强对流降水过程动力因子分析和预报研究

利用对流涡度矢量垂直分量,湿热力平流参数和波作用密度等动力因子对2009年7月8日发生在我国华北南部地区的强对流降水过程进行诊断分析,结果表明,这些动力因子能够综合描述降水系统水平风场垂直切变,涡度扰动以及位温平流和广义位温(及其扰动)的经向梯度等动力学和热力学特征,在降水区对流层中低层表现为强信号,在非降水区表现为弱信号.利用美国NCEP/NCAR 0.5度GFS的6 h,12 h,18 h和24 h预报资料计算分析2009年6月2日至10月1日动力因子对观测降水的指示预测作用,结果表明,动力因子对观测 关键词： 对流涡度矢量垂直分量 湿热力平流参数 波作用密度

Analysis and forecasting of heavy-rainfall event by strong convection

For the case of severe convection occurring in the southern region of North China on July 8, 2009, the three dynamical factors, namely, vertical component of convective vorticity vector, moist thermodynamic advection parameter and wave-activity density are diagnosed. The result shows that the anomalous-value regions of dynamical factors are located mainly in middle and lower troposphere over the strong precipitation area. Since the dynamical factors can effectively describe the synthetical characteristics o...