USING MODELS IN AN UNCERTAIN WORLD

Although the utility of modeling has not been always widely accepted, current sentiment is more akin to “what, if not a model?” This practical view notwithstanding, periodic assessments of model utility can assist their application to societal goals, especially in the context of decision making.

Heat and pathogen transport modeling are considered in this talk as they relate to contributions by Ken Bradbury. There is widespread agreement that future climates will tend toward warming, but how such change affects aquatic systems is not well understood. Likewise, understanding pathogens in drinking water continues to be important for assessing water supply quality. New capabilities for watershed-scale heat transport simulation such as linking MODFLOW and MT3D-USGS and conceptual frameworks for colloid movement have advanced our understanding. New insights often lead to new questions, however, such as the appropriateness of simplifying assumptions. Recent research on heat and pathogen transport illustrates the need to revisit established thinking, and underscores the importance of decomposing modeling problems into the salient parts. From this, we argue for a broadminded approach to applying models to an uncertain world – one that embraces hypothesis testing using field data, forecast sensitivity, and the use of simple techniques to illustrate robust model findings.