Dynamical Link between Typhoon Activity and the PJ Teleconnection Pattern from Early Summer to Autumn as Revealed by the JRA-25 Reanalysis
Dynamical Link between Typhoon Activity and the PJ Teleconnection Pattern from Early Summer to Autumn as Revealed by the JRA-25 Reanalysis
复制标题
DOI：
10.2151/sola.2007-017
复制
发表时间：
2007
期刊：
影响因子：
1.9
通讯作者：
K. Yamada;R. Kawamura
中科院分区：
文献类型：
--
作者：
K. Yamada;R. Kawamura
利用日本长期再分析项目(JRA-25)的资料，研究了太平洋-日本(PJ)型与台风活动之间动力联系的季节相关性。结果表明，7-10月菲律宾以东台风横跨20°N线向北迁移后不久，PJ型趋于盛行。特别是在初夏，亚洲夏季风西风带进入菲律宾海形成的低层西南风急流使台风产生PJ型，而在秋季，高空亚洲急流有助于PJ作为另一种波导的出现。两种不同波导在纬度位置和强度上的季节差异影响了日本附近地区的PJ垂直倾斜结构。事实还证明，即使台风远离日本，它们也有可能通过PJ的主导地位，在雨季间接和远程激活日本各地的静止锋面。
Using the Japanese long-term Re-Analysis project (JRA-25) data, we investigated the seasonal dependence on dynamical links between the Pacific-Japan (PJ) pattern and typhoon activity. It was found that the PJ patterns tend to prevail soon after typhoons to the east of the Philippines migrating northward across the 20°N line during the period from July to October. Especially in early summer the low-level southwesterly jet formed by the penetration of the Asian summer monsoon westerlies into the Philippine Sea enables the typhoons to generate the PJ pattern, whereas in autumn the upper-level Asian jet contributes to the appearance of PJ as an alternative waveguide. The seasonal differences in latitudinal position and strength between the two different waveguides influence the vertical tilt structure of PJ in the vicinity of Japan. It also turns out that even though the typhoons are far away from Japan, they have the potential to indirectly and remotely activate stationary fronts around Japan during the rainy season through the dominance of PJ.