摘要:为了探讨对流强度大小对雷暴云内微物理发展和起电过程的影响，基于已有的二维积云起、放电模式，改变其扰动温度进行敏感性试验。试验结果表明：对流强度对雷暴云内微物理过程、起电率及后续电荷结构的产生均有一定程度的影响：1）对流强度较小时，冰晶粒子极大值在高温区（高于-13.8℃）出现，对流强度较大时，上升风明显增强，将更多的水汽带入高空，气溶胶活化过程明显增强，使得云滴粒子明显增多，冰晶粒子较早产生，冰晶粒子极大值在低温区（低于-13.8℃）出现，发展过程更为剧烈；同时，较高的对流强度也使得降雨量增多，霰粒子数目也在对流发展旺盛时期显著增多。2）非感应起电率主要和冰晶-霰的碰并分离过程有关，对流强度较大时，非感应起电率较大，电荷结构持续时间较长，过程明显，感应起电率也较强。3）对流强度较大时，电荷结构更为复杂，雷暴云发展初期基本呈现为三极性，发展旺盛时期底部正电荷区域嵌入一个较小的负电荷区，呈现四极性电荷结构，雷暴云发展末期基本呈现偶极性电荷结构；对流强度较小时，发展初期、旺盛时期均呈现三极性电荷结构，发展末期呈现偶极性电荷结构。
关键词:对流强度/
扰动温度/
雷暴云/
非感应起电率
Abstract:In order to investigate the effect of different convective intensity on the microphysical development and electrification process of thunderstorm cloud, sensitivity experiments based on the existing two-dimensional convective cloud and discharge mode have been carried out with various disturbance temperatures. The results show that convective intensity has influences on the microphysical development characteristics, electrification rate and charge structure of the thunderstorm cloud. (1) When the convective intensity is small, the maximum value of ice crystals is located in high temperature region (above -13.8℃); when the convective intensity is large, ascending motion obviously enhances, and more water vapor is brought to upper levels. Meanwhile, the aerosol activation process significantly intensifies, the number of cloud droplets obviously increases and ice crystal particles are produced earlier and the maximum value of ice crystals is located at low temperature region (below the -13.8℃), and the development process is more intense. At the same time, the stronger the convective intensity is, the more the rainfall would be. Besides, the number of graupel particles also increases during the convection development period. (2) The non-inductive charging rate is mainly related to the collision and separation process of ice crystals and graupels. When the convective intensity is large, the non-inductive charging rate is also large, and the polarity reversal duration is obvious. This is also the case for inductive charging rate. (3) When the convective intensity is large, more complicated charge structure appears. The charge structure is tripolar during the earlier stage of the lifespan of the thunderstorm, but a smaller negative charge region is embedded during the later stage of the lifespan of the thunderstorm. When the convective intensity is small, the tripolar charge structure presents during the early stage of the thunderstorm, and the dipolar charge structure appears in the dissipating period of the thunderstorm.
Key words:Convective intensity/
Disturbance temperature/
Thundercloud/
Non-inductive charging rate
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