An OpenMI-based combined model for alongshore sediment transport and shoreline change

This paper describes the extension of a state-of-the-art one-line model in terms of alongshore sediment transport rate by linking with a cross-shore profile model through the OpenMI-based Pipistrelle interface. In order to combine these two models, three additional modules (Drift Interpolation module, Vector-to-Scalar module and Orientation Updating module) need to be developed, so that the two models which are based on different assumptions, coordinate systems and set-ups can be linked seamlessly. The existing two models and the three new modules are able to work together as a whole composition (i.e. the combined model) based on the OpenMI standard. This combined model aims to improve the one-line model in terms of alongshore sediment transport and beach morphological response predictability. It adopts both the modified Coastal Engineering Research Centre, USA (CERC) formula and the Energetics approach to calculate the alongshore sediment transport. Tests at a real curved coast demonstrate that the model is numerically stable, effective in computing and able to give reasonable predictions of shoreline change. It demonstrates that further research on linking existing models is promising.