INITIATION MECHANISMS FOR A SUCCESSIVE MJO EVENT AND A PRIMARY MJO EVENT DURING BOREAL WINTER OF 2000-2001  

作　　者：冯婧 李天明 

机构地区：[1]Key Laboratory of Meteorological Disaster,Ministry of Education / Joint International Research Laboratory of Climate and Environmental Change ,Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science and Technology [2]Beijing Meteorological Information Center,Beijing Meteorological Bureau [3]International Pacific Research Center and Department of Atmospheric Sciences,University of Hawaii at Manoa

出　　处：《Journal of Tropical Meteorology》2016年第4期479-496,共18页热带气象学报（英文版）

基　　金：China National 973 project(2015CB453200);China National project(41575070);NSFC(41475084);OLR(N00014-16-12260);NRL(N00173-13-1-G902);Jiangsu NSF Key Project(BK20150062);Jiangsu Shuang-Chuang Team(R2014SCT001);Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD);China Special Fund for Meteorological Research in the Public Interest(GYHY201306028);Colleges and Universities in Jiangsu Province Plans to Graduate Research and Innovation(CXLX13_486)

摘　　要：Observed outgoing longwave radiation(OLR) and ERA-Interim reanalysis data were analyzed to reveal the initiation processes associated with a successive and a primary MJO event during 2000-2001. It was found that the initiation of the successive event was caused by anomalous ascending motion induced by low-level horizontal temperature advection. The anomalous ascending motion, together with horizontal moisture advection, moistened lower troposphere and led to an unstable stratification and triggered convection. The initiation of the primary MJO event, on the other hand, was caused by the accumulation of anomalous moisture associated with three low-frequency modes, a convectively coupled Kelvin wave(CCKW), an westward-propagating equatorial Rossby wave(ER) and a weak planetary-scale MJO mode. It is the merging of the low-level specific humidity anomalies of the three modes that led to the rapid setup of large-scale convectively unstable stratification and favored the development of the eastward-propagating planetary-scale MJO mode.Observed outgoing longwave radiation (OLR) and ERA-Interim reanalysis data were analyzed to reveal the initiation processes associated with a successive and a primary MJO event during 2000-2001. It was found that the initiation of the successive event was caused by anomalous ascending motion induced by low-level horizontal temperature advection. The anomalous ascending motion, together with horizontal moisture advection, moistened lower troposphere and led to an unstable stratification and triggered convection. The initiation of the primary MJO event, on the other hand, was caused by the accumulation of anomalous moisture associated with three low-frequency modes, a convectively coupled Kelvin wave (CCKW), an westward-propagating equatorial Rossby wave (ER) and a weak planetary-scale MJO mode. It is the merging of the low-level specific humidity anomalies of the three modes that led to the rapid setup of large-scale convectively unstable stratification and favored the development of the eastward-propagating planetary-scale MJO mode.

关 键 词：CONVECTION INITIATION successive MJO PRIMARY MJO 

分 类 号：P433[天文地球—大气科学及气象学]