非地转湿Q矢量的改进及其应用

在完全考虑非绝热加热项作用的前提下,从原始方程出发,推导出改进后的非地转湿Q矢量(Q^q),以及用其散度作强迫项的ω方程,将其应用于一次梅雨锋暴雨诊断分析,结果表明:改进后的非地转湿Q矢量对同时刻地面降水的反映能力较岳彩军改进的湿Q矢量(Q^M)、原非地转湿Q矢量(Q^*)、非地转Q矢量(Q#)有显著的提高;在整个梅雨锋暴雨过程中,500hPa高度上的Q^q矢量散度辐合场的辐合强度及其辐合中心位置对同时刻的降水强度及雨区位置有非常好的指示作用;Q^q矢量的垂直分布揭示了次级环流的方向和强弱,暴雨位于次级环流的上升支附近。

Improvement and Application of Ageostrophic Wet QVector

With diabatic heating completely considered and based on a primitive equation,derived are an expression of modified ageostrophic wet Q-vector(Q^q) and the ageostrophic ω equation with the Q^q divergence as a forcing term.The modified ageostrophic wet Q-vector is then applied to diagnoses a heavy rain event.The results show that:the ability of simultaneously reflecting precipitation of Q^q is enhanced significantly in contrast to Yue Caijun''s modified wet Q-vector(QM),original ageostrophic wet Qvector(Q^*) and ageostrophic Q-vector(Q^#);throughout the Meiyu front rainstorm process,the convergence intensity and center of 500 hPa Q^q divergence field are good indicators for the intensity and location of precipitation;and the vertical distribution of Q^q reveals the direction and intensity of the secondary circulation,and the heavy rain may occur around the uprising leg of the secondary circulation.