Subjective causal scenarios for global environmental change

Two studies are presented that investigate the assumptions that risk evalua tion is based on subjective causal scenarios, and that the cognitive repres entation of global environmental risks is structured according to five caus al levels: human attitudes, human activities, emissions or pollutions, envi ronmental changes, and negative consequences. In study 1, 30 subjects liste d in free-response format causes, consequences, and remedial measures for 1 4 environmental risks. Differences between predictive and diagnostic infere nces were found: whereas subjects tend to assign immediate rather than medi ated causes, they predominantly assign negative consequences for humans, ir respective of the length of the causal chain that leads to these consequenc es. In study 2, 41 subjects judged the overall similarity between 25 enviro nmental risks. A multidimensional scaling analysis of these similarity judg ments replicates the theoretically assumed five causal levels. Results of b oth studies support the assumptions that risk evaluation is based on implic it causal hypotheses and that the proposed five-level structure adequately describes the cognitive representation of environmental risks.