摘要
本文利用包含海洋表面边界层、线性海洋大气动力学以及完整的关于不均匀气候态线性化ＳＳＴ预报方程的热带太平洋海气耦合模式，在真实的气候背景态和参数域内，研究了海气耦合系统的特征值问题，确定了线性耦合系统主模的特征周期及其稳定性特征，进而揭示了主模和ＥＮＳＯ的关系。结果表明：准两年振荡是线性海气耦合系统中的最不稳定模态，且只有该模态类似于ＥＮＳＯ水平结构。因此，准两年振荡很可能是海气耦合系统固有的最根本性的振荡过程。本文也对准两年振荡的形成与年循环的关系以及它在ＥＮＳＯ时间尺度形成中的作用进行了讨论。
By using a tropical Pacific coupled air-sea model with an oceanic surface boundary layer,including the linear atmospheric and oceanic dynamics and linearized SST prognostic equation about non-uniform climatic states, the characteristic period and stability of principal modes in the linear coupled air-sea system and their association with ENSO are investigated by solving the eigenvalue problem within realistic ranges of climate background states and parameters. Results show that the quasi biennial (QB) oscillation is the most unstable mode of the linear coupled air sea system and only the QB mode displays ENSO-like horizontal structure. Therefore, as an intrinsic mode of coupled air-sea system, the QB mode would be fundamental for full understanding of mechanism responsible for ENSO cycle. Moreover, the relationship between the QB mode and the mean annual cycle, and the influence of the QB mode in determining the time scales of ENSO variability are also discussed in this paper.
出处
《大气科学》
CSCD
北大核心
1996年第5期547-555,共9页
Chinese Journal of Atmospheric Sciences
基金
国家攀登计划项目
国家自然科学基金
