Search

The Radial Sand Ridges (RSRs) area in the southern Yellow Sea are subject to tropical and extratropical cyclone activities frequently, in which the special geometry feature and moving stationary tidal system result in complex storm-induced hydrodynamic processes, especially the tide-surge interactions. We studied a rare weather event influenced simultaneously by an extratropical cyclone EX1410 and Typhoon Vongfong as an example to investigate the characteristics of storm surges, wave-surge, and tide-surge interaction in the RSRs area, and applied a high-resolution integrally-coupled ADCIRC+SWAN model, in which the meteorological forcing inputs are simulated by the WRF-ARW model. The model is validated by records from 4 tide gauges and 2 wave buoys along the Yellow Sea coast. Results show that the tide-surge interactions are of considerable regional heterogeneousness. The surge curves at Lüsi (in south RSRs) and Jianggang (in middle RSRs) have abrupt falls near the time of low tide, where the peak occurrence time of interaction residuals tend to shift towards the mid-ebb period. Significant increase of bed shear stress in shallow waters was proved the dominant factor to affect the tide-surge interaction in broad tidal flats of the RSRs area. Differently, the interaction pattern in the Xiyang Trough (in north RSRs), showed a unique rising in mid-flood period due to the phase advances of real surge waves in relatively deep waters. Therefore, we suggested to the local flood risk management that the tide-surge interaction tends to alleviate the flooding risk in the RSRs area around the time of high tide, but aggravate the risk on the rising tide in the Xiyang Trough and on the falling tide in large-scale tidal flats of the southern RSRs area. [ABSTRACT FROM AUTHOR]

Because of the special topography and large tidal range in the South Yellow Sea, the dynamic process of tide and storm surge is very complicated. The shallow water circulation model Advanced Circulation (ADCIRC) was used to simulate the storm surge process during typhoon Winnie, Prapiroon, and Damrey, which represents three types of tracks attacking the South Yellow Sea, which are, moving northward after landing, no landing but active in offshore areas, and landing straightly to the coastline. Numerical experiments were carried out to investigate the effects of tidal phase on the tide-surge interaction as well as storm surge. The results show that the peak surge caused by Winnie and Prapiroon occurs 2–6 h before the high tide and its occurring time relative to high tide has little change with tidal phase variations. On the contrary, under the action of Damrey, the occurring time of the peak surge relative to high tide varies with tidal phase. The variation of tide-surge interaction is about 0.06–0.37 m, and the amplitude variations of interaction are smooth when tidal phase changes for Typhoon Winnie and Prapiroon. While the interaction is about 0.07–0.69 m, and great differences exists among the stations for Typhoon Damrey. It can be concluded that the tide-surge interaction of the former is dominated by the tidal phase modulation, and the time of surge peak is insensitive to the tidal phase variation. While the interaction of the latter is dominated by storm surge modulation due to the water depth varying with tide, the time of surge peak is significantly affected by tidal phase. Therefore, influence of tidal phase on storm surge is related to typhoon tracks which may provide very useful information at the design stage of coastal protection systems. [ABSTRACT FROM AUTHOR]