A systematic review and meta-analysis of communication strategies to promote climate action

Achieving large-scale behavioral change and public support for ambitious climate policies are crucial components to the mitigation of climate change. Effective public communication strategies can help attain this goal. In a meta-analysis of experimental studies (71 publications, 481 effect sizes, n = 216′033) using mostly single-message exposure, we show that climate change communication strategies have a small positive effect of Hedges' g = 0.13, 95% CI [0.07, 0.18]. All but responsibility-focused strategies consistently increased climate-relevant intentions, behaviors, and policy support. Strategies promoting stronger emotional engagement, such as using storytelling or inducing awe related to the beauty of nature, appeared more effective than strategies merely communicating scientific evidence and facts. Moreover, using images as opposed to text increased the effectiveness of communication strategies, while studies adopting Open Science standards found somewhat smaller, more conservative, effects. Our findings provide robust evidence that most climate change communication strategies can be important instruments for shaping climate-relevant behaviors and policy support, especially when widely and repeatedly deployed.