The worldwide rise of climate skeptical political leaders endangers sorely needed political efforts to mitigate climate change. In addition, climate skepticism expressed by the political elites may spread to the electorate, thus ultimately affecting mitigation actions at the population level. It is crucial to better understand the psychological mechanisms underlying elite influences on public opinion formation and polarization. Here we show how affective processes contribute to these top-down influences using longitudinal data in the context of the 2016 U.S. presidential election. Findings revealed a general decrease in climate change beliefs immediately after the presidential election (November 2016). We moreover found an increase in positive emotions and a decrease in negative emotions toward the Republican Party after the election of President Trump. Most importantly, the positive emotional shift towards the Republican Party mediated the decrease in climate change beliefs: Individuals with pronounced increases in positive emotions toward the Republican Party most strongly reduced their belief in climate change after the presidential election. The effect was intensified among Republican partisans, pointing towards a mechanism underlying political polarization. Using data based on a major real-world political event, our findings illustrate how partisans update their beliefs by referring to the positions of relevant political authorities. We moreover demonstrate how emotions drive top-down influences of political leaders on partisans’ opinions and beliefs. Finally, our findings reveal how intensified emotions can contribute to the aggravation of the public climate change divide.