The Intergovernmental Panel on Climate Change - the definitive source of information on climate change - published its AR4 2007 synthesis report on 17 November 2007. This combines the findings of the first three reports (the physical science basis; impacts and adaptation; mitigation), all of which are also available on the IPCC website in full and summary version. The available stages of the report are: Working Group I Report: The Physical Science basis See here for the full report. Working Group II Report: Impacts, Adaptation and Vulnerability See here for the full report. Working Group III Report: Mitigation of Climate Change See here for the full report (pre-copy edit version). Working Group IV Synthesis Report. See here for more details.