本文使用欧洲中期天气预报中心(European Center for Medium Range Weather Forecasting,ECMWF)近30年(1982-2011年)全球再分析资料(ECMWF 40 Year Re-analysis Interim)中的风场及海浪场资料,对全球海表10m风场、有效波高、平均周期和平均波向进行了统计分析,并定义了一种计算季节变率的方法。研究发现,有效波高和平均周期均存在明显的季节变化,且北半球大洋比南半球大洋季节变化更为明显,印度季风区则例外。另外尝试用波龄揭示风浪、涌浪的分布特征,证实了全球海洋为涌浪占主导及太洋东部存在涌浪强化,同时发现了涌浪的分布在春夏季变化明显的特征。
In this study, we used the latest 30 years of wind and global wave field datasets of the European Center for Medium Range Weather Forecasting Reanalysis Interim (ERA-Interim) recorded from 1982 to 2011 to conduct statistical analyses of a 10-m wind field, significant wave height, mean wave period, and mean wave direction. Furthermore, we defined a method for calculating their seasonal variabilities. We determined that the significant wave height and mean wave period both have obvious seasonal variation and that the Northern Hemisphere ocean wave has greater variability than that of the Southern Hemisphere except for the Indian monsoon region. We then used wave age to determine the distribution of the wind sea and swell. The results indicate that the swell strengthened in the eastern part of the ocean and was dominant of the swell in the whole ocean. At last, we found obvious change in the distribution of swell in spring and summer.