Propagation of planetary-scale zonal mean wind anomalies and polar oscillations  

作　　者：QIAN WeiHong LIANG HaoYuan 

机构地区：[1]Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China

出　　处：《Chinese Science Bulletin》2012年第20期2606-2614,共9页

基　　金：supported by the National Natural Science Foundation of China(40975039)

摘　　要：Global atmospheric variables can be physically decomposed into four components:(1) the zonal time averaged climate symmetric component,(2) the time averaged climate asymmetric,(3) the zonal-mean transient symmetric anomaly,and (4) the transient asymmetric anomaly.This study analyzes the relationships between the intra-seasonal and inter-annual variability of planetary scale decomposed zonal and meridional winds in the tropopause,and oscillations such as those from the El Ni o-Southern Oscillation (ENSO),the Arctic Oscillation (AO) and the Antarctic Oscillation (AAO).The tropical inter-annual zonal mean wind anomalies in the tropopause are linked with the ENSO cycle and can propagate into the subtropics,mid-latitudes,and polar front regions via abnormal meridional vertical cells.Similarly,tropical intra-seasonal (40-60-d) zonal wind anomalies can reach the subtropics and mid-latitudes.The polar intra-seasonal zonal wind anomalies in the tropopause can propagate toward high-latitude areas.Thus,the AO and the AAO are the result of the interaction and propagation of these planetary scale zonal wind anomalies.Global atmospheric variables can be physically decomposed into four components：（1） the zonal time averaged climate symmetric component,（2） the time averaged climate asymmetric,（3） the zonal-mean transient symmetric anomaly,and （4） the transient asymmetric anomaly.This study analyzes the relationships between the intra-seasonal and inter-annual variability of planetary scale decomposed zonal and meridional winds in the tropopause,and oscillations such as those from the El Ni o-Southern Oscillation （ENSO）,the Arctic Oscillation （AO） and the Antarctic Oscillation （AAO）.The tropical inter-annual zonal mean wind anomalies in the tropopause are linked with the ENSO cycle and can propagate into the subtropics,mid-latitudes,and polar front regions via abnormal meridional vertical cells.Similarly,tropical intra-seasonal （40-60-d） zonal wind anomalies can reach the subtropics and mid-latitudes.The polar intra-seasonal zonal wind anomalies in the tropopause can propagate toward high-latitude areas.Thus,the AO and the AAO are the result of the interaction and propagation of these planetary scale zonal wind anomalies.

关 键 词：纬向风异常 行星尺度 平均风 传播 振荡 极地 ENSO循环 中纬度地区 

分 类 号：P467[天文地球—大气科学及气象学]