IPCC reflects scientific consensus on climate change

What The Science Says:
Claims that the IPCC does not accurately represent the views and findings of the scientists, on whose work the IPCC reports are based, are not supported by the facts. Ironically, it's those who are mispresenting Hulme's paper that are the ones being misleading.

Climate Myth: The IPCC consensus is phoney
'The UN’s Intergovernmental Panel on Climate Change misled the press and public into believing that thousands of scientists backed its claims on manmade global warming, according to Mike Hulme, a prominent climate scientist and IPCC insider.  The actual number of scientists who backed that claim was “only a few dozen experts,” he states in a paper forProgress in Physical Geography, co-authored with student Martin Mahony.' (Lawrence Solomon)

It seems ironic that one key version of this argument – that the IPCC ‘misleads’ by misrepresenting the science of climate change and its potential consequences  - is itself a gross misrepresentation of a statement made by Professor Mike Hulme, a climate change scientist who works at the University of East Anglia. He was also co-ordinating Lead Author for the chapter on ‘Climate scenario development’ for the IPCC’s AR3 report, as well as a contributing author for several other chapters. This is how Hulme dismissed the claim:

"I did not say the ‘IPCC misleads’ anyone – it is claims that are made by other commentators, such as the caricatured claim I offer in the paper, that have the potential to mislead."

The same argument also has a broader scope, demonstrated by the claim that within the IPCC, there is a politically motivated elite who filter and screen all science to ensure it is consistent with some hidden agenda. This position turns the structure of the IPCC into an argument, by claiming that the small number of lead reviewers dictate what goes into the IPCC reports.

Before considering this argument in full, it is prudent to observe that the IPCC does no science or research at all. Its job is purely to collate research findings from thousands of climate scientists (and others working in disciplines that bear on climate science indirectly, such as geology or chemistry). From this, the IPCC produces ‘synthesis reports’ – rather like an executive summary – in which they review and sum up all the available material.  It is necessary therefore to have an organisational structure capable of dealing efficiently with so much information, and the hierarchical nature of the IPCC structure is a reflection of this requirement.

How does the process work? The IPCC primarily concerns itself with science that has been published in peer-reviewed journals, although, as it makes clear in the IPCC’s published operational appendices, it does also use so called ‘grey’ material where there is insufficient or non-existent peer-reviewed material available at the time the reports are prepared. See IPCC principles, Annex 2: Procedure for using non-published/non-peer-reviewed sources in IPCC reports. Many people are involved in this complex process:

“More than 450 Lead Authors and more than 800 Contributing Authors (CAs) have contributed to the Fourth Assessment Report (AR4)".

Source: The role of the IPCC and key elements of the IPCC assessment process, February 2010

To suggest the IPCC can misrepresent the science belies the fact that such misrepresentations would be fiercely criticised by those it misrepresented. Considering how many lead authors and contributors are involved, any egregious misrepresentation would hardly remain unremarked for very long.

The Broader Consensus

As with all such disputes, it is helpful to consider if there is any evidence of credible independent support for the reports the IPCC has produced, and the conclusions those reports contain. If the accusations were true, such misrepresentation would also be problematic for official bodies, particularly national science academies and the like.

On that basis, it is reassuring to note that nearly every major national scientific body e.g. the Royal Society (UK) or the National Academy of Sciences (US), unreservedly supports the work and findings of the IPCC. An expanded list can be found here, including this statement:

“With the release of the revised statement by the American Association of Petroleum Geologists in 2007, no remaining scientific body of national or international standing is known to reject the basic findings of human influence on recent climate change”.

In 2010 an independent investigation of the IPCC was launched. Conducted by the InterAcademy Council, which represents the world’s scientific academies, the report highlighted a number of organisational and procedural areas that the council felt could be improved. However, the recommendations did not detract from the council’s appreciation of the IPCC’s work:

“The Committee found that the IPCC assessment process has been successful overall. However, the world has changed considerably since the creation of the IPCC, with major advances in climate science, heated controversy on some climate-related issues, and an increased focus of governments on the impacts and potential responses to changing climate”.

Source: IAC Report Executive Summary

Like all organisations, the IPCC can improve on its performance. Recent defensiveness regarding errors or ambiguities in the AR4 report may be mitigated in light of unpleasant attacks on the organisation and its director, but the criticisms are valid none the less.

However, claims that the IPCC does not accurately represent the views and findings of the scientists, on whose work the IPCC reports are based, are not supported by the facts.

Basic rebuttal written by GPWayne

Update July 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial


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