Revisiting Asymmetry for the Decaying Phases of El Ni?o and La Ni?a  

作　　者：CHEN Wei LU Ri-Yu Buwen DONG 

机构地区：[1]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences [2]National Centre for Atmospheric Science-Climate, Department of Meteorology, University of Reading

出　　处：《Atmospheric and Oceanic Science Letters》2014年第4期275-278,共4页大气和海洋科学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 41105046)

摘　　要：This study investigated the relationship be- tween the asymmetry in the duration of El Nifio and La Nina and the length of their decaying phases. The results suggested that the duration asymmetry comes from the long decaying ENSO cases rather than the short decaying ones. The evolutions of short decaying El Nino and La Nina are approximately a mirror image with a rapid decline in the following summer for the warm and cold events. However, a robust asymmetry was found in long decaying cases, with a prolonged and re-intensified La Nina in the following winter. The asymmetry for long decaying cases starts from the westward extension of the zonal wind anomalies in a mature winter, and is further contributed to by the air-sea interaction over the tropical Pacific in the following seasons.This study investigated the relationship between the asymmetry in the duration of El Ni?o and La Ni?a and the length of their decaying phases. The results suggested that the duration asymmetry comes from the long decaying ENSO cases rather than the short decaying ones. The evolutions of short decaying El Ni?o and La Ni?a are approximately a mirror image with a rapid decline in the following summer for the warm and cold events. However, a robust asymmetry was found in long decaying cases, with a prolonged and re-intensified La Ni?a in the following winter. The asymmetry for long decaying cases starts from the westward extension of the zonal wind anomalies in a mature winter, and is further contributed to by the air-sea interaction over the tropical Pacific in the following seasons.

关 键 词：ENSO asymmetry DURATION decaying phase 

分 类 号：P732[天文地球—海洋科学] P732.6