This paper investigates the social discourse about climate change as it manifests in social web contributions. A quantitative content analysis of such web contributions is presented. Two samples of web contributions were drawn; one from English and the other from Norwegian social web sources (e.g., blog entries, reader's comments to articles). Each sample consists of approximately 1000 text units (a text unit being defined as a piece of text expressing a coherent thought or line of argument). Each text unit was coded by two trained raters according to a coding scheme which was derived from the literature on climate change risk perception (Bassarak, Pfister, Böhm, 2017; Böhm & Pfister, 2017; Keller, Bostrom, Kuttschreuter, Savadorid, Spence, & White, 2012; Lorenzoni & Pidgeon, 2006). The coding scheme captured whether the following aspects of climate change (CC) were expressed in the text unit: (a) uncertainty of scientific evidence about CC, (b) controversial character of the societal discourse about CC, (c) impacts of CC and their seriousness, (d) moral evaluations of CC, (e) emotional reactions to CC, (f) the text unit author’s mode of reasoning (intuitive vs. deliberative). Results show few differences between the English and the Norwegian samples. Overall, the scientific uncertainty and the controversial nature of climate change are expressed only to low degrees. Furthermore, several discursive communities could be identified that differ in the extent to which they address climate science versus societal aspects of CC, the certainty versus inconclusiveness of scientific evidence concerning CC, and CC risks versus moral and emotional aspects of CC. Results are discussed in terms of the social amplification of risk and processes of polarization through filter bubbles.