Why the effectiveness of simple messages about the scientific consensus on climate change has likely been overestimated

Simple consensus messages (e.g., “97% of climate scientists agree that human-caused climate change is happening.”) have been promoted as a scalable and effective intervention to correct misperceptions, strengthen belief in climate change, and increase support for public action. However, these claims may not be warranted because they are based on an experimental procedure that confounds updated beliefs with attempts to reproduce the exact percentage from the message. A reanalysis of data obtained using this procedure and a new experiment (2,414 participants from Germany, Switzerland, and Austria) substantiate the concern that the effectiveness of simple consensus messages has likely been overestimated. We discuss why giving participants information and asking about it later is unlikely to result in valid measurements of updated beliefs. Focusing on more directly meaningful outcomes, such as behavior aimed at mitigating the climate crisis, offers a promising way forward.