Numerical simulation of the effect of microphysical process of thunderstorm on its electrical activity

In this paper, the one-dimensional time-varying model of thundercloud electrification has been used for simulating two thunderstorm processes by using observations of CCOPE and STEPS primarily, and discussing the effect of surface temperature and reversal temperature on electrical process of thundercloud from sensitivity tests. In the model, Fletcher glaciation mechanism and Hallett-Mossop glaciation mechanism have been adopted as the ice glaciation mechanisms of crystal. The numerical simulation results show that, the site of the vertical field extremes in the results simulated by using radiosonde observation data of STEPS has good consistency with surveyed results, but the simulated extremes are larger than surveyed extremes. Sensitivity tests results show that, with surface temperature increasing, the vertical thickness of negative charge will be decreased; the biggest density of positive charge and negative charge will be increased. When surface temperature is 32°C and the reversal temperature is lower than -26°C, there will be a reversed-polarity charge structure in thundercloud.