ESTEEM - A NEW ‘HYBRID COMPLEXITY’ MODEL FOR SIMULATING ESTUARY MORPHOLOGICAL EVOLUTION AT DECADAL TO CENTENNIAL SCALES

摘要

Better models capable of generating quantitative predictions of coastal morphological change at decadal to centennial scales are required if we are to bring scientific understanding to bear on management challenges of the 21st century. Despite an emerging consensus that progress is more likely to be made through models that are essentially synthesist in approach, the nature of marine forcing, especially in estuaries, means that it is frequently necessary to retain a degree of hydrodynamic complexity that can only be obtained via more reductionist models. We see great potential, therefore, in fusing these approaches rather than deploying them separately as end members of a modelling spectrum. This paper thus presents a novel approach to mesoscale estuary morphological evolution that combines physically complete 1D simulation of tidal channel hydrodynamics, highly parameterised 2D mechanistic representation of tidal flat sediment dynamics driven by fetch-limited waves, and more empirical representation of 2D variation in salt marsh morphodynamics.