A review of ENSO theories

作     者：Chunzai Wang 

作者机构：State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences 

出 版 物：《National Science Review》 (国家科学评论(英文版))

年 卷 期：2018年第5卷第6期

页      面：813-825页

核心收录：

学科分类：07[理学] 070601[理学-气象学] 0706[理学-大气科学] 

基　　金：This research is supported by the National Natural Science Foundation of China(41731173) the Pioneer Hundred Talents Program of the Chinese Academy of Sciences,the Leading Talents of Guangdong Province Program,the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20060502) the National Program on Global Change and Air-Sea Interaction(GASI-IPOVAI-04) 

主　　题：ENSO ocean–atmosphere interaction climate variability 

摘      要：The El Nio and the Southern Oscillation(ENSO) occurrence can be usually explained by two views of(i)a self-sustained oscillatory mode and(ii) a stable mode interacting with high-frequency forcing such as westerly wind bursts and Madden-Julian Oscillation events. The positive ocean–atmosphere feedback in the tropical Pacific hypothesized by Bjerknes leads the ENSO event to a mature phase. After ENSO event matures, negative feedbacks are needed to cease the ENSO anomaly growth. Four negative feedbacks have been proposed:(i) reflected Kelvin waves at the ocean western boundary,(ii) a discharge process due to Sverdrup transport,(iii) western-Pacific wind-forced Kelvin waves and(iv) anomalous zonal advections and wave reflection at the ocean eastern boundary. These four ENSO mechanisms are respectively called the delayed oscillator, the recharge–discharge oscillator, the western-Pacific oscillator and the advective–reflective oscillator. The unified oscillator is developed by including all ENSO mechanisms, i.***.all four ENSO oscillators are special cases of the unified oscillator. The tropical Pacific Ocean and atmosphere interaction can also induce coupled slow westward-and eastward-propagating modes. An advantage of the coupled slow modes is that they can be used to explain the propagating property of interannual anomalies, whereas the oscillatory modes produce a standing oscillation. The research community has recently paid attention to different types of ENSO events by focusing on the central-Pacific El Nio. All of the ENSO mechanisms may work for the central-Pacific El Nio events, with an addition that the central-Pacific El Nio may be related to forcing or processes in the extra-tropical Pacific.