摘要
赤道太平洋西风爆发事件(简称“西风事件”)对厄尔尼诺有重要的触发作用。基于ERA-Interim和NCEP2(NCEP-DOE Reanalysis 2)风场资料以及OI(NOAA OI SST V2 High Resolution Dataset)海表面温度资料,本文对西风事件的时空特征进行了研究诊断,并初步分析了ENSO(El Nino-Southern Oscillation)对西风事件的影响。结果显示,西风事件发展初期主要集中在中西部太平洋,季节性变化表现为冬春季较强,夏秋季较弱。西风事件频次和强度都有一定的年际变化特征,其中中太平洋西风事件的强度与ENSO信号的关系更紧密。当Nino3.4指数大于1℃时,西风事件的频次和强度与ENSO信号相关性好;当Nino3.4指数小于1℃时,西风事件频次的随机性增加,但其强度仍受到赤道中东太平洋海温异常信号的制约。
Westerly wind burst(WWB)is vital in triggering the El Niño event in the equatorial Pacific.Based on the wind from the ERA-Interim and NCEP2 reanalysis and sea surface temperature(SST)from the NOAA OI dataset,we first diagnose the characteristics of typical WWB events and investigate the coherence between WWBs and sea surface temperature anomalies in the equatorial Pacific.Our results show that WWB events mainly occur in the middle and west Pacificregions.Furthermore,WWBs exhibit a significant seasonal cycle with a strong amplitude;they frequently occur in spring and winter,and weaker ones occur in summer and autumn.Meanwhile,the frequency and amplitude of WWBs display a strong interannual signal,closely following the SST variability in the central equatorial Pacific.When the Niño 3.4 index is higher than one degree Celsius,WWB occurrence and amplitude are tightly correlated with SST anomalies.When the Niño 3.4 index is smaller than one degree,WWB events occur randomly,and the modulation of WWB amplitude by SST anomaly is weak but still detectable.
作者
庄镇
郑建
王法明
ZHUANG Zhen;ZHENG Jian;WANG Fa-ming(Institute of Oceanology,the Chinese Academy of Sciences,Qingdao 266071,China;University of theChinese Academy of Sciences,Beijing 100049,China;Key Laboratory of Ocean Circulation and Wave,theChinese Academy of Sciences,Qingdao 266071,China;Laboratory for Ocean and Climate Dynamics,PilotNational Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China)
出处
《海洋科学》
CAS
CSCD
北大核心
2022年第5期1-9,共9页
Marine Sciences
基金
国家自然科学基金项目(41776035)
山东省自然科学基金项目(ZR2021MD024)。
关键词
西风爆发
天气扰动
厄尔尼诺
海气相互作用
westerly wind burst
weather disturbances
El Niño
air-sea interaction
