파랑후측에서 나타난 동해 유의파고의 선형추세

Linear trend of significant wave height in the East Sea inferred from wave hindcast

Extreme significant wave height (SWH) influences the coastal environment such as coastal erosion and damage to coastal structures. In this study, to investigate a long-term trend of SWH in the East Sea, a wave hindcast experiment for the East Sea was conducted by using the SWAN wave model forced with ECMWF reanalysis wind data during 40 years (1979~2018). Trends of SWH in the East Sea appear to significantly change spatially. For example, in August when typhoons pass most frequently through the East Sea, the monthly-mean SWH shows an increasing trend in the southern basin, while the SWH shows a decreasing trend in northern basin. The 99th percentile shows a different spatial pattern in the trend: an increase in the northwestern area and a decrease in the southeastern area. On the other hand, in December when strong northwesterly winds are dominant, both monthly-mean and 99th percentile SWH show an increasing trend in most of the East Sea. Especially, there is a noticeable increasing trend in the southeastern East Sea. Our results suggest that the long-term trends of the SWH in the East Sea significantly vary depending on seasons and locations.