Wintertime extreme storm waves in the East sea (Japan sea): Estimation of extreme storm waves in the Toyama bay, Japan

摘要

In the winter East Sea (ES), abnormal high waves due to the cold and dry East Asian winter monsoon and winter storms (extratropical cyclones) are often reported causing large coastal damages along the coasts of ES. In February 2008, abnormal storm waves due to a developed atmospheric low pressure system propagating from the west off Hokkaido, Japan, to the south and southwest throughout the ES caused extensive damages along the central coast of Japan and along the east coast of Korea. In this study, we investigate a potential extreme storm wave, Yorimawari Waves in Japanese, in the Toyama Bay where the coastal structures were heavily damaged by the storm waves in February 2008. Three factors for wind wave growing, such as wind intensity, duration and fetch, are investigated for their extreme conditions based on historical data and empirical formula. Then, numerical experiments are conducted to estimate extreme wave characteristics in the Toyoma Bay using a meso-scale non-hydrostatic meteorological model, WRF, and a spectral wave model, WAVEWATCH III. The results from numerical experiments depict the potential significant wave height of 6.78 m and corresponding wave period of 18.28 sec at the Fushiki-Toyama Port in the Toyama Bay.