Climate change communication on 4chan’s /pol/ board 2015-2019: An automated content analysis

4chan.org is a popular imageboard Web site based on an unrivalled culture of anonymity. In the past, 4chan has often gained the public spotlight for its role in harbouring alt-right extremism, antisemitism and white supremacism, particularly within the controversial board /pol/, a forum dedicated to political discussions with over 140,000 posts per day and millions of unique monthly users globally. In response to a growing interest in online communication on climate change, this paper applies automated content analysis through probabilistic topic modelling to analyse how the online discourse around climate change has evolved on this platform over a five-year period between 2015 and 2019. Analysing a sample of 216,525 /pol/ posts, this study finds that, despite its reputation as a platform dominated by hate speech, discussions on climate change among /pol/ users remain primarily based on scientific content. However, this appears to be on a reversing trend, as discussions on race and nationalism are steadily overtaking scientific narratives. This paper also finds that a specific type of nationalism, labelled as climate nationalism is on the rise on this platform. Lastly, this study shows that interest in the status of scientific consensus on climate change, often considered a staple of discussions on climate change, is progressively falling in relevance