How the Copenhagen Diagnosis came to be written

The Copenhagen Diagnosis was written by 26 climate scientists, all active researchers, from 8 countries. The group of authors is independent and unaffiliated with any organization. They speak only for themselves, not for the Intergovernmental Panel on Climate Change (IPCC) or anyone else. A core of lead authors established the broader group, drawing in experts across the range of topics covered in the report. About half are IPCC authors, with first hand experience in preparing such an assessment and an understanding of the scientific standards it should meet. The report is firmly based on the more than 200 cited peer-reviewed papers.

The aim of the authors was to write a readable, short, authoritative report summarizing the relevant peer-reviewed climate change research appearing since the cut-off publication date (about mid-2006) for papers assessed in the most recent (2007) IPCC assessment report. Like IPCC, the Copenhagen Diagnosis authors insisted on being policy-relevant but policy-neutral. Because there has been so much important recent research, the need for such a report was identified in order to inform the negotiations in Copenhagen in December 2009. It seemed obvious that somebody ought to prepare such an update, so the 26 authors took it upon themselves to do so. The veracity and value of this report rests entirely on the scientific credibility of its authors as well as that of the peer-reviewed publications cited throughout. Any errors or shortcomings in the report are also the sole responsibility of the 26 named authors.

The report is the culmination of about a year’s work by the group. Many of the authors met in Copenhagen in March 2009 to organize the work and to agree on deadlines, topics, chapter lengths, and so on. In deciding who would be in the group of authors, the primary criterion was scientific expertise on one or more of the various topics that needed to be covered. Scientists were sought who have excellent and sustained research reputations, who were willing and able to work to deadlines, fluent in English, and able to function as part of a writing team. Typically, one or two authors would draft a given chapter, then several others of the group would review and revise it, and finally the entire group would consider the revised draft and reach a consensus.

The Climate Change Research Centre at the University of New South Wales in Sydney, Australia contributed some staff support, e. g., for developing the web site and technical editing.  A grant helped to pay some of the essential costs such as printing and travel to the meeting in Copenhagen. No external agency or individual had any influence on the contents of the report except the 26 authors. The authors of The Copenhagen Diagnosis all freely contributed their time and expertise. None were paid anything from any source to write this report.

In the Copenhagen Diagnosis, all editorial decisions such as the agreement to include “boxes” dealing with common misconceptions were made by the 26 authors. The author group also decided the scope of each chapter and how long each chapter should be. In short, the authors had complete autonomy to design and write the report.
The Copenhagen Diagnosis is not a repudiation of the IPCC process or the 2007 IPCC assessment report. The authors simply considered that the significance of very recent research, and of many climate observations made after the last IPCC assessment was written, together with novel and important improvements in several areas of scientific tools and technology, all deserved to be brought to the attention of the Copenhagen negotiators, the media, governments, corporations and the global public in 2009.  The goal has been to make our report accessible to all: it is freely available online and copies can be distributed widely. 

The Copenhagen Diagnosis is about climate change science, not policy. For example, the report summarizes recent research underpinning the scientific rationale for large and rapid reductions in global greenhouse gas emissions, in order to reduce the likelihood of dangerous human-induced climate change. However, the authors have no political or policy agenda, and do not speak to the issue of formulating policies to achieve such reductions in emissions. As scientists, when climate change research is relevant to public policy, the authors consider it important to bring that research to the attention of the wider world; sound science can and should inform wise policy. This conviction led this team of 26 climate experts to write The Copenhagen Diagnosis.

Second edition now available from Elsevier

Cover, 2nd edition

To obtain a copy of The Copenhagen Diagnosis Second Edition go to the Elsevier web site.


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Citation: The Copenhagen Diagnosis, 2009: Updating the world on the Latest Climate Science. I. Allison, N. L. Bindoff, R.A. Bindschadler, P.M. Cox, N. de Noblet, M.H. England, J.E. Francis, N. Gruber, A.M. Haywood, D.J. Karoly, G. Kaser, C. Le Quéré, T.M. Lenton, M.E. Mann, B.I. McNeil, A.J. Pitman, S. Rahmstorf, E. Rignot, H.J. Schellnhuber, S.H. Schneider, S.C. Sherwood, R.C.J. Somerville, K.Steffen, E.J. Steig, M. Visbeck, A.J. Weaver. The University of New South Wales Climate Change Research Centre (CCRC), Sydney, Australia, 60pp.


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