Information on public opinion has lasting effects on second-order climate beliefs, but minimal and ephemeral effects on first-order beliefs

Across western democracies, pro-climate beliefs are widespread. Yet, vocal minorities contest scientific consensus about global warming. Perhaps as a consequence, the extent to which the public accepts global warming and climate action is often underestimated. Correcting this perceptual deficit has been proposed as a promising way to strengthen climate action, since knowledge of broad public consensus could motivate environmentally friendly behaviours, increase support for policy interventions, or shift perceptions of political feasibility. In a preregistered two-wave survey experiment in Germany, we provide a novel test of this strategy in a national context with already high pro-climate support, using real and comprehensive public opinion data. We find that exposure to this information can produce a lasting, significant increase in second-order beliefs (perceptions of public opinion) two weeks after treatment, especially among those who initially underestimated public support. However, the effects on first-order outcomes—policy feasibility perceptions, attitudes, and behavioural intentions—are small, short-lived, and largely non-significant. By demonstrating the boundary conditions of second-order interventions, our study suggests that their promise may be more limited than often assumed. These findings may highlight the potential need for more targeted, repeated, and context-sensitive approaches if second-order information is to meaningfully shift climate beliefs and behaviours. • Learning what others think about climate change boosts Germans’ perceptions of public belief in and support for policy action and climate change, with the effect lasting even two weeks later. • However, this information has no immediate or lasting positive effect on those individuals’ own beliefs, behavioural intentions, or policy preferences. • Those who find out that support for policy action on climate change is widespread may immediately think such policy action is more politically feasible and likely to be implemented, but this effect fades away over time.