中—β尺度强对流风暴和暴雨数值模拟中的一些问题

本文利用数值模拟方法探讨各环境背景因子对强对流及暴雨系统发生发展所起的作用，分析了暴雨和强对流风暴的形成机制。结果表明：温度场和湿度场的垂直分布，决定着对流是否可以形成；其水平非均匀性只是改变风暴发展强度、生命期以及分裂特性。风场的动力影响对强风暴的移动、分裂及强度特征也十分重要。最后，对第三运动方程做了量纲分析，发现热浮力是对流风暴发展的决定性因素；而热浮力冲量能更细致地反映对流风暴的发展演变特征。

SOME PROBLEMS ABOUT THE NUMERICAL SIMULATION OF MESO-β SCALE STORMS

The background field with which to trigger storms and the developing mechanisms of them that produce rainstorms are discussed in this paper.The results suggest that the temperature and humidity fields are important to create convectivity,and the wind field affects the movement,disintegration and intensity of storms dynamically.Moreover,the vertical distribution of temperature and humidity field affect storms much more than the horizontal one,which can change the intensity,life time and disintegration of them.Finally,the dimensional analysis of the 3 rdmomentum equation is made to indicate that heat buoyancy is the most important factor to trigger storms,and impulse of heat buoyancy can show features of them more perfectly.