The Intergovernmental Panel on Climate Change is a body of about 2,000 scientists that came together under the auspices of the World Meteorological Organisation and the UN environment programme in 1988 to investigate global warming.
This year it shared the Nobel Peace Prize with former US presidential candidate Al Gore for its work over almost two decades in highlighting the issue of climate change.
How does it work?
The panel does not carry out its own research, instead it works by assessing published material and peer-reviewed scientific literature. Every five or six years it completes a report on the causes, potential impacts and options for adapting and mitigating climate change. Every paragraph of the lengthy reports is fought over line by line by delegations.
What is the IPCC 4th assessment report?
The report is a synthesis of three previous reports published this year by the panel that outlined the causes, consequences and possible remedies to combat climate change. This week's discussions in Valencia centred on agreeing a 26-page summary for policymakers and a slightly longer technical summary of a longer 3,000-page text.
What are the main findings in the summary for policymakers?
The summary concludes that the evidence for climate change is "unequivocal" and human activities since 1750 have contributed to the warming. Impacts of climate change are already evident and widespread and there is new evidence of adverse effects on polar and mountain communities. Even under the most stringent mitigation scenarios, further warming and some associated impacts are already unavoidable.
Why is this latest IPCC report important?
The report will be presented to environment ministers at a meeting in Bali on December 3rd when policymakers will attempt to create a successor to the Kyoto Protocol - the key international agreement created to limit greenhouse gases.