Tell don’t ask: how to use social media to mobilise local collective climate action

Abstract Collective climate action may be vital for shaping societal-level change and alleviating climate anxiety. We examined how climate movements can utilise social media to promote local public engagement, as the language and social imagery used by climate activists could affect public willingness to engage. Collaborating with Extinction Rebellion (XR)-United Kingdom (UK), we conducted a randomised controlled field trial with over 350,000 Facebook users in three cities: Birmingham, Oxford, and Cardiff. We evaluated the impact of messaging and imagery on local climate engagement, by comparing willingness to attend climate talks based on requests versus exhortations, alongside protest, impact, and diversity images. We found that exhortations were more effective than requests, especially when paired with climate impact imagery. Message effectiveness varied across cities, being the strongest in Birmingham and weakest in Cardiff, indicating the importance of tailoring strategies to local contexts.