The Intergovernmental Panel on Climate Change
(IPCC) released on 27 September the first instalment of its eagerly anticipated Fifth Assessment Report (AR5). As with past reports, this one is likely to spark ongoing discussion about the threat from climate change and how to deal with it. But what is the IPCC and what exactly does it do?What is the IPCC?
The IPCC is an intergovernmental body established by the United Nations Environment Programme
and the World Meteorological Organisation
in 1988 to provide the world with a clear statement of the current scientific knowledge of climate change, and potential environmental and socio‑economic impacts.
Open to all member countries of the United Nations, the IPCC currently has 195 member countries. Representatives from these countries review and endorse the contents of IPCC reports before publication.Work of the IPCC
The IPCC does not conduct its own research nor does it monitor climate-related data. Rather, it reviews and assesses recent scientific, technical and socio‑economic information relevant to the understanding of climate change. From this published material, it creates its reports. Thousands of scientists worldwide contribute to the IPCC's work on a voluntary basis.
One of the main activities is to prepare comprehensive Assessment Reports about the state of knowledge on climate change, its causes, potential impacts and possible responses. The IPCC also produces Special Reports and Technical Papers on specific issues.
The first IPCC Assessment Report was published in 1990. Subsequent reports were produced in 1995, 2001 and 2007. There was some controversy after the release of AR4
in 2007 over the inclusion of some errors. For example, because of a mistaken claim that Himalayan glaciers could melt away by 2035
, the IPCC was accused in some quarters
of a lack of rigour, and of using sources that were not peer-reviewed. However, the number of confirmed errors in the report is small considering that the document ran over 3000 pages and incorporated over 6000 peer-reviewed studies. Nevertheless, the criticism prompted a review
of, and subsequent changes to, processes and procedures.
Inevitably, the IPCC has been the target of criticism from both ends of the spectrum of opinions about climate change. For some
, it is seen as overly cautious and conservative. Others
view it as a green-dominated, extremist organisation. Both groups criticise the process by which reports are produced. So what is the process?
IPCC assessment reports are produced in three volumes, each of which is prepared by a 'working group'. Working Group One (WGI) examines scientific evidence for climate change and the extent to which human activity is the cause. WGII focuses on the impacts of climate change, and how plants, animals and humans can adapt. WGIII focuses on climate mitigation
—that is, measures to reduce greenhouse gas emissions and enhance carbon 'sinks' which absorb greenhouse gases.
Reports are prepared by IPCC 'lead authors', who are experts selected by the IPCC Bureau, based on nominations by governments and observer organisations. The process
for preparing each report is governed by comprehensive procedures.
A first draft is prepared by authors based on an assessment of all relevant scientific information. Priority is given to peer-reviewed literature. To deal with uncertainty, the scientists use very defined language
to express varying levels of confidence in their conclusions.
There is then a multi-stage review process. Expert reviewers and governments are invited to comment on the accuracy and completeness of the content. Review editors ensure that all comments are taken into account by the author teams. After the first draft has been reviewed, authors prepare a second draft report which includes a 'Summary for Policymakers'. The second draft and the summary are then reviewed by both governments and experts. Authors then prepare final drafts of the report and summary. These are distributed to governments who provide comments on the draft summary. All reports must be endorsed by the relevant Working Group and a meeting of the IPCC before final publication.
For example, the first stage of AR5 had 209 lead authors, 50 review editors and more than 600 contributing authors. The first draft received 21,400 comments from 659 experts, and the second received 31,422 comments from 800 experts and 26 governments.
All of this takes time, and some
critics have suggested that the laborious six-year process is too slow, rendering reports out-of-date before they are published, and that in this fast-moving field, information should be released more frequently. What next?
AR5 will be released in four parts. The first part focusses on the physical science basis of climate change. The second part will be released in March 2014 and will focus on climate change impacts, adaptation and vulnerability. The third section, examining mitigation of climate change, is due in April 2014. The final Synthesis Report in October 2014 will integrate the material contained in previous three parts.
Post authored by Sophie Power