大量的实际探测资料证明,冷暖平流常和大尺度的辐合辐散结合在一起。本文用数值模拟方法,分析了这种复合风场的多普勒径向速度特征,同时分析了雨滴下落速度对这些特征的影响,应用数值模拟得到的散度变化图表,从雷达PPI图像中,可以初步定量分析出各高度的辐合(散)值的大小。
Lots of actual detective data prove that cold or thermal advection often overlap with macroscale convergence or divergence, this kind of Doppler radial velocity character of recombination wind field is analyzed by numerical simulating in the paper, meanwhile the influence by raindrop dropping velocity is analyzed as well, the value of convergence or divergence in each latitude can be gotten quantitatively from radar PPI pictures according to these figures of divergence change which get by numerical simulating.