Climate change’s impacts on the oceans (“ocean change”) threaten people globally. Climate action is needed at multiple scales, from individual to collective action, and yet there is limited research on what motivates this action in response to ocean change. In this study, we conducted an online survey of residents of the state of Oregon, United States (n = 1414), to assess concerns, personal importance, and risk perceptions regarding ocean change and explore potential psychological cognitions to target in action-oriented communication efforts. Our latent class analysis identified four distinct audience subgroups ranging from individuals who are Doubtful (9 %) about ocean change to those who are Cautious (20 %), Concerned (33 %), and Alarmed (38 %). Audience subgroups varied in their climate action intentions and associated psychological cognitions (i.e., psychological distance, efficacy beliefs, social norm perceptions). The climate action intentions of the Alarmed and Concerned were positively predicted by all cognitions, those of the Cautious were significantly predicted by social norms (β = .15, p = .002) and efficacy beliefs (β = .34, p < .001), and those of the Doubtful were only predicted by efficacy beliefs (β = .23, p < .001). Across all four audiences, efficacy beliefs were strongly associated with intended climate action (β = .30, p < .001), suggesting efficacy beliefs may be a practical cognition to target in broad audience communication efforts on ocean change. These findings reinforce the importance of targeting specific psychological cognitions and, ideally, distinct audiences in ocean change communication efforts intending to motivate widespread climate action.