A Study on a Predictive Index for Dangerous Rip Current Generation at Haeundae Beach

Abstract

Haeundae beach draws one million visitors every summer season, and more than 100 people are rescued from rip currents every year. Beachgoers are unexpectedly carried away seawards, as far as 50 similar to 100 meters from shore, where swimming is restricted for safety reasons. Rescuers have strengthened lookout measures at several spots where dangerous rip currents have occurred. The determination of a predictive index for rip currents is vitally important for the protection of human life. Such an index allows governmental agencies to issue rip current warnings directly to the public, and allows for the establishment of preventative measures according to the magnitude of the rip current threat. We apply a modified rip current predictive index suitable for Haeundae - using wave height, wave period, and incident wave angle from the north. Compared with wave data acquired for the summer of 2011, the result of NERiPS-H (NEarshore Rip current Predictive System at Haeundae) index is reasonable and appropriate. Unfortunately, we have insufficient observed wave data. So, our NERIPS-H method has insufficient reliability. This lack of wave data will be addressed by additional intensive field surveys. Additional intensive field experiments were carried out at Haeundae Beach from June to August, 2012 for the collection of data. This in-situ measurement data will be used to improve the reliability of rip current predictive guidance.