The psychological underpinnings of collective climate action

We are in the midst of a dangerous climate crisis, and collective mobilization is needed to push for urgent global transformations. Many people already perceive the risk that human actions are driving increasingly catastrophic climate impacts, but only a few are taking actions such as asking governments for climate policy, educating peers, and implementing community-based models of ecological transition. This dissertation examines the psychological drivers of collective climate action among young adults, beginning with the pivotal role of climate risk perception and investigating a dozen additional theorized psychological motivators. Chapter 2 reports a systematic review of 228 publications (2010–2024), in which thirteen psychological factors associated with collective climate action were mapped. The cognitive and emotional facets of risk perception emerged as the factors most consistently associated with collective climate action: awareness of the anthropogenic climate crisis and concern about its impacts. Chapter 3 examines whether the perception of the risk that human actions drive catastrophic climate impacts, by itself, leads to greater climate engagement; in a Registered Report, a brief educational video intervention increased self-reported (but not physiological) risk perception of human emissions. While self-reported risk perception alone did not significantly increase climate engagement, it predicted engagement when participants believed their climate actions could have an impact (collective efficacy). Chapter 4 explores the causal role of other psychological factors (including, but not limited to, risk perception) in promoting collective climate engagement through two programmatic Registered Reports. These studies tested a longitudinal intervention on university students in Italy and the Netherlands, manipulating twelve theorized psychological motivators and measuring the resulting change in behavior. Multiple psychological factors increased, as did short-term collective actions such as advocacy, activism, civic engagement, and educational behaviors. The belief that societal transformations are likely to emerge from the grassroots (a bottom-up 5 theory of change) emerged as a robust predictor of collective climate action across studies and contexts, along with collective efficacy and other more study-specific factors such as emotional engagement, self-efficacy, cognitive alternatives and collective identity. The drivers of collective action identified by this dissertation may help bridge the gap between climate risk perception and collective behavioral engagement.