Origins of Quasi-Biweekly and Intraseasonal Oscillations over the South China Sea and Bay of Bengal and Scale Selection of Unstable Equatorial and Off-Equatorial Modes

作     者：Ying ZHANG Tim LI Jianyun GAO Wei WANG Ying ZHANG;Tim LI;Jianyun GAO;Wei WANG

作者机构：Ningde Branch of Fujian Meteorological BureauChina Meteorological AdministrationNingde 352100China 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 Department of Atmospheric SciencesSchool of Ocean and Earth Science and TechnologyUniversity of HawaiiHonoluluHI 96822USA 4Fujian Institute of Meteorological SciencesChina Meteorological AdministrationFuzhou 350001China Minhang District Office of Shanghai Meteorological ServiceChina Meteorological AdministrationShanghai 201199China 

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

年 卷 期：2020年第34卷第1期

页      面：137-149页

核心收录：

学科分类：07[理学] 0707[理学-海洋科学] 070601[理学-气象学] 0815[工学-水利工程] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0824[工学-船舶与海洋工程] 0825[工学-航空宇航科学与技术] 

基　　金：Supported by the National Key Research and Development Program of China(2018YFC1505805) US NOAA(NA18OAR4310298) US NSF(AGS-1643297) National Natural Science Foundation of China(41875069,41575052,and 41575043) Fund for Collaborative Innovation of Meteorological Science in East China(QYHZ201608) 

主　　题：quasi-biweekly oscillation(QBWO) intraseasonal oscillation(ISO) Madden–Julian oscillation(MJO) scale selection 

摘      要：The daily outgoing longwave radiation(OLR)field in boreal summer shows significant power spectrum peaks on quasi-biweekly(10–20-day)and intraseasonal(20–80-day)timescales over the Indo–western Pacific warm pool,especially over the South China Sea and Bay of *** quasi-biweekly oscillation(QBWO)originates from offequatorial western North Pacific,and is characterized by a northwest–southeast oriented wave train pattern,propagating *** intraseasonal oscillation(ISO),on the other hand,originates from the equatorial Indian Ocean and propagates eastward and *** the equatorial mode possesses a 20–80-day periodicity while the off-equatorial mode favors a 10–20-day periodicity is investigated through idealized numerical experiments with a 2.5-layer atmospheric *** the off-equatorial region,the model simulates,under a realistic three-dimensional summer mean flow,the most unstable mode that has a wave train pattern with a typical zonal wavelength of 6000 km and a period of 10–20 days,propagating *** is in contrast to the equatorial region,where a Madden–Julian oscillation(MJO)like mode with a planetary(wavenumber-1)zonal scale and a period ranging from 20 to 80 days is *** experiments with different initial conditions indicate that the QBWO is an intrinsic mode of the atmosphere in boreal summer in the off-equatorial Indo–western Pacific region under the summer mean state,while the MJO is the most unstable mode in the equatorial region.