Environmental Review: Environmental Decision Making in the Face of Uncertainty

The purpose of this article is to help environmental practitioners deal with uncertainty. A simple model is presented that distinguishes between uncertainties about fact—past, present, and future—and indecision about what to do. To help environmental practitioners deal with these two problems, four tools or conceptual aides are presented. First presented is the “source of uncertainty” analysis method, which can help environmental practitioners understand the sources of uncertainty about facts. Second, a conceptual discussion of imprecise probability is presented to provide environmental practitioners with a method for understanding how to represent uncertainty quantitatively. The third tool presented is known as comprehensive life cycle analysis, which is a methodology to help environmental practitioners assess the full impacts of potential environmental decisions over multiple criteria and time. Fourth, a decision process framework is presented to help environmental practitioners understand when and how uncertainty and indecision can be attacked. The paper includes a discussion about how these four tools can be used by environmental practitioners to overcome seven common everyday problems they may face when confronted with the need to make environmental decisions under uncertainty. The paper also applies the four tools and relates the seven problems to the example of tropospheric ozone.