In the media, accurate climate information and climate disinformation often coexist and present competing narratives about climate change. Whereas previous research documented detrimental effects of disinformation on climate beliefs, little is known about how people seek climate-related content and how this varies between cross-cultural contexts. In a preregistered experiment, we studied how individuals sequentially sample and process Pro- and Anti-climate statements across 15 rounds. Participants from the United States, China, and Germany (N_total = 2226) freely sampled real-world climate-related statements, retrieved from Twitter and validated in previous studies. Overall, reading both Pro- and Anti-climate statements influenced climate concern in all countries. Participants preferred statements that were better aligned with their initial climate beliefs, and this confirmatory tendency intensified the more information had been sampled. Moreover, participants' confirmatory evaluation (i.e., accepting aligned and rejecting opposing messages) increased over time. While climate concern was mostly stable, in the United States, climate concern levels and box choices mutually reinforced each other, leading to greater polarization within the sample over the course of the experiment. The paradigm offers new perspectives on how people process and navigate conflicting narratives about climate change.