Models in Fluvial Geomorphology

Models are conceptions of physical reality which can be employed to produce qualitative or quantitative predictions. Due to the complexity of natural systems, and gaps in our knowledge, the development of a model involves simplifying this physical reality to a form that fits the available resources and permits prediction of the phenomenon (ASCE Task Committee 1998). It is these models of restructured reality that are actually used and, as a general premise, there is often a discrepancy between physical reality (the ‘problem’) and the model. It is therefore incumbent on potential users to judge if in fact the model can provide predictions that are accurate enough to solve their particular problem. The primary aim of this chapter is to provide the information and guidance necessary to help users in making this judgement. The specific contents and scope of this chapter in relation to this aim are described at the end of this introduction. However, it is initially helpful to recognise the different motives of the various individuals who have formulated the fluvial geomorphological models that have been published and used by practitioners.