In both these examples, the embedded clause (that global warming is serious) is presented as an opinion belonging to a source entity (scientists).
Our work is related to social psychology research on persuasion (Cialdini, 1993; Orji et al., 2015) and recent NLP research on argumentation, such as predicting argument convincingness (Habernal and Gurevych, 2016; Simpson and Gurevych, 2018) and studying discourse-level and non-linguistic features predictive of persuasion (Yang and Kraut, 2017; Zhang et al., 2016).