摘要
基于欧洲中期天气预报中心（ＥＣＭＷＦ）的资料（１９８１—１９８８），本文对全球热带大气中的１０—２０天（准双周）振荡进行了比较系统的研究，包括其动能的分布及演变。扰动的结构和传播特征等。资料分析充分表明，热带大气１０—２０天振荡是热带大气中另一重要低频系统，其动能比３０—６０天振荡还要大，而其结构和活动又同３０—６０天振荡很不一样。例如热带大气１０—２０天振荡主要表现为纬向波数２—４；垂直结构以正压特征更显著；主要表现为向西传播；其经向风分量与纬向风分量同等重要。因此，对热带大气１０—２０天振荡值得更多注意。
Based on the 10-20 day band-pass filtered data which are computed from ECMWF global dais (1981-1987), the 10-20 day (quasi-two-week) atmospheric oscillation in the tropics is studied systematically in this paper. The oscillation includes that in the distribution and evolution of kinetic energy,the structure and propagation feature of this kind of low-frequency and so on. It is shown that the 10-20 day osCillation is another important low-frequency system in the tropical atthosphere. Its kinetic energy is even stronger than 30-60 day oscillation. Its structllre and activity is different from the 30-60day oscillation. For instance, the 10-20 day oscillation in the tropical atmosphere is dominated by the perturbances of the zonal wavenumber 2-4. Its vertical structure mainly displays barotropic feature. It mainly propagates westwards. The meridional wind component and zonal wind component are same important. Therefore, the study focused on the 10-20 day oscillation in the tropical atmoSPhere is very necessary.
出处
《大气科学》
CSCD
北大核心
1995年第4期435-444,共10页
Chinese Journal of Atmospheric Sciences
关键词
热带
准双周振荡
大气
低频振荡
tropical atmosphere
quasi-tWo-week (10-20 day) oscillation
low-frequency system.
