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David Henderson: Submission to the InterAcademy Council Review of the IPCC

Submission to the InterAcademy Council Review of the IPCC


I am Chairman of the Academic Advisory Council of the Global Warming Policy Foundation. On 26 May the InterAcademy Council invited the Foundation to submit written comments to the independent Review Committee. At the suggestion of the Director of the Foundation, Dr Benny Peiser, I am submitting herewith my own comments. While this submission is personal, it has been endorsed by the GWPF.

I am an economist, not a climate scientist. I became involved with climate change issues, by accident not design, towards the end of 2002. Up to that time, I had formed no considered views on the subject, and had seen no reason to question the work and role of the IPCC. I was an uninvolved spectator.

To begin with, my main involvement was limited to some economic and statistical aspects of this huge and complex array of topics. Over time, however, my interests and concerns have broadened in ways that I had neither planned nor anticipated. Increasingly, and unexpectedly, I have become critical of the way in which issues of climate change have been viewed and treated by governments across the world.

In particular, I have become a critic of the official expert advisory process which governments have created and continue to rely on, within which the main single element is the work of the IPCC as reflected in its successive Assessment Reports. Over the past 22 years governments everywhere, and a great many outside observers too, have put their trust in the expert advisory process as a whole and the IPCC process in particular. I have come to believe that this widespread trust is unwarranted

In the remainder of this note I first summarise my reasons for holding this view (‘diagnosis’) and then sketch out some broad suggestions for improvement (‘prescription’). In the interests of brevity, I have not directly responded to the list of ten questions that the Inter-Academy Council has drawn up. In answer to the first question, however, I have played no part in any of the IPCC assessments.


In the ‘principles governing IPCC work’, laid down by the Panel’s member governments, the IPCC is required to conduct its assessments on ‘a comprehensive, objective, open and transparent basis’. This requirement has not been met. The process of preparation of the Assessment Reports is far from being a model of rigour, inclusiveness and impartiality. It has shown itself to be professionally flawed.

The main headings of unprofessional conduct, none of which I would have noticed or suspected had I not become seriously involved, have been as follows:

• Over-reliance on in-group peer review procedures which do not serve as a guarantee of quality and do not ensure due disclosure;

• Serious and continuing failures of archiving and disclosure in relation to peer-reviewed studies which the IPCC and member governments have drawn on;

• Continuing resistance to disclosure of basic information which reputable journals increasingly insist on as a precondition for acceptance of papers;

• Basic errors in the handling of data, through failure to consult or involve trained statisticians;

• Failure to take due account of relevant published work which documented the above lapses, while disregarding IPCC criteria for inclusion in the assessment process;

• Failure to take due note of comments from dissenting critics who took part in the preparation of the Panel’s Fourth Assessment Report (AR4);

• Resisting the disclosure of professional exchanges within the AR4 drafting process, despite the instruction of member governments that IPCC proceedings should be ‘open and transparent’; and last but far from least

• Failure on the part of the IPCC and its directing circle to acknowledge the above deficiencies, still less to remedy them.

Comprehensive exposure of these flaws has come from a number of independent commentators: in particular, in relation to key chapters of the highly influential AR4 report from the IPCC’s Working Group I, the work of Stephen McIntyre, Ross McKitrick and David Holland has been outstanding, while the (2006) report of the Wegman inquiry is a key document.

In this context, I would particularly commend to the Review Committee two papers: David Holland’s ‘Bias and Concealment in the IPCC Process’ (Energy and Environment, Vol. 18, No. 7+8, 2007), and Ross McKitrick’s chapter in The Global Warming Debate, a book published in 2008 by the American Institute for Economic Research. Both papers, with full supporting evidence, put in question, first, the claims to authority of arguments which have been at the core of the IPCC’s treatment of the scientific evidence, and second, the objectivity and neutrality of leading IPCC authors and reviewers.

These two documents predate (1) the mass release of emails from the Climatic Research Unit of the University of East Anglia (’Climategate’), and (2) the evidence that has emerged concerning sources and treatment of evidence in the AR4 report from the IPCC’s Working Group II (‘Glaciergate’). Under both headings, and especially the former, what has now come to light powerfully reinforces the case made by critics of the IPCC process. Both developments are taken into account in the important paper which David Holland has just submitted as evidence to the Review Committee.

