Characteristics of high waves observed at multiple stations along the east coast of Korea

Abstract. In recent several years, extremely high waves occasionally struck the Korean coast of the East Sea and caused severe coastal disasters almost every winter season. In this paper, characteristics of such high waves are reported by analyzing wave records collected at multiple stations along the east coast of Korea. Meteorological data obtained at relevant weather stations were also used in the analysis. The reason for appearance of the high waves was identified as the strong northeasters due to extra-tropical low pressure systems that had been rapidly developing in the East Sea. The general mechanism concerning the formation and spatial evolution of such strong low pressure systems was more clearly understood through the synthetic analysis of the wave and meteorological data. In particular, the influence of spatiotemporal features of the low pressure system on the resulting characteristics of the high waves was described in more detail in this study. Since the overall wave direction was also northeast, the first wave arrival time on the coastline became later for a wave station whose latitude is lower. At present, however, the arrival time of such high waves on the coast as well as their intrinsic characteristics such as wave height and period are not satisfactorily predicted by the daily weather forecast. Hence, it is necessary to enhance predictability of the high waves by investigating developmental mechanisms of the strong low pressure system in the winter season more thoroughly.