Contrast of Evolution Characteristics of Boreal Summer and Winter Intraseasonal Oscillations over Tropical Indian Ocean

作     者：Qingchi ZHANG Tim LI Jia LIU 

作者机构：Key Laboratory of Meteorological DisasterMinistry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China International Pacific Research Center and Department of Atmospheric SciencesUniversity of Hawaii at ManoaHonoluluHawaii 96822USA 

出 版 物：《Journal of Meteorological Research》 (气象学报（英文版）)

年 卷 期：2019年第33卷第4期

页      面：678-694页

核心收录：

学科分类：07[理学] 0707[理学-海洋科学] 

基　　金：Supported by the National Key Research and Development Program of China(2018YFC1505804 and 2015CB453200) National Natural Science Foundation of China(41630423 and 41875069) US Natural Science Foundation(AGS-16-43297) US National Oceanic and Atmospheric Administration(NA18OAR4310298) School of Ocean and Earth Science and Technology(SOEST)contribution number 10740 International Pacific Research Center(IPRC)contribution number 1340 Earth System Modeling Center(ESMC)number 271 

主　　题：intraseasonal oscillation seasonality convection initiation and propagation planetary boundary layermoistening air-sea interaction 

摘      要：A most striking summer–winter difference of evolution of the intraseasonal oscillation(ISO)over the equatorial Indian Ocean is a quasi-stationary oscillation in boreal summer but eastward propagation in boreal *** feature is consistent with the observational fact that maximum ISO variance appears only in the eastern Indian Ocean in boreal summer while it appears across the entire basin in boreal *** cause of the distinctive propagation and initiation characteristics is investigated through the diagnosis of observational and reanalysis data for the period of 1982–*** is found that when the ISO convection appears over eastern Indian Ocean,a positive(negative)moisture tendency appears to the east of the convection in boreal winter(summer).It is the moisture tendency difference that is responsible for different propagation behavior in the summer and winter.A further diagnosis of the moisture budget indicates that the major difference lies in anomalous moisture advection by the mean *** addition,air–sea interaction also plays a *** boreal winter ISO starts over western Indian Ocean,boreal summer ISO is initiated over central–eastern equatorial Indian Ocean,due to boundary layer *** moisture increase is caused primarily by the horizontal advection of mean specific humidity by anomalous easterlies induced by preceding suppressed-phase ISO over eastern Indian ***,a delayed SST feedback also plays a *** overall difference of ISO evolution between the summer and winter is regulated by the seasonal mean state including the mean SST and water vapor content.