A basic understanding of climate politics is necessary for citizens to assess their government’s policies. Media use is supposed to enable learning, while widening knowledge gaps. We analyze whether such a gap opened up in times of intense media coverage during the 2015 climate conference in Paris and explain learning through hierarchical regression analyses, drawing on a 3-month panel survey ( n = 1121) in Germany. We find a diminishing knowledge gap: people with low previous knowledge catch up on the better informed, but overall knowledge remained low and learning was limited. This suggests a ceiling effect: possibly journalistic media did not provide enough new information for the well-informed. Closing knowledge gaps may also be explained by the media system with public television and regional newspapers reaching broad segments of the population. Higher knowledge was predicted less by media use than by education, concern, and being male.