Intergovernmental Panel on Climate Change: Fifth Assessment Report: The Physical Science Basis (2013)

The first of three parts of the Fifth Assessment Report (AR5) focuses on the scientific evidence behind climate change and the human role in it. The Intergovernmental Panel on Climate Change (IPCC) has been meeting in Stockholm this week to discuss the final wording of the summary of Working Group One (WG1), which assesses the physical science, such as concentrations of greenhouse gases in the atmosphere, temperature rises and climate models. It has been written the world’s top climate scientists – 209 lead authors and 50 editors from 39 countries. This summary report will be followed by Working Group I’s full in-depth report on Monday, 30 September.

Set up in 1988, the IPCC is a United Nations body that evaluates the state of climate science. It produces major assessments every five-seven years. The last report, published in Paris in 2007, said that scientists were 90% certain that humans were responsible for global warming. The panel was awarded the Nobel peace prize in the same year, shared jointly with former US vice–president, Al Gore.

Working Group II’s report on Impacts, Adaptation and Vulnerability is scheduled to be released in mid March 2014, followed by Working Group III’s Mitigation of Climate Change in early April 2014. AR5 Synthesis Report (SYR) will be released in October 2014.

AR5 Media Portal
UN_ClimateTalks at Twitter
IPCC at Twitter
IPCC Fifth Assessment Report at Wikipedia
Live coverage by The Guardian (27 September)
Global warming likely to breach 2C threshold, climate scientists conclude (summary by Fiona Harvey for The Guardian)
FAQs answered by Adam Vaughan (The Guardian)

Report summary (28 pp, 2 MB, updated on 2015-2-6)
Full report (1535 pp, 375 MB, updated on 2015-2-6)
Press release (27 September 2013)
Other formats and translations (added on 2015-2-6)