The Distributional Character Of The Wave Height In The East China Sea

Ocean wave is a small-scale surface gravity wave generated by wind, which can be divided into wind wave and swell wave. The main research of ocean wave is studying the mechanism of the generation, development, dissipation and spread process, building ocean wave model, calculating ocean wave elements according to the sea surface wind field, and then giving the simulation, hindcasting and forecast about ocean wave. Nowadays, the technique of ocean wave numerical simulation has developed very well. As few people had calculated extremes reckoning about the Bo Sea, the Yellow Sea and the East Sea of China, these regions are chosen as the object in this paper.Based on the previous work about numerical simulation and extremes reckoning of ocean wave, the wave model WAVEWATCHâ…¢is applied to simulate the waves in the East China Sea. QSCAT/NCEP blended wind data and the experimental wind data provided by NASA's JPL laboratory (JPL wind data) are used respectively in the calculation as input wind stress. Firstly, those wind data are checked up by the observations from the 22001and 21004 buoy in the East China Sea. The comparison shows that the blended wind data and JPL wind data have higher precision, and are suitable for the simulation. Secondly, significant wave heights from the simulation are also checked up by the observation. The result shows that the computed wave heights are satisfying with the observed. Though there is several big error at some time points, the simulated accuracy of the high wave is high, that lays the foundation for the calculation of the extremum. Characteristics of significant wave height's seasonal variation are analyzed, as well as the monthly average and annual average trend. Then, wave field in the East China Sea is simulated for 15 years, using the established ocean wave numerical simulation for the East China Sea. The multi-year-return wave height is calculated too. According to the simulated result, the distributional character of the multi-year-return extreme wave height is construed. The calculation of the multi-year-return significant wave height has an important significance, in the ocean engineering application, especially in the offshore area of china. Reasonable, accurate and reliable elements of the extreme wave can guarantee a safe and economical design, avoid excessively low design standards, so that the project will not encounter destruction and damage, and also avoid excessively high design standards that increase the project cost, affect economic efficiency. In summary, the research for extreme wave height of the East China Sea is very significant.