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Confidence and likelihood in the IPCC Fifth Assessment Report


About the fact sheet

When the IPCC scientists use the terms 'confidence' and 'likelihood,' each term has a different and very specific meaning relating to levels of certainty.

When scientists mention 'confidence', they are referring to the degree of confidence in being correct. In the case of the IPCC where scientists are analysing global climate, issues such as lack of observational data in certain regions, such as Africa, will affect scientists' confidence in their findings. When scientists mention 'likelihood' they are referring to the probability of an event or outcome occurring.

Further information