Rip current hazards in South China headland beaches

Abstract

Beaches and coastal regions are commonly primary tourist destinations. Dollars spent by beach visitors annually provide significant input to local and regional economies. Hazards associated with rip currents can influence the suitably of any given stretch of coast as a recreational resource, and thus impact tourist dollars spent in addition to the safety and well-being of beach visitors. Therefore it is crucial to evaluate the degree of rip current risk along recreational beaches in order to protect human lives, maintain tourist attraction, and aid beach managers. Accordingly, a new rip current hazard assessment method is proposed based on the beach state model. Using the measured morphodynamic parameters (wave parameters, tidal ranges and sediment grain size) of 51 South China beaches, a preliminary assessment of rip current hazards was carried out. Results show that 71% of South China beaches may develop rip currents. The beaches in southern Fujian, Shanwei (in eastern Guangdong) and western Guangdong, and eastern and southern Hainan coasts have the highest risk of rip current development. The evaluation results are consistent with remote sensing observations, and beach incident (drowning and near-drowning) media reports. This paper indicates that the beach morphodynamic model of Ω-RTR (dimensionless fall velocity-relative tidal range) is a reasonable method to assess the rip current risk along sandy beaches. This information can aid coastal managers as well as reduce the frequency of rip current related incidents.