A series of 40‐year significant wave height (SWH) data were extracted from the ERA‐Interim data set of the European Center for Medium‐Range Weather Forecasts (ECMWF), for the Beibu Gulf and its adjacent waters in the South China Sea from 1979 to 2018. After that, data were first aggregated to annual and monthly average data. Through the analysis, the annual SWH had grown since 1984, reached a significant level in 1995, and reached a maximum 1.068 m in 2011. The monthly SWH values between April and September were lower than those of other months. Additionally, the corresponding analysis on wind speed data demonstrated that variation in wind speed was consistent with SWH from 1979 to 2018, but the overall trend of SWH increased while wind speed decreased. The decrease of wind speed could be attributed to the weakening of the East Asian monsoon, and the westward swell induced by the gales that occurred in the northeast of the South China Sea resulted in the increase of SWH in the study area. Finally, a multiple sine function decomposition neural network (MSFDNN) was employed to forecast monthly SWH over the next 10 years. The predicted results revealed that the MSFDNN was well‐performing for forecasting monthly SWH.

中文翻译：

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南海北部湾重大波高的分析与预测

从欧洲中程天气预报中心（ECMWF）的ERA-中期数据集中提取了一系列40年的重要波高（SWH）数据，这些数据分别来自北部湾和南海附近海域1979年至2018年。此后，首先将数据汇总为年度和月度平均数据。通过分析，每年的SWH值自1984年以来一直在增长，在1995年达到了可观的水平，并在2011年达到最大值10.68m。4月至9月的月度SWH值低于其他月份。此外，对风速数据的相应分析表明，从1979年到2018年，风速的变化与SWH一致，但SWH的总体趋势是增加而风速降低。风速下降可能是由于东亚季风减弱，南海东北部大风造成的向西隆升导致研究区域的西南偏北海域增加。最后，使用多正弦函数分解神经网络（MSFDNN）预测未来10年的每月SWH。预测结果表明，MSFDNN在预测每月SWH方面表现良好。