南京信息工程大学张文君团队，报道了周期性和非周期性厄尔尼诺事件中独特的西风爆发特征及其与西太平洋海温异常的关系。相关论文于2024年9月25日发表于国际顶尖学术期刊《大气科学进展》杂志上。

厄尔尼诺—南方涛动(ENSO)是热带太平洋海洋—大气系统的一种涛动，被认为是由高频随机大气扰动所激发的。在这些扰动中，西风爆发(WWBs)通过产生向东传播的下降开尔文波和抑制赤道太平洋东部的温跃层，对ENSO的发展起着至关重要的作用。目前的工作阐明了在周期性和非周期性ENSO事件期间WWBs的不同季节性演变，以及它们与局地海表温度(SST)异常的关系。对于非周期ENSO事件，在发展中年份的春季，赤道太平洋中西部盛行WWBs。

相反，在ENSO事件发展到夏季之前，未能观测到活跃的WWBs。在非周期性和周期性ENSO事件发展的春季，高频WWBs和相关的局部深层对流出现显著差异。这些差异与赤道中西部太平洋局部海温异常密切相关，通过激发大气深层对流，在ENSO相关的热带太平洋中东部大尺度海温异常充分表现之前。

研究人员观测显示，在一个耦合的大气环流模式中真实地再现了，非周期和周期性ENSO事件的WWBs差异及其与赤道中西部太平洋海温异常的关系。该研究从ENSO循环的角度阐述了全球变暖与ENSO之间的复杂联系，从而加深了人们对ENSO发展的理解。

附：英文原文

Title: Distinct westerly wind burst feature in cyclic and non-cyclic El Nino events and its association with western-central Pacific SST anomalies

Author: Yu Liu, Wenjun Zhang, Zhuolin Xuan, Feng Jiang, Suqiong HU

Issue&Volume: 2024-09-25

Abstract: El Nio-Southern Oscillation (ENSO) is an oscillation of the ocean-atmosphere system in the tropical Pacific, which is argued to be energized by high-frequency stochastic atmospheric disturbances. Among these disturbances, westerly wind bursts (WWBs) play a crucial role in the development of El Nino by generating eastward-propagating downwelling Kelvin waves and suppressing the thermocline in the central-eastern equatorial Pacific. The present work elucidates distinct seasonal evolutions of WWBs during cyclic and non-cyclic El Nino events, and their association with the local sea surface temperature (SST) anomalies. For non-cyclic El Nino events, WWBs prevail over the western-central equatorial Pacific during spring of the developing year. In contrast, active WWBs cannot be observed until developing summer for cyclic El Nino events. Significant differences in high-frequency WWBs and associated local deep convection appear in the developing spring season of non-cyclic and cyclic El Nino events. These differences are closely linked to local SST anomalies in the western-central equatorial Pacific via exciting atmospheric deep convection, preceding the full manifestation of ENSO associated large-scale SST anomalies in the central-eastern tropical Pacific. The observed difference in WWBs for non-cyclic and cyclic El Nino events and its association with the western-central equatorial Pacific SST anomalies are realistically reproduced in a coupled general circulation model. This study enhances our comprehension of El Nino development by illustrating the intricate connection between WWBs and El Nino evolution in the ENSO cycle’s perspective.

DOI: 10.1007/s00376-024-4056-3

Source: http://www.iapjournals.ac.cn/aas/article/doi/10.1007/s00376-024-4056-3