基于副热带高压异常活动个例的动力模型重构与变异特性剖析  

Dynamic Model Reconstruction and Corresponding Abnormal Characteristics Anatomy of Subtropical High based on Actual Data Time Series Samples

作　　者：张韧[1] 洪梅[1] 刘科峰[1] 朱伟军[2] 

机构地区：[1]解放军理工大学气象海洋学院,江苏南京211101 [2]南京信息工程大学,江苏南京210044

出　　处：《地球科学进展》2014年第11期1250-1261,共12页Advances in Earth Science

基　　金：国家行业科研专项"北半球冬季风暴轴变异及其对我国冷空气活动的影响"(编号:GYHY201306028);国家自然科学基金项目"西太平洋副热带高压季节内活动与变异的案例剖析与机理分析"(编号:41075045)资助

摘　　要：针对1998年夏季造成我国严重洪涝灾害的副热带高压异常活动,基于动力系统重构思想和遗传算法,从1998年观测资料时间序列中反演重构了副热带高压活动的非线性动力模型,并结合天气实况进行了副热带高压活动变异的动力特性分析。结果表明,针对副热带高压异常个例实际观测资料反演重构的副热带高压活动的非线性动力模型,可客观描述副热带高压活动(特别是异常活动)特征并予以合理的机理解释。进一步的分析讨论表明,随着强迫参数的逐渐增加,副热带高压动力系统将会发生平衡态的分岔、突变,平衡态的上述变化与实际天气过程中的副热带高压北跳、南落以及副热带高压双脊线现象有很好的对应关联,并可对其进行合理的机理解释,进而为副热带高压等难以准确构建解析模型的复杂天气系统的机理分析和动力特性讨论提供参考。Aiming at the abnormal activity of West Pacific Subtropical High （WPSH） inducing the serious flood disaster in 1998, and considering the complex seasonal activity of WPSH in summer, based on the actual geo- potential height field time series observational data in 1998, a non-linear dynamic model of WPSH was reconstruc- ted by using the idea of dynamic system retrieval and genetic algorithms. Combined with the synchronous actual weather process, the corresponding dynamic characteristics and variation mechanism of WPSH, such as the equilib- rium state destabilization and bifurcation of the WPSH system, were analysed and discussed. The research showed that due to the advantages of global optimization and parallel calculation of GA, a nonlinear dynamic model could be reasonably and quickly reconstructed, and the reconstructed nonlinear dynamic model of WPSH derived from the actual abnormal case data could be used for describing objectively and explaining reasonably the basic characteris- tics and the abnormal activity process of WPSH. The dynamic discussion showed that the configuration and diversi- fication of WPSH system equilibriums, such as bifurcation, catastrophe had a good matching with the actual medium- short period abnormal activity of WPSH, such as northward jumping and southward droping, as well as double-ridge line pattern. The modality of WPSH geopotential height field induced by multi-equilibriums destabilization was more complex than that of by single-equilibriums bifurcation, and their exhibition patterns were more different. With the forcing parameters increaseing, closing with and exceeding critical value, the WPSH system equilibrium state desta- bilization or bifurcation would occur. Especially, when the equilibrium state jump/drop from low/high to the high/ low value, corresponding WPSH system behaved as a leap northward/fall southward, moreover, when the stable e- quilibriums state from 1 to 2, corresponds with the pattern of ＂double-ridges＂ phenomenon of WPSH, contrariwise, ＂double-ri

关 键 词：副热带高压 遗传算法 动力模型重构 分岔突变 

分 类 号：P433[天文地球—大气科学及气象学]