南海地区准单、双周震荡对“碧利斯”降水维持影响分析  

Effects of the Quasi-week Oscillation and Quasi-two Week Oscillation Over South China Sea on Rainfall Maintenance of Tropical Cyclone Bilis

作　　者：顾春利[1] 倪允琪[1] 徐幼平 成巍 

机构地区：[1]中国气象科学研究院,北京100081 [2]北京应用气象研究所,北京100029

出　　处：《暴雨灾害》2010年第1期7-13,共7页Torrential Rain and Disasters

基　　金：国家973项目"我国南方致洪暴雨监测与预测的理论和方法研究"(2004CB418300)资助

摘　　要：利用NCEP资料对2006年5—9月南海地区季风进行带通滤波,分析各频谱传播特征,研究热带气旋"碧利斯"登陆期间季风涌爆发原因及季风涌对其登陆后降水的影响。结果表明,"碧利斯"登陆维持期间在南海季风区高频振荡、准单周和准双周振荡相互作用下使季风涌爆发维持;影响南海地区的经向风的准单周、准双周振荡都有明显的自东向西传趋势,准单周振荡源地在菲律宾海区;南海地区准单周和准双周振荡对热带气旋"碧利斯"卷入气流有明显的加强作用,有利于"碧利斯"环流长时间维持。Low-frequency Oscillations characteristics of South China Sea Monsoon circulation and the influence of outbreak of monsoon surge on the rainfall and maintaining of tropical cyclone Bilis are studied by using the NCEP reanalysis data. The interaction of the high frequency, quasi-week oscillation and quasi-two week oscillation has led to the increase of the meridional wind in the South China Sea and the outbreak of South China Sea monsoon surge. The meridional wind affecting the South China Sea region has a clear trend of westward spread in the quasi-week and quasi-two week oscillation and the source of the quasi- week oscillation is in Philippine Sea. The low-frequency oscillation over South China Sea has enhanced cyclonic flow and the convergence of water vapor flux in the inland area. It has also strengthened precipitation and supplied condensation energy consumption and is beneficial to maintain tropical cyclone Bilis.

关 键 词：南海季风 准单周 准双周 带通滤波 降水维持 

分 类 号：P458.124[天文地球—大气科学及气象学]