Intermodel Diversity of Simulated Long-term Changes in the Austral Winter Southern Annular Mode:Role of the Southern Ocean Dipole  

作　　者：Fei ZHENG Jianping LI Shuailei YAO 

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,Beijing 10029,China [2]Frontiers Science Center for Deep Ocean Multispheres and Earth System(FDOMES)/Key Laboratory of Physical Oceanography/Institute for Advanced Ocean Studies,Ocean University of China,Qingdao 266100,China [3]Laboratory for Ocean Dynamics and Climate,Pilot Qingdao National Laboratory for Marine Science

出　　处：《Advances in Atmospheric Sciences》2021年第3期375-386,共12页大气科学进展（英文版）

基　　金：This work was jointly supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA19070402);a National Key Research and Development Project(Grant No.2018YFA0606404);the National Natural Science Foundation of China(Grant Nos.41790474 and 41775090).

摘　　要：The Southern Annular Mode(SAM)plays an important role in regulating Southern Hemisphere extratropical circulation.State-of-the-art models exhibit intermodel spread in simulating long-term changes in the SAM.Results from Atmospheric Model Intercomparison Project(AMIP)experiments from 28 models archived in CMIP5 show that the intermodel spread in the linear trend in the austral winter(June−July−August)SAM is significant,with an intermodel standard deviation of 0.28(10 yr)−1,larger than the multimodel ensemble mean of 0.18(10 yr)−1.This study explores potential factors underlying the model difference from the aspect of extratropical sea surface temperature(SST).Extratropical SST anomalies related to the SAM exhibit a dipole-like structure between middle and high latitudes,referred to as the Southern Ocean Dipole(SOD).The role of SOD-like SST anomalies in influencing the SAM is found in the AMIP simulations.Model performance in simulating the SAM trend is linked with model skill in reflecting the SOD−SAM relationship.Models with stronger linkage between the SOD and the SAM tend to simulate a stronger SAM trend.The explained variance is about 40%in the AMIP runs.These results suggest improved simulation of the SOD−SAM relationship may help reproduce long-term changes in the SAM.

关 键 词：Southern Annular Mode Southern Ocean Dipole intermodel spread air−sea interactions 

分 类 号：P434[天文地球—大气科学及气象学] P732.6