<p>Public opinion research provides consistent evidence of the relationship between political orientation and public attitudes towards climate change. Nonetheless, less is known about contextual factors explaining the differences across contexts in this relationship. In this paper, we focus on the role of public opinion salience, measured in terms of aggregate-level proportion of “climate change” answers to the “most important problem” question, as a contextual factor. By employing multilevel linear regression models—including both between-countries and within-country estimators—on Eurobarometer data (six rounds, from 2008 to 2021), we find cross-sectional and longitudinal evidence of the moderating role of public salience of climate change in explaining the relationship between political orientation and the perceived seriousness of climate change. Specifically, differences in climate change concern among people with different political orientations are larger when public salience of climate change is higher—across countries—and grow larger as public salience increases—within a country.</p>