Abstract: Applying lead/lag correlation analysis on Sea Surface Temperature (SST) in different regions, the main reasons that cause the Western Pacific SST anomaly were investigated. Based on the theories of Pacific-East Asian teleconnection and Indian Ocean capacitor effect, the pointwise maximum correlation of SST anomaly in the Western Pacific with that in the Eastern Pacific and the Tropical Indian Ocean was analyzed, as well as the corresponding lead-lag time (in month). According to the mechanisms mentioned above, the SST variations of the Eastern Pacific or the Tropical Indian Ocean are expected to lead SST variations of Western Pacific by 2?3 months as the response time of ocean is very long. The results show that the SST anomaly in the Western Pacific leads the Eastern Pacific by 1?2 months (under the conditions of both El Nino and La Nina) and leads the Tropical Indian Ocean by 3?4 months. This indicates that neither the Eastern Pacific nor the Indian Ocean is the main reason that causes the SST anomaly of the Western Pacific. The reason that causes SST anomaly of the Western Pacific is very complicated and may be caused by many different factors.

Key words: air-sea interaction, Western Pacific, lead/lag correlation analysis, SST anomaly

摘要： 通过对不同区域海表面温度(SST)资料做超前/滞后相关性分析, 研究导致西太平洋SST异常的主要因素。基于东、西太平洋相互作用理论和印度洋电容器效应理论, 将热带西太平洋SST异常的变化分别与热带东太平洋和印度洋SST异常做超前/滞后相关性分析, 得到每个格点与强迫场之间相关性最显著的月份, 从时间的角度研究西太平洋SST异常变化与东太平洋和印度洋之间的关系。按照上述两种理论, 由于海洋的比热大, 热响应时间较长, 西太平洋SST变化应滞后于东太平洋或印度洋2~3个月。分析结果显示, 在El Nino和La Nina事件下, 西太平洋SST异常变化均超前于东太平洋1~2个月时相关性最显著; 同时, 西太平洋SST异常变化超前于印度洋3~4个月时相关性最显著。 这表明热带东太平洋和印度洋都不是导致西太平洋SST异常变化的主要因素, 西太平洋SST异常可能由多种因素共同作用所导致。

关键词: 海气相互作用, 西太平洋, 超前/滞后相关性分析, 海温异常