Abnormally High Waves induced by Typhoon Vongfong along the Eastern Coast of the Korean Peninsula

Abstract

Korean Peninsula has become vulnerable to increasingly frequent and strong typhoons approaching through the Yellow Sea and the East Sea. The typhoons are one of the threats to the coastal areas causing direct damages with increasing sea surface temperature and sea level rise due to global warming. The damages caused by waves and swells generated by anti-cyclonic winds from the recent typhoons prompted the Korean government to initiate two projects, development of coastal erosion control technology and investigation of large swell waves and rip currents for the southern and eastern coasts. During the typhoon Vongfong (2014), the highest wave recorded at Uljin (6 m) was 80 minutes after the highest wave at Samcheok (4.6 m), which is located further northwest. The measurement of abnormally high waves propagated both from East Sea and along the northern coast was unprecedented. The observed data at Busan, Uljin and Samcheok and a Simulation WAves Nearshore (SWAN) model were applied to analyze the unusually high waves on the eastern coast of Korea. The analyzed results showed that abnormally high waves at Uljin induced by typhoon Vongfong could be generated by the resonance effect that merged with lower energy waves propagated from the East Sea and higher energy waves propagated along the eastern coast from northwest, Samcheok.