摘要
利用美国联合台风警报中心JTWC发布的自1972年以来的北印度洋风暴数据,美国国家环境预测中心和国家大气研究中心NCEP/NCAR逐月再分析资料和日本气象厅JMA月平均海表面温度SST资料,分析了初夏4、5月孟加拉湾风暴活动与前期印度洋海温的关系。结果表明:4、5月孟加拉湾TS活动与前期1-3月澳大利亚以西海域海温呈显著的负相关,即冬末春初海温偏高时,4、5月孟加拉湾(简称孟湾,下同)TS爆发偏少、爆发时间偏晚或者不发生;而关键区海温偏低时,如果30°S以北的印度洋海温稍偏冷(暖),而西南印度洋和东南印度洋海温则稍偏暖(冷),则初夏孟湾TS不爆发(多发、早发)。进一步分析显示由东南印度洋海温偏高(低),引起的局地环流变化导致了马斯克林高压偏弱(强),从而引起东半球越赤道气流偏弱(强),是初夏孟湾TS爆发晚(早)、不(多)发生的可能的主要原因。而且,当索马里越赤道气流和新几内亚越赤道气流存在弱的反位相协同变化时,对孟湾TS有较好的指示意义。
In this study,using the northern Indian Ocean storms data collected since 1972 and released by JTWC,along with NCEP/NCAR monthly reanalysis data and JMA mean monthly SST data,we analyzed the relationship between the early summer storm activity in the Bay of Bengal and the previous Indian Ocean SST.The results showthat the TS activity in April and May of the Bay of Bengal and the SST of the Indian Ocean to the west of Australia have a significant negative correlation,namely the outbreak time of TS in the Bay of Bengal is late or the TS does not occur when the SST in the key areas is high.In addition,when the SST of the important areas is low,there are two scenarios for storm activity.If the Indian Ocean SST north of 30°S is slightly cold( warm) and that of the southeast and southwest Indian Ocean is slightly warm( cold),then the early summer TS appears less frequently or not at all( multiple and early).Further analysis shows that the local circulation changes caused by the high( low) SST in the key area,i. e. the Indian Ocean,leads to the weak( strong) Maschlin high and weak( strong) transequatorial current in the Eastern Hemisphere,which are likely the main reasons for the occurrence time of TS being late( early) and the TS frequency being lower( higher) in early summer.Moreover,when the Somali-equatorial flowand the NewGuinea-equatorial airflowundergo weak antipodean synergistic changes,there is a better indication of TS in the Bay of Bengal.
作者
金燕
晏红明
万云霞
马永林
JIN Yan;YAN Hongming;WAN Yunxia;MA Yonglin(Yunnan Climate Centre,Kunming 650032,China;Yunnan Meteorological Service Centre,Kunming 650032,China;Chuxiong Meteorological Bureau of Yunnan,Chuxiong 675000,China)
出处
《大气科学学报》
CSCD
北大核心
2020年第2期358-369,共12页
Transactions of Atmospheric Sciences
基金
国家自然科学基金资助项目(41575097)
云南省自然科学基金重点项目(2016FA041)
2017年云南省气象事业发展“十三五”规划重点工程建设项目。
关键词
孟湾TS
印度洋海温
马斯克林高压
越赤道气流
Bay of Bengal storm
Indian Ocean SST
Maschlin high
transequatorial current
