厄尔尼诺和反厄尔尼诺事件与西北太平洋台风活动

TYPHOON ACTIVITY IN THE NORTHWEST PACIFIC IN RELATION TO EL NINO/ LA NINA EVENTS

关键词:  台风  厄尔尼诺和反厄尔尼诺  奇异值分解

Key words:  Typhoon  El Nino and La Nina  SVD

摘要:

用统计相关和典型年合成方法分析了厄尔尼诺和反厄尔尼诺事件与西北太平洋台风活动的关系,指出厄尔尼诺年台风活动减少,反厄尔尼诺年台风活动增加,而且台风活动与厄尔尼诺、反厄尔尼诺事件起始和终止时间、强度、台风生成区域有关。利用厄尔尼诺和反厄尔尼诺年台风活动频数的统计特征,及台风频数与海温等要素的时滞相关关系,为台风频数的预测提供了有益的信息。还应用奇异值分解方法,分析了高度场和海温场的相关关系。结果表明,厄尔尼诺年海气耦合作用将造成不利于台风发展的环流条件,因此台风偏少,反厄尔尼诺年则出现相反的情况。

Abstract:

The relationship between typhoon activity in the northwest Pacific and El Nino and La Nina events is analyzed with statistical and composition methods. It is indicated that there are fewer frequent typhoon activities in El Nino years but more frequent typhoon activities in La Nina years. The start and end time and intensity of El Nino and La Nina events also have influence on typhoon formation. The typhoon activity statistical characteristics supply information that might be used in seasonal prediction. Using singular value disassemble(SVD)method, the relationship between 500hPa height and SST fields is also analyzed. The result shows that the sea-air-coupling interaction in El Nino and La Nina years causes abnormal frequency of typhoon activities.