孟加拉湾低涡与南海季风爆发关系及其可能机理  

THE VORTEX OVER BAY OF BENGAL AND ITS RELATIONSHIP WITH THE OUTBREAK OF SOUTH CHINA SEA SUMMER MONSOON

作　　者：朱志伟[1,2] 何金海[1,2] 

机构地区：[1]南京信息工程大学,气象灾害省部共建教育部重点实验室,江苏南京210044 [2]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《热带气象学报》2013年第6期915-923,共9页Journal of Tropical Meteorology

基　　金：国家自然科学基金面上项目(41075068、40905044)共同资助

摘　　要：客观定义并统计了孟加拉湾低涡,确定了30年(1980—2009年)中的34个季风爆发性低涡(MOV),分析其与南海夏季风爆发的关系。分析结果表明:季节转换期内(4—5月)低涡以东移型和北移型为主,这些低涡对南海季风爆发起指示作用,是南海季风爆发的前兆信号,故确定为MOV;气候态下,MOV发生在南海季风爆发前十天。MOV发生在高的海表温度、小的纬向风垂直切变、强的赤道西风的背景环境中;其生成位置与孟加拉湾各区海温演变有关,同一时段内,MOV总是倾向于在海温较高的海域上生成;MOV生成的早晚与赤道西风的增强和发展有密切联系,"亚澳大陆桥"对流和南印度洋海温是影响MOV生成时间的重要因子。这些结论可为南海季风的监测、预报及预测提供参考依据。The Bay of Bengal （BOB） vortex is objectively defined, then the vortexes generated in seasonal transition period （April--May） of 30 years are statistically investigated, and finally 34 monsoon onset vortexes （MOV） are identified. Further analyses yield the following results. In average state, the MOV is generated ten days before the South China Sea summer monsoon （SCSSM） onset. When there is only one MOV in a year, it is a good indicator to the SCSSM outbreak. When the MOV occurs twice a year, they can also clearly illustrate the disagreement on the onset date of SCSSM caused by interruptions and ambiguous outbreaks. The MOV over BOB can serve as a strong warning signal of SCSSM. It is strongly suggested that this signal be used in monitoring and forecasting the SCS summer monsoon outbreak.

关 键 词：季风爆发性低涡 南海夏季风 季风预警 先兆信号 

分 类 号：P425.42[天文地球—大气科学及气象学]