The role of climate change education on individual lifetime carbon emissions

education program exist, significant social and political challenges exist with most large-scale solutions to climate change. 7. Uncertainties and study limitations In the following section, we describe a number of uncertainties and study limitations that are important to the interpretation of the results. Although we believe the COMM 168 course provides unique insight into the long-term role that education can have on individual behav- iors, especially given the lack of existing studies that look at how education can shape behavior over many years, we also acknowledge the potential limits of such a research design, and thus we are careful here to identify uncertainties and describe limitations in the study. The exposure of such uncertainties and limitations provides the research with a context for interpreting the results and also provides an avenue for researchers to undertake additional studies to investi- gate the impact that education can have on long-term behavior change. 7.1. Uncertainties The study methodology and analysis include a number of assumptions that contribute to the uncertainties associated with this study, and these are discussed below. Student enrollment. Because the course is titled “Global Climate Change,” students inter- ested in environmental issues may have self-selected into the course. These students may respond more favorably to the course design, and may be more willing to change their behav- ior in the future given their initial interest in the environment. Although the impact of incen-

tives on bias is not clearly understood [52], the year-long course included a 3-unit incentive where a passing grade in the 9-unit course provided students with an additional 3 units of general education credit. We heard that many students reported that they signed up for the course because of the extra requirements satisfied. Further, we note that when this incentive was removed from the course design in 2014, the initial broad distribution of majors who enrolled in the class declined quite dramatically. In the earlier years with the 3-unit incentive (2007–2013), four colleges (i.e, Social Sciences, Humanities and the Arts, Business, and Health and Human Sciences) each had at least 10% of the registered students. However, once the 3-unit incentive was removed in 2014, only two colleges (i.e., Social Sciences, Humanities and the Arts) had significant enrollment (i.e., more than 10% of students), with the course now having more enrollment from Environmental Studies and Communication Studies. The 3-unit incentive thus appears to have been effective in drawing students from across campus, and this suggests that the course topic was not the only reason students enrolled in the course. Energy calculations. The household carbon footprint calculator was used to estimate how student responses would impact carbon emissions. Although the calculator has been used in a number of studies, various assumptions were made as described in Table 1 of S2 Text. It is clear that some of the carbon reductions attributed to the course experience may have inherent

uncertainties. For example, actions such as carpooling regularly, making food choices to reduce emissions and buying energy-star appliances all suggest actions to reduce emissions, and yet the actual reduction amount depends on specifics of the action that are difficult to obtain without a more detailed survey tool. In contrast, the goal of this analysis was to docu- ment actions attributable to the course and develop a practical methodology for estimating the carbon reductions using the best tools available. Behavior changes. Another uncertainty that this research only partially uncovered was the motivation for the reported changes. Did participants make lifestyle changes because of environmental concerns or for other reasons, such as financial considerations or ethical con- cerns? In our focus group, participants reported that pro-environmental outcomes were the The role of climate change education on individual lifetime carbon emissions PLOS ONE | https://doi.org/10.1371/journal.pone.0206266 February 4, 2020 17 / 23