Public Underst. Sci. 25, 656–673 (2016)

Conveying uncertainty remains a major challenge for scientists. In an attempt to aid lay readers in interpreting its latest report, the IPCC used a 'calibrated language' to communicate the likelihood of key findings. The effectiveness of that strategy largely depends on it being understood and reported to a wide audience.

Luke Collins and Brigitte Nerlich from the University of Nottingham, UK, conducted a text analysis of how this language was used by the English-speaking media when reporting the IPCC's Working Group I Summary for Policymakers.

They found that 141 of 1,906 articles in the dataset implicitly referred to the IPCC's calibrated language, with only 30 making explicit reference to the likelihood scales. Reporters often chose to use analogies rather than the calibrated language, comparing the science of climate change to knowledge that smoking causes cancer, for example. The concepts of 'certainty' and 'consensus' were also often conflated.

This suggests that the IPCC's efforts to clarify uncertainty through a calibrated language only had a small impact on wider communication of key climate science findings.