Linking Knowledge and the Readiness for Climate Action: Development and Validation of the Climate Change Knowledge Scale

Climate change poses an existential threat to humanity, with profound ecological, social, and health consequences. Beyond policy and structural transformations, effective mitigation and adaptation require widespread behavioural change. Knowledge about the causes, impacts, and solutions of climate change is therefore a key target of climate communication. Yet, the empirical role of knowledge in fostering climate action remains unclear, partly due to varying conceptualizations and limited psychometric quality of existing measures.To address these limitations, we developed the 15-item Climate Change Knowledge (CCK) scale using a mixed-methods approach that integrates expert input and psychometric validation. The scale captures three domains: ecological mechanisms, societal impacts, and mitigation/adaptation measures, reflecting content validity grounded in both scientific literature and real-world understanding.Based on a representative German sample (N = 10,377), the CCK scale demonstrated good factorial, convergent, divergent, and criterion validity. It captures climate-specific knowledge that is distinct from general/ environmental knowledge and risk perception, and it explains unique variance in readiness for climate action, particularly individual behaviour, policy acceptance and political participation beyond these constructs.The CCK scale provides a concise, domain-specific and empirically validated instrument for assessing climate-related knowledge. By clarifying construct boundaries and enabling precise tests of how knowledge relates to engagement, it supports theory development and evaluation of climate education and communication initiatives. In doing so, it strengthens the evidence base for policies and interventions that aim to promote climate action.