广义非线性亚临界湿对称不稳定
    点此下载全文
引用本文:
摘要点击次数: 1261
全文下载次数: 975
作者单位
李艳杰 陆维松邵海燕陶丽  
基金项目:国家自然科学基金资助项目(40275016);国家教育部“高等学校博士学科点专项科研基金”项目
中文摘要:从含摩擦耗散与凝结潜热的〖WTB1X〗f〖WTB1〗平面Boussinesq近似下的非线性扰动方程组出发,得到了湿空气中的广义能量方程,推导出非线性亚临界湿对称不稳定的必要条件,并将不稳定判据与干空气情况相比较,首先解析地分析得到凝结加热反馈机制对亚临界对称不稳定的影响。其次针对中尺度大气层结不稳定和稳定的情况,分别计算出初始扰动振幅的临界值,结果表明,相对干空气而言,饱和湿空气情况下,当中尺度大气层结不稳定时,亚临界对称不稳定更容易发生,即使中尺度大气层结稳定,亚临界对称不稳定也容易发生。这一结果改进了干空气下的非线性亚临界对称不稳定理论。
中文关键词:亚临界  湿对称不稳定  非线性  凝结加热
 
Generalized nonlinear subcritical moist symmetric instability
Abstract:Starting from nonlinear equations on the 〖WTB1X〗f〖WTB1〗 plane containing frictional dissipation and condensation heating under the Boussinesq approximation,the equation of generalized energy in moist air is presented,and the necessary condition of subcritical moist symmetric instability is derived.The influence of condensation heating on the subcritical symmetric instability is derived analytically at first.Then the critical values of the initial disturbance amplitude are calculated in the cases of unstable and stable meso scale atmosphere stratification.It is found that subcritical symmetric instability is easier to happen in moist saturated air with either the unstable or stable stratification than in the dry air,and easier with the unstable than stable stratification.The results improve the theory of nonlinear subcritical symmetric instability in the dry air.
keywords:subcritical moist symmetric instability  nonlinearity  condensation heating
查看全文  查看/发表评论  下载PDF阅读器