Examination of Generation Mechanism of Abnormal Waves caused by the Monsoons along the Central Coast of the Japan/East Sea

Abstract

Hindcasts of three abnormal wave events in the central Japan/East Sea in winter in 1991, 2003, and 2008 were conducted by using a meso-scale meteorological model (MM5) and a third generation spectral wave model (WW3) to make clear the generation mechanism of the abnormal waves caused by winter monsoons. It is reported that coastal damages due to winter depression in 2008 were more serious than those in 1991 and 2003 and major damages of coastal structures in Toyama Bay in 2008 were caused by large wave-overtopping with a high sea level due to superposition of diffractive waves (form NW) and swells (from NE). It is clear in this study that the superimposition of developed wind waves and swells in the offshore region of the central Japan/East Sea makes the characteristics of abnormal high waves.