Modelling geomorphic systems: scaled physical models

Physical models are scaled representations of a full-scale physical system which can be applied to inform our understanding of geomorphic process-form interactions. Physical and experimental modelling has been used extensively and has been proven to be of critical importance to the geomorphological user. Physical models can be loosely divided into a number of categories: 1:1 replica models; Froude-scaled models; distorted scale models; and analogue ‘similarity of process’ models. The choice of physical model type is dependent on the researcher’s aims and objectives. Advantages include the ability to: (i) isolate variables within a controlled laboratory setting; (ii) incorporate actual physical processes rather than simplifications; (iii) study infrequent or hypothetical scenarios, and; (iv) extract qualitative and quantitative data. Users of physical models must be cautious of the potential shortcomings of using a physical model, such as scale and laboratory effects. Despite these shortcomings, physical models provide a useful technique to observe, visualise and measure process-form interactions. This permits an improved understanding of complex physical relationships which other modelling methodologies may not be able to simulate.