Morphodynamic modeling and morphological upscaling in a fine sediment system

Abstract

Sediment mobility and memory effects distinguish transport and morphodynamics in fine sediment settings from sandy settings. This paper focuses on the morphodynamic modeling of fine sediment systems, and an adaptation of modeling procedures more commonly used in sand-dominated systems. An extensive dataset of short-term transport and morphological trends along with ancillary data is used to support the development, parameterization, and calibration of a morphodynamic model of the Lower Passaic River (USA). The model is subsequently extended to include a morphological acceleration procedure in order to enable computationally efficient morphodynamic simulations. The performance of the resulting model is first verified and subsequently validated using measured decadal-scale morphological change. Subsequently, the model is used to assess the current morphodynamic status and the long-term response of the river to forcings such as shipping, episodic storm events, and climate change, with results that are consistent with theoretical expectations.