最优化方法在确定对流混合层顶夹卷率中的应用  

Application of the Optimization Arithmetic to Ascertain the Entrainment Velocity in the Top of the Well-Mixed Layer

作　　者：卢萍[1] 郑琴[1] 宇如聪[1] 穆穆[1] 

机构地区：[1]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029

出　　处：《大气科学》2004年第1期112-124,共13页Chinese Journal of Atmospheric Sciences

基　　金：中国科学院创新项目KZCX2 2 0 8;"十五"攻关项目 2 0 0 1BA60 7B;国家自然科学基金资助项目 40 2 3 3 0 3 1资助

摘　　要：晴天充分混合的对流边界层 (CBL)中常采用相对简单的零阶近似平板模式。在该模式中 ,通常假设边界层顶的夹卷通量与地面通量有着固定的线性关系作为其闭合条件 ,即 (wθ) h=-A (wθ) s。由于受观测资料的限制 ,参数A通常是由大涡模拟 (LES)的方法得到 ,并利用有限的观测资料加以验证。作者基于ARM (AtmosphericRadiationMeasure mentProgram)观测资料 ,利用最优化参数算法 ,确定该闭合参数 ,使得对流混合层模式能最大可能地再现实际边界层的发展过程。首次尝试了最优参数算法在确定真实物理过程参数中的应用。模拟结果分析表明 ,在观测资料足够多的情况下 。A simple zero-order flat model is usually used to characterize the well-mixed convective boundary layer under clear sky. In this model, we often hypothesize the closed-condition as the entrainment flux in the top of the atmosphere boundary layer has the fixed linear relationship to the surface heat flux, that is( (wθ) h=-A (wθ) s). Due to the limited observation data, the parameter A is always obtained from the large eddy simulation, then the limited observation data is utilized to confirm it again. In this study, based on the ARM data the optimization arithmetic is used to ascertain the closed-parameter, so that the convective mixed layer model can reappear the actual boundary layer’s developing process. This study tries to apply the optimization arithmetic to ascertain the factual physical process parameter. The results suggest that, if the data is enough, the optimization arithmetic should be an effective approach to ascertain the closed-parameter.

关 键 词：对流混合层 夹卷率 最优化算法 大涡模拟 闭合参数 

分 类 号：P4[天文地球—大气科学及气象学]