Topographic and Hydrodynamic Influence on Rip Currents and Alongshore Currents on Headland Beaches in China

Feng, X.; Dong, B.X.; Ma, G.F., and Feng, W.B., 2020. Topographic and hydrodynamic influence on rip currents and alongshore currents on headland beaches in China. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 468–473. Coconut Creek (Florida), ISSN 0749-0208.Headland beaches are one of the most typical beaches in southern China. Meanwhile, southern China seas experienced severe rip current hazards. In this paper, numerical simulations were carried out by utilizing Delft 3D Flow-Wave coupling model. Ideal topography of different headland beaches was established and the variabilities in the rip currents' forms and the hydrodynamics from the major headland beach patterns were discussed, including the relative headland length (α= Lhead/Lbeach), the curvature of shoreline (k = Ls/Lc), the wave direction (θ) and the wave height (hs). Results revealed that four factors, including α, k, θ and hs, all have some influences on the nearshore circulation. The shape of the coastline influenced the position of alongshore current and the appearance of headland rip. The length of headland and the wave height influenced the intensity and the spatial distribution of nearshore circulation mainly. Besides, wave direction was the most important factor for channel rip. Because it played a decisive role in the generation of channel rip.