| A three dimensional (3D) cumulus model with electrification and lightning process is used to investigate the differences in electrification and lightning process between different ice crystal nucleation schemes, while an appropriate observation case is selected. Three ice crystal nucleation schemes are adopted in this study, which are the original empirical formula YS scheme and DE scheme and LP scheme associated with aerosols. The present study indicates that the micro-process especially the micro-process of ice crystal and electrification and lightning process of thunderstorm are influenced by different ice crystals nucleation schemes. A more reasonable ice nucleation parameterization scheme, DE scheme, was used to study the sensitivity of the change of aerosol concentration to the lightning behavior of thunderstorm cloud in the further study, and discuss the micro-physical processes of ice crystal, electric characteristics and discharge results under the different aerosol background, thus providing a better background to study the relationship between the macroscopic and microscopic thunderstorm cloud physical characteristics, providing references for further study on the effects of different aerosol types,particle size and so on. The main results are as follows:(1)The parameterization scheme of ice nucleation directly affects the microphysical process of ice crystals, the vertical spatial distribution characteristics of ice crystals in DE scheme and LP scheme are more consistent with the actual observations, value is greater, ice crystals appear in high temperature region while with charges in DE scheme and LP scheme show an obvious polarity reversal phenomenon, which leads to differences in the charge structure among the three schemes. The charge structure is tripolar in DE and LP scheme, which is more consistent with actual observations.(2)The nucleation of ice crystals changes the lightning discharge characteristics by influencing the charge structure of thunderstorm. The charge structure of thunderstorm determines the type of lightning, while the intensity of charge determines the frequency of lightning. The charge structure presents a tripolar in the new two ice nucleation parameterization schemes, lower positive charge shows at the bottom, which promotes the generation of negative ground lightning. The number of ice crystals are greater in the two new schemes, which eventually leads charge structure is also stronger, the lightning activity and the transmission of positive and negative leader segements significantly increase than YS scheme, and negative leader segements appear in the lower height range. Due to the larger area of charge structure distribution,a small amount of lightning triggering in the new scheme appears in a higher position.(3)The change of aerosol concentration mainly affects the specific water content and number concentration of ice crystal particles, which has little effect on the vertical distribution of ice crystals. When the aerosol concentration increases, the specific water content of ice crystals increases, but when the aerosol concentration increased to 2000, the ice water content showed a downward trend; there is a positive correlation between the concentration of ice nuclei and aerosol concentration, which indicates that the ice crystal size is reduced, compared with large ice crystals, small ice crystals can separate more charges and enhance the electrification process.When the aerosol concentration is further increased, the average mixing ratio of ice crystals remains stable, and the difference between the non-inductive electric rates is not significant. When the aerosol concentration increased to 10000, the lightning frequency in thunderstorm will be relatively reduced, the relative effect of higher concentration of aerosol on ice particles concentration is relatively small because of the competition of cloud water, and ice formation is restricted. |
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