Environmental impact assessment by experts in cases of factual uncertainty

Abstract

This study deals with the difficulty that there is usually incomplete knowledge and data about an ecosystem and its environmental-economic interactions, thus hindering the development of a quantitative model for impact assessment. The method brings together a panel of experts and draws on their interdisciplinary expert knowledge of that and similar environmental systems. The panel 'creates' what its members view as likely data which describe instances of the causal relationship(s) under investigation. These artificial data are processed by standard statistical methods to identify the best formal model(s) describing the relevant relationship(s). The model can then be used to estimate environmental impacts caused by various expected external developments (investments projects, environmental policy, and so on). An application to a project in Greece is discussed.