Volume and surface area changes in estuaries and tidal inlets

In models such as ASMITA, equilibrium concepts are used within a mass balance framework to provide a goal for the system evolution in response to some perturbation. To-date this approach has assumed a model domain of fixed extent (in plan) and represented the changes in volume over time. Here we introduce the plan area as an additional free parameter. The motivation is to represent the response of estuaries and inlets as mobile features of the landscape within a terrestrial frame of reference and over relatively long time scales. The importance attached to estuarine habitats also creates a requirement to be able to predict how the spatial extent of such habitats changes over time.