The Intergovernmental Panel on Climate Change (IPCC) is the leading organization for the evaluation of climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) with the mandate to provide a source of sound scientific analysis of the research on climate change and its potential impacts. This body does not conduct any research themselves, but only analyzes the research of others. The scientists involved work on a voluntary basis and can be from any countries participating in the UNEP or WMO.
The IPCCs main activity is to publish special reports on issues that are pertinent to the implementation of the United Nations Framework Convention on Climate Change (UNFCCC). These reports are based mainly upon published and peer reviewed scientific literature. The process by which these reports are written, compiled, and published is extensive. I will outline this process in the following paragraphs.
The reports are written by chapter. Each chapter has one or two main authors who oversee the content of the entire chapter and are the ones to defend the chapter in any cases of peer disagreement or governmental review. The chapter is written by several lead authors and their work is supplemented by the aid of even more contributing authors whose job it is to create graphs and organize data for use by the lead authors. All of these authors are chosen from governmental lists of appropriate researchers, or by a task force who selects experts based on their relevant publications.
After all chapters are written and complied, the report goes through an arduous three part approval process. First, the report is put up for peer review and other researchers and scientists are given the opportunity to dispute the findings of the report. When disputes arise, it is the job of the main author(s) to defend their chapter of the report and correct any findings that are highly disputable or incorrect. This process lasts between 4 and 8 weeks and all comments are available for public viewing for several years after the peer review period has ended.
Next the report is put under government/expert review. This is where governments meet with the main authors to discuss and review the findings of the report. Since many of the experts are chosen by governmental officials, this is a time where the reconvene to review the work of the experts and give input on their findings. At this point governmental officials can make comments regarding the content of the report and thier opinions on its findings.
Finally, the report is put under government review. This is where the report is summarized for policymakers and overviews of chapter content are agreed upon. While the government officials ultimately make these decisions, the main authors are present to recommend the most important content and ensure that vital information is not left out of the summaries. If the governmental officials are not aided in the creation of summaries, they may fail to choose the information that is most pertinent for the chapter summaries.
These reports are published on a regular basis. Each new report notes where the science has improved since the last report was published. They also note where the science is lacking and needs to be researched further.