中国海的极端海浪强度变化及归因分析  

Trend and attribution analysis of extreme wave intensity in the China Sea

作　　者：王娟娟[1] 李本霞[1] 高志一[1] 侯放 王久珂[1] Juanjuan Wang;Benxia Li;Zhiyi Gao;Fang Hou;Jiuke Wang(National Marine Environmental Forecasting Center,Beijing 100081,China)

机构地区：[1]国家海洋环境预报中心,北京100081

出　　处：《科学通报》2021年第19期2455-2467,共13页Chinese Science Bulletin

基　　金：国家重点研发计划(2017YFA0604901,2018YFC1407001)资助。

摘　　要：海浪作为海洋上主要的动力过程,其极端强度的时空变化正在得到越来越多的关注.为了获得中国海的极端海浪强度的长期时空变化趋势,并研究导致该变化的主要原因,采用欧洲中期天气预报中心最新发布的ERA-5海浪和大气再分析资料,使用Sen斜率估计和Mann-Kendall趋势检测方法,分析中国海的极端海浪强度(此处用有效波高的99.5%百分位数表征)在年际、台风浪和冷空气浪盛行期的历史40 a(1979~2018年)变化趋势.并通过对极端风速以及热带气旋数量和强度的变化趋势分析,研究导致中国海极端海浪变化的原因.分析结果表明,东海南部海域的极端海浪存在十分显著的年际增强趋势,幅度可达+5 cm/a,与其在台风浪盛行期的增强趋势及幅度一致,而极端风速在年际和台风浪盛行期的增强趋势是直接原因.此外,影响东海南部的强台风和超强台风的数量也存在显著增加趋势,这也导致了该海域极端海浪的恶劣程度加剧.同时,南海南部的极端海浪在年际、台风浪和冷空气浪盛行期均存在增强趋势,幅度最大+3 cm/a,而极端风速的增强是直接原因.As one of the most important dynamic processes in the ocean,ocean waves and the spatiotemporal variations in their extreme intensity are receiving increasing attention.To determine the variation characteristics of extreme wave intensity in the China Sea and analyze the main reasons for the variations,ERA-5(released by the European Center for Medium range Weather Forecasts,ECMWF)wave and atmosphere reanalysis data are used.Based on a large number of buoy wave observation data,the accuracy of the ERA-5 significant wave height reanalysis data is evaluated.Then,the Sen slope estimation and Mann-Kendall trend detection methods are applied to analyze the temporal and spatial trends of extreme wave and average wave intensity in the China Sea over the past 40 a(1979-2018).The interannual trend and the trends during typhoon wave prevailing period(June to October)and cold air wave prevailing period(November to March of the following year)are analyzed by Sen and Mann-Kendall methods.In addition,by analyzing the trends of extreme sea surface wind speed in the China Sea,the causes of extreme wave intensity changes are investigated.The number and intensity of tropical cyclones that affect the south of the East China Sea,where the extreme wave intensity has altered significantly,are also analyzed for the attribution analysis.Herein,the 99.5% percentile of the significant wave height is used to characterize the extreme wave intensity.The analysis results show that:(1)The accuracy and stability of ERA-5 wave reanalysis data in the China Sea are very high,with the root mean square error of 0.264 m,relative error of 12.65%(when significant wave height is not less than1 m),scatter index of 22.96%,and correlation coefficient of 0.956.(2)Regarding the trend of the average wave intensity,a significant interannual enhancement trend of significant wave height in the East China Sea and the South China Sea are observed,with the maximum amplitude of the trend being+0.5 cm a^(-1).(3)The variation trend of extreme wave intensity denotes that

关 键 词：极端海浪 中国海 极端风速 热带气旋 变化趋势 

分 类 号：P731.22[天文地球—海洋科学]