利用WW3模式实现中国周边海域波浪能流密度数值预报——以2次冷空气过程为例

Wave Energy Density Forecast in China Seas by WW3 Wave Model:A Study Based on Two Cold Air Events

近年来中国在海洋能研究方面得到快速发展,但目前为止尚未实现波浪能的预报。本研究以T639预报风场作为WW3(WAVEWATCH-III)海浪模式的驱动场,对2013年3月发生在中国周边海域的2次冷空气过程所致海浪场进行模拟,充分利用来自朝鲜半岛、日本、台湾岛的观测资料,检验WW3模式对能流密度的预报能力,实现了波浪能流密度的数值预报,为海浪发电、海水淡化等波浪能开发工作提供保障。研究表明:1)以T639预报风场驱动WW3海浪模式,可以较好地预报冷空气影响下的中国周边海域波浪能流密度。无论预报值与观测值在曲线走势上,还是从相关系数、偏差、均方根误差、平均绝对误差等定量来判断,预报能流密度都具有较高精度,其中在朝鲜半岛、日本周边海域的预报效果好于台湾岛周边的预报效果。2)在冷空气影响下,中国周边海域的波浪能流密度伴有明显的增幅。在渤海、渤海海峡、黄海北部,由于海域狭小,海浪得不到充分成长,能流密度的增幅相对较小,大值区的范围也相对较小;冷空气进入黄海中部、东海后,能流密度迅速增加,高值中心可达80 kW/m以上;冷空气进入南海后,虽然也使得能流密度明显增大,但由于南海纬度较低,冷空气南下行进至南海后强度大为减弱,能流密度的大值区范围较东海缩小。

The wave field in China Seas in March 2013 was simulated by WW3 （WAVEWATCH-Ⅲ） wave model, with the T639 forecasting wind data as its driving field. The validation work was done byobserved data around the Korean Peninsula, Japan and Taiwan islands. The study is for the realization of forecasting wave energy density in China Seas. Results show that ： 1 ） With T639 forecasting winddata as driving field, wave energy density in China Seas can be simulated properly by WW3 wave model. Judged from forecasted and observed values in trend curves, or from CC, Bias, RMSE andMAE, high accuracy of forecast has been realized, with even more accuracy around the Korean Peninsula and Japan Islands than in surrounding waters of Taiwan. 2 ） Under the influence of cold air,wave energy density in China Seas increased obviously. In the Bohai Sea, the Bohai Straits and northem Yellow Sea, the waves did not grew fully due to narrow waters, with a relatively small increase inthe density. After the cold air entered into central Yellow Sea and East China Sea, the density increased rapidly, up to a value as high as 80 kW/m or even more. When the cold air entered into South China Sea, the density also increased significantly. However, due to sharp decrease in cold airstrength, the area with a high density is relatively smaller than that in East China Sea.