2008 年 55 巻 p. 181-185
High waves attacked fishery harbours and towns faced the Japan Sea both in Niigata and Toyama prefectures on February 24, 2008 and brought sever damages in the breakwaters and houses. The generation mechanism of the high waves has been investigated using the weather charts, wind velocity data, wave and tide gage data. The significant wave heights reached about 6m or higher at many ports along the Japan Sea, especially, the waves with a wave height of 9.92m and period of 16s were observed at Toyama port and harrbour. Long period waves have also been observed under the condition of high wind speed and high waves and exited continental edge waves of 0-th to second modes. The weather conditions for generating abnormaly high waves called the Yorimawari Nami has also been investigated.