Students' understanding of the greenhouse effect, the societal consequences of reducing CO2 emissions and the problem of ozone layer depletion

This study is an attempt to contribute to the growing body of knowledge about students' conceptions and views concerning environmental and natural resource issues. Answers have been sought to the following questions: “How do Swedish students in grade 9 (15–16 years old) and grade 12 (18–19 years old) explain the greenhouse effect?”, “How do they think reduction of CO2 emission would affect society?” and “How do they explain that the depletion of the ozone layer is a problem?” The method chosen to answer these questions was to give students written tasks of the open-ended type. Five models of the greenhouse effect appear among the answers, all more or less incomplete, but nevertheless with potential for development. The students' responses also indicate that they do not fully understand what fundamental societal changes would occur as a result of a drastic reduction in CO2 emission. On the other hand, they are rather well informed about how injurious depletion of the ozone layer is to humans. The findings are discussed, including implications for teaching.