In: Guidance Papers on the Cross Cutting Issues of the Third Assessment Report of the IPCC [eds. R. Pachauri, T. Taniguchi and K.Tanaka], World Meteorological Organization, Geneva, pp 33-51

Ravetz, J R, 2010a, Climategate: The unravelling and its consequences. Oxford Magazine, Eighth Week, Hilary Term.

Ravetz, J R, 2010b, Climategate: Plausibility and the blogosphere in the post-normal age. WUWT, 9 February 2010, Climategate plausibility and the blogosphere in the post-normal age

Ravetz, J R, 2010c, Willis, epidemics, rough-tumble debate and post-normal science. WUWT, 12 April 2010, Debate and post-normal science

Ravetz, J R, 1986,” Usable Knowledge, Usable Ignorance: Incomplete Science with Policy Implications. In Clark and Munn, (eds.), Sustainable Development of the Biosphere, New York, Cambridge University Press, pp 415-432.

United Nations, 2007, Climate Change 2007. Fourth Assessment Report (AR4), Intergovernmental Panel on Climate Change (IPCC),

via Watts Up With That?

November 16, 2019 at 12:32PM

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