Motivating the political will necessary for fair and ambitious climate change policies is significantly complicated by the rise of populism. Right-wing populist communication targets civil servants and intellectuals as conspirators furthering a climate agenda for their own self-interest. Yet, despite the real world implications of populist communication, more work is needed to both (1) understand the presence of populist frames in media communication on climate change and (2) untangle the relationships between the far-right and diverse forms of climate skepticism. Completing a content analysis of newspaper opinion pieces and Fox News programing between 2008 and 2020, I find that populist skeptic frames are an important part of media communication on climate change in both the Wall Street Journal and Fox News. Additionally, I find that populist skeptic frames most commonly use process skeptic claims, leveraging conspiratorial language to describe collusion between the government and scientists to falsify the severity of climate change and control the public for their own gain. Using a survey experiment, I find that higher populist attitudes are negatively associated with both belief in climate change and support for climate mitigation policies among Republicans. Conversely, I do not find a significant effect of exposure to a populist process skeptic frame, prompting the need for more work on the connections between populist skeptic framing and climate change attitudes.

It is seemingly accepted that a democracy functions better with a reasonably informed citizenry. As we cannot acquire knowledge about a complex reality on our own, democratic societies operate through a set of institutions of which two are attributed the explicit task to assist citizensa legitimate pathway to knowledge. These institutions include news media and science. Evidence from recent years indicates that more and more elected politicians across the democratic world engage in attacks towards these institutions, with the deliberate aim to undermine their legitimacy. Because the functionality of news media and science essentially relies on their legitimacy, this trend has raised societal concerns in parallel with scholarly interest. While recent research has made important contributions to better understand political attacks towards institutional knowledge providers, several dimensions are still understudied. This thesis addresses such dimensions. Using quantitative content analysis, the research conducted in this thesis explores prevalence, party distribution and expressions of delegitimizing criticism (characterized by a presence of incivility and/or absence of reasoning) towards news media and science(conceptualized as epistemic authorities) among tweeting Members of Parliament (MP) in Sweden. The study analyzes single tweets by all Swedish MPs represented in the national parliament (and on Twitter) over a one-year study period (31st of October 2020 - 31st of October 2021) (N = 1828). Results from the exploration show that Swedish politicians engage in delegitimizing evaluations of epistemic authorities in a small and concentrated scale. Findings are several; Swedish politicians are remarkably more hostile towards the news media than towards science;one party affiliation contribute to more than half of all delegitimizing evaluations; delegitimizing criticism takes on several expressive forms but addresses to a large extent dimensions surrounding poor quality and partiality. The conducted study contributes to research about political hostility towards institutional knowledge providers in empirical and theoretical regards and provide entrances for further discoveries. A special request for futureresearch is to engage in more in-depth and detailed assessments of dimensions having been explored, for example by mixing in qualitative methods.