Abstract:
The response of tidal flats to storm surges is an important scientific problem in the evolution of tidal flats under climate change. To investigate the evolution of silt-muddy tidal flats in response to storm surges along the Jiangsu coast,the measured surface elevation of tidal flats pre-and post-storms and associated hydrological data were analyzed. The evolution of intertidal flats induced by storm surges is characterized by erosion in the upper intertidal flats while accretion in the lower flats. This is distinct from the evolution of sandy coasts which show erosion in the upper zones and accretion in the lower zones led by offshore sediment transport. A two-dimensional numerical model (Delft3D) is established considering tidal currents and sediment transport to simulate the bed evolution under calm and storm conditions,respectively. The hydrodynamic mechanism is explained for the regional characteristics of tidal flats,which shows an episodic effect on morphology after storm waves. The flood-dominated tidal current plays a key role on the long-shore sediment transport.