摘要
利用1979—2017年共39 a欧洲中期天气预报中心(ECMWF)海表面10 m风场资料,采用经验正交函数方法(EOF)、小波时频特征分析等方法分析了南海近海面风场变化特征及其对ENSO的响应。结果表明:南海近海面风场第一模态海表面平均风速呈减小趋势,呈现年代际变化,且与ENSO相关,但相关性在1990年后趋于减小;第二模态中南海北部和南部平均风速呈减小趋势,中部增大;第三模态中南海中部海表面平均风速趋于减小,北部和南部增大,第二和第三模态均表现为年际变化,且均与ENSO显著相关,近年来ENSO与第三模态的相关性逐渐增强。春季南海表面平均风速从南到北逐渐增加;夏季在越南沿岸部分海域仍有一个风速极大值中心,从该海域向四周逐渐减小,整片海域风向均是西南风;秋季由南向北依次增加;冬季南海整片海域风速都较大,越南沿岸和我国东沙群岛海域存在两个极大值中心。
Based on the data of sea surface wind field at 10 m from ECMWF （European Center for Medium-Range Weather Forecasts） from 1979 to 2017, the Empirical Orthogonal Function （EOF） method and wavelet time-frequency analysis are used to analyze the variation characteristics of near-surface wind field over the South China Sea and its response to ENSO. The results are as follows. For the first EOF mode of the near-surface wind field over the South China Sea, the average sea surface wind speed presents downtrend and interdecadal variations and is correlated with ENSO, but the correlation gradually decreases since 1990. For the second EOF mode, the average wind speed shows downtrend over the northern and southern South China Sea and uptrend over the central South China Sea. For the third EOF mode, the average sea surface wind speed gradually decreases over the central South China Sea and increases over the northern and southern South China Sea. Interdecadal variations are manifested in the second and third mode and are significantly correlated with ENSO. Recent years have witnessed the correlation increase between ENSO and the third mode. In spring, the average sea surface wind speed over the South China Sea gradually increases from south to north. In summer, there is a center of maximum wind speed over some sea areas of the coast of Vietnam, while the speed gradually decreases from these sea areas to the surrounding areas. Southwesterly winds prevail over these sea areas. In autumn, the speed successively increases from south to north. In winter, the wind speed is relatively large over the whole South China Sea, and there are two centers of maximum speed over the coast of Vietnam and the sea areas of Dongsha Islands.
作者
邹玮
徐峰
涂石飞
张馨文
季倩倩
陈思奇
张羽
ZOU Wei;XU Feng;TU Shifei;ZHANG Xinwen;JI Qianqian;CHEN Siqi;ZHANG Yu(College of Oceanography and Meteorology,Guangdong Ocean University,Zhanjiang 524088,China;South China Sea Institute of Marine Meteorology,Zhanjiang 524088,China;School of Atmospheric Sciences,Nanjing University,Nanjing 210023,China;Guangdong Climate Center,Guangzhou 510640,China)
出处
《海洋气象学报》
2018年第3期83-91,共9页
Journal of Marine Meteorology
基金
国家自然科学基金项目(41475120)
2016年广东省大学生创新项目
广东省自然科学基金重大基础研究培育项目(2015A030308014)
关键词
中国南海
近海面风场
ENSO
EOF分析
小波分析
the South China Sea
near-surface wind field
ENSO
EOF analysis
wavelet time-frequency analysis
