西太平洋副热带高压（简称副高）是影响夏季东亚地区天气气候和我国天气变化的重要系统。副高变异的动力学机理一直是气象科学研究和灾害性天气研究的难点问题，具有重要的科学意义和应用价值。基于实际副高异常活动的多样化、复杂性天气事实，针对不同时间尺度的副高动力系统之间相互影响和反馈机制尚未彻底弄清的科学问题，在对副高系统的动力相关因子合理诊断判别的基础上，通过引入改进的相空间重构方法和动力系统多层次耦合思想，将不同时间尺度的副高动力系统耦合起来，构建副高多层次关联的非线性动力系统，揭示不同层次之间的能量交换和串级输运及其对副高系统活动和变异的动力特性影响和非平稳行为制约。通过本项目研究，构建副高多层次耦合系统、揭示副高系统新的现象特征、探索副高活动与变异机理的新思路、新方法，为进一步深入弄清副高的结构、演变与活动规律和内在机理提供理论依据和科学解译。

The West Pacific subtropical high (WPSH) is an important system which has a great impact on summer climate change in East Asia, especially in our country. The dynamical mechanism of WPSH variation is a difficult problem in the research of meteorological science and disaster weather, which has important scientific significance and application value. Based on the diversification and complexity of the actual WPSH abnormal activities, Aiming to tackle the unsolved scientific problems such as the interaction and feedback mechanism among the different time scales of WPSH dynamical system, we diagnose and discriminate the reasonable factors of the WPSH dynamical system. Then we introduce the improved phase space reconstruction method and multi-level coupling thought of the dynamical system to couple the different time scales of WPSH dynamical system. The multilevel nonlinear dynamical systems of WPSH can be established, which can reveal the dynamical characteristics influence and non-stationary behavior constraints of the energy exchange among different levels and cascade transport to the multi-level WPSH system. Through this project, the multi-level coupling system of WPSH can be constructed and the new features of WPSH system can be revealed, which explore the new ideas and new methods of WPSH activity and variation mechanism. Our study will provide theoretical basis and scientific interpretation for the further understanding of structure, evolution, activity regularity and internal mechanism of the WPSH.