As noted, the defects in the IPCC process, and the official expert advisory process more broadly, have gone unacknowledged and unremedied by what I call the environmental policy milieu, and the critics have been largely disregarded. This high-level official failure, as also the defects themselves, are easily accounted for: both have resulted from chronic and pervasive bias. Right from the start, members of the milieu, as of the IPCC’s directing circle, have been characterised by what has been well termed ‘pre-commitment to the urgency of the climate cause’. Today as in the past, the senior officials involved, in national governments and international agencies, are committed persons; and were this not the case, and known to be the case, they would not be where they are. They and their predecessors would not have sought their respective posts, nor would they have been seen by UN agencies and member governments as eligible to hold them, had they not been identified as holding that human activities are putting the planet at risk. The official advisory process is run today, as it has been from the start, by true believers.

To repeat: it is not just the IPCC process that is in question here. The basic problem of unwarranted trust goes further: it extends to the chronically biased treatment of climate change issues by responsible departments and agencies which the Panel reports to, and in nationally-based organisations which they finance.

It is not just the environmental policy milieu that is to blame for the mishandling by governments of climate change issues. As a former Treasury official and international civil servant, I have been surprised by the failure of economic departments in OECD member countries to audit the evidence bearing on climate change issues, their uncritical acceptance of the results of a process of inquiry which is so obviously biased and flawed, and their lack of attention to the criticisms of that process which have been voiced by independent outsiders – criticisms which they ought to have been making themselves. A similar lack of resource has characterised the Research Department of the IMF and the Economics Department of the OECD. In all these departments and agencies, there has been a conspicuous failure of due diligence.


The chief moral to be drawn is straightforward. In an area of policy where so much is at stake, and so much remains uncertain and unsettled, policies should be evolutionary and adaptive, rather than presumptive as they are now; and their evolution should be linked to a process of inquiry and review which is more thorough, balanced, open and objective than has so far been the case.

Under the latter heading, two broad lines of official action could be followed. One is to focus on the IPCC process, by making it more professionally representative and watertight, while the other is to go beyond it. The more that can be done under the first heading, the less the need for action under the second. I believe that both can contribute, the more so since action under the second heading can be taken by national governments on their own account.

In his submission to the Review Committee, referred to above, David Holland has made 15 specific recommendations for improving the IPCC process. All of these are good suggestions. Here I would emphasise, in more general terms, three related aspects of reform, including but not confined to the IPCC. These are disclosure, inclusiveness and audit.

As to disclosure, two basic changes to IPCC practice should be made, with wider implications.

First, it should be clearly laid down, in the instructions to the Panel from its member governments, that no published work would qualify for consideration in the IPCC assessment process without evidence of proper archiving and full disclosure of data and code. Journal editors should be informed accordingly.

Second, governments should ensure that the IPCC assessment and review process actually conforms to the official requirement that it should be objective, open, and transparent. Specific proposals to that effect are made in David Holland’s submission.

Due disclosure would in itself promote greater inclusiveness, and both are required for more effective audit. With disclosure, non-subscribers to received opinion would be more fully informed and could no longer be easily disregarded or set aside; hence they would have better reason to take part in an assessment process which has become increasingly conformist with time. Nor is it just critics of prevailing scientific opinion who should be become more involved, with official knowledge and consent. There is an important role to be defined and made effective for neutral expertise, in the context of what has been rightly described as ‘the need for comprehensive audit of the quality of the science-based information on climate risk that is currently being used by governments to set public policy’.

More broadly, and going beyond the IPCC process, a new start is needed in the official handling of climate change issues. Neither the current official policy consensus nor the advice on which it rests should be treated as authoritative or final. Both should be seen, not as established doctrine, but rather as a body of working assumptions. As such, they should be made subject to rigorous testing and review; and it should be a leading concern of policy to ensure that such testing and review takes place. The whole notion of a now-settled consensus should be discarded. Governments should promote open exchanges of view and contrasting informed assessments. It should no longer be presumed either that the scientific debate is over or that the present official expert advisory process is professionally up to the mark, which it is not.

David Henderson, 7 June 2010