Effect of Climate Change-Induced Tropical Cyclone Track Shift on Sedimentology in the East China Coastal Ocean

Tropical cyclones (TCs) significantly influence coastal sedimentation, geomorphologic features, and morphodynamic processes through strong winds, heavy rains, and storm surges. These effects are particularly pronounced in the east China coastal ocean. However, the impacts of poleward and landward shifts in TC tracks on sedimentology, specifically sediment transport and erosion-deposition processes, remain insufficiently understood. This study utilizes the Delft3D-FM numerical model integrated with TC best track data and field measurements to investigate sediment transport patterns under historical TC tracks and to quantify erosion responses to poleward and landward track shifts. From the historical sediment transport pattern derived from the typical historical TC track, results reveal that sediment in waters shallower than 30 m is highly sensitive to TC activity, with four distinct zones where net sediment transport is sensitive to the change of typical historical TC tracks. Coastal erosion depth changes due to poleward and landward shifts of typical TC tracks during the peak TC intensity period are quantified as 0.24–1.63 cm°N⁻¹ and 0.05–1.06 cm°E⁻¹, respectively. Under global warming scenarios, these values are projected to increase by 2.45%–8.00% and 4.71%–13.33%, respectively. Identifying the coastal areas more susceptible to TC-induced sediment transport and quantitatively assessing the effects of poleward and landward track shifts are important for understanding local TC variability and supporting research on sedimentology during TCs and the future protection of coastal areas.