The Synthesis Report (SYR) of the IPCC Fifth Assessment Report (AR5) provides an overview of the state of knowledge concerning the science of climate change, emphasizing new results since the publication of the IPCC Fourth Assessment Report in 2007 (AR4). The SYR synthesizes the main findings of the AR5 (IPCC) based on contributions from Working Group I (The Physical Science Basis), Working Group II (Impacts, Adaptation and Vulnerability), and Working Group III (Mitigation of Climate Change), plus two additional IPCC reports (Special Report on Renewable Energy and Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation).
The AR5 SYR is divided into four topics. Topic 1 (Observed changes and their causes) focuses on observational evidence for a changing climate, the impacts caused by this change and the human contributions to it. Topic 2 (Future climate changes, risks, and impacts) assesses projections of future climate change and the resultant projected impacts and risks. Topic 3 (Future Pathways for Adaptation, Mitigation and Sustainable Development) considers adaptation and mitigation as complementary strategies for reducing and managing the risks of climate change. Topic 4 (Adaptation and mitigation) describes individual adaptation and mitigation options and policy approaches. It also addresses integrated responses that link mitigation and adaptation with other societal objectives.
The challenge of understanding and managing risks and uncertainties are important themes in this report. See Box 1 (‘Risk and the management of an uncertain future’) and Box 2 (‘Sources and treatment of uncertainty’).
This report includes information relevant to Article 2 of the UN Framework Convention on Climate Change (UNFCCC).