Empirical shoreline evolution modeling for Nha Trang beach

Abstract

Empirical data-driven models are increasingly being used to simulate shoreline evolution over time scales ranging from days to decades. For the empirical shoreline evolution modeling, the combined longshore and cross-shore modeling demonstrate the ability to improve the prediction skills for shoreline changes. This study focuses on the feasibility of the combined model with a case study of the embayed beach shoreline of Nha Trang, Vietnam. Nha Trang’s climate is dominated by the tropical monsoon climate, so the beach changes here are strongly affected by this typical climate. The combined model applied in this study is a coupling of the cross-shore model and a longshore model. The combined model can provide the seasonal shoreline position fluctuations induced by the longshore contribution. Besides, it is realized that the very mild waves in summer induce strong accretion which the model cannot simulate. Therefore, a small modification of the equilibrium Dean number (Ω0) in the ShoreFor cross-shore model is suggested to improve the accretion simulation.