基于副高-季风非线性动力模型的动力特性讨论与机理分析  

DYNAMIC CHARACTERISTICS AND MECHANISMS OF A NONLINEAR DYNAMIC MODEL FOR THE SUBTROPICAL HIGH-MONSOONS: DISCUSSIONS AND ANALYSIS

作　　者：余丹丹[1] 张韧[2] 洪梅[2] 程亮[1] 

机构地区：[1]中国人民解放军61741部队 [2]解放军理工大学气象学院

出　　处：《热带气象学报》2010年第4期429-437,共9页Journal of Tropical Meteorology

基　　金：江苏省气象灾害重点实验室开放课题(KLME0507);热带海洋气象科学基金(200609);国家自然科学基金资助项目(40375019)共同资助

摘　　要：基于NCEP/NCAR再分析资料,依据动力系统反演思想,采用遗传算法从1998年实际观测资料中,客观合理地反演重构了副高特征指数与东亚夏季风因子的非线性动力模型,并结合1998年天气实况,讨论了模型中外参数的变化对副高系统平衡态失稳和分岔的影响。从而为副高等难以准确构建动力模型的复杂天气系统的物理机理分析和动力行为讨论,提供了有益的研究思想和方法手段。研究发现,副高指数平衡态的分布和变化与实际副高的中短期异常活动相对应,副高系统由高值稳定平衡态向低值稳定平衡态跳跃的突变行为对应副高的异常南落过程,副高系统由双稳定平衡态向单稳定平衡态并入的分岔行为对应副高"双脊线"并存到消失的过程。Based on the NCEP/NCAR reanalysis data and following the idea of retrieval from dynamic systems and the genetic algorithm, a non-linear dynamic model for the subtropical high indices and the East Asian summer monsoon factors is retrieved and reconstructed objectively and correctly from the actual observations of 1998. Then, with the weather facts of that year, the impacts of changes in model parameters are also discussed on the loss of equilibrium of the subtropical high and its bifurcation so as to provide constructive research ideas, methods and means for the discussion of physical mechanisms and dynamic behaviors of such complex synoptic systems as the subtropical high, for which it is usually difficult to establish correct dynamic models. It is found that the distribution and change of the equilibrium corresponds with the actual medium-and short-term abnormal activity of the subtropical high; the abrupt change in the stable balance state from high values to low values is corresponding to the process of ＂abnormal southward advancement＂ of the subtropical high, while the bifurcation from the dual high-value stability to dual low-value equilibrium of the subtropical high is corresponding to the existence and disappearance of ＂double ridge lines＂ of the subtropical high.

关 键 词：天气学 非线性动力模型 遗传算法 副热带高压 

分 类 号：P434.5[天文地球—大气科学及气象学]