Responses of the Southern Ocean mixed layer depth to the eastern and central Pacific El Niño events during austral winter

作     者：Yuxin Shi Hailong Liu Xidong Wang Quanan Zheng Yuxin Shi;Hailong Liu;Xidong Wang;Quanan Zheng

作者机构：School of OceanographyShanghai Jiao Tong UniversityShanghai 200240China Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Greater Mekong SubregionYunnan UniversityKunming 600650China College of OceanographyHohai UniversityNanjing 210098China Department of Atmospheric and Oceanic ScienceUniversity of Maryland at College ParkCollege Park 20742USA 

出 版 物：《Acta Oceanologica Sinica》 (海洋学报（英文版）)

年 卷 期：2024年第43卷第7期

页      面：1-14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：The Oceanic Interdisciplinary Program of Shanghai Jiao Tong University under contract No.SL2021ZD204 the Sino-German Mobility Program under contract No.M0333 the grant of Shanghai Frontiers Science Center of Polar Science(SCOPS) 

主　　题：Southern Ocean mixed layer depth Central Pacific El Niño Eastern Pacific El Niño Rossby wave train 

摘      要：Based on the Ocean Reanalysis System version 5(ORAS5)and the fifth-generation reanalysis datasets derived from European Centre for Medium-Range Weather Forecasts(ERA5),we investigate the different impacts of the central Pacific(CP)El Niño and the eastern Pacific(EP)El Niño on the Southern Ocean(SO)mixed layer depth(MLD)during austral *** MLD response to the EP El Niño shows a dipole pattern in the South Pacific,namely the MLD dipole,which is the leading El Niño-induced MLD variability in the *** tropical Pacific warm sea surface temperature anomaly(SSTA)signal associated with the EP El Niño excites a Rossby wave train propagating southeastward and then enhances the Amundsen Sea low(ASL).This results in an anomalous cyclone over the Amundsen *** a result,the anomalous southerly wind to the west of this anomalous cyclone advects colder and drier air into the southeast of New Zealand,leading to surface cooling through less total surface heat flux,especially surface sensible heat(SH)flux and latent heat(LH)flux,and thus contributing to the mix layer(ML)*** east of the anomalous cyclone brings warmer and wetter air to the southwest of Chile,but the total heat flux anomaly shows no significant *** warm air promotes the sea ice melting and maintains fresh water,which strengthens *** results in a shallower *** the CP El Niño,the response of MLD shows a separate negative MLD anomaly center in the central South *** Rossby wave train triggered by the warm SSTA in the central Pacific Ocean spreads to the Amundsen Sea,which weakens the ***,the anomalous anticyclone dominates the Amundsen ***,the anomalous northerly wind to the west of anomalous anticyclone advects warmer and wetter air into the central and southern Pacific,causing surface warming through increased SH,LH,and longwave radiation flux,and thus contributing to the ML ***,to the east of the anomalous anticyclone,there is n