中文摘要：

在三维强风暴动力—电耦合数值模式中引入基于Saunders et al.（1991）实验结果的非感应起电参数化方案S91,在此基础上,利用云水饱和度替代环境温度和有效液水含量将S91方案变形。对比分析一次雷暴单体首次放电前,变形后的S91方案和原S91方案模拟得到的非感应转移电荷的极性、量级、电荷结构以及与霰和冰晶粒子分布之间的关系。结果表明,虽然两种方案采用的电荷密度变化率以及每次碰撞平均转移的电荷量均相同,但不同方案中决定粒子间电荷转移的因子不同对电荷的分布存在较大的影响。加入云水饱和度的S91方案,非感应转移电荷的极性多为正极性,电荷结构先呈单极性后转变为三极性,并有进一步转变为偶极性的趋势。但这两种方案模拟得到的霰与冰晶粒子电荷分布的重合区的范围、大小均不同,这也是造成两种方案电荷结构和转移电荷分布不同的主要原因。

英文摘要：

In order to study the effect of cloud saturation on thunderstorm electrification, a parameterization of non-inductive graupel-ice charge separation S91 based on the laboratory results of Saunders et al. （1991） is introduced into a three-dimensional dynamic-electrification coupled model. The effective liquid water content and environment temperature in S91 are replaced by cloud saturation, resulting in the deformation of S91.The evolution characteristics of non-inductive charge separation polarity, magnitude, charge structure and their relationship with ice crystal and graupel particle distributions produced by the deformation of S91 and original S91 in a typical storm before the first discharge are analyzed,respectively. The results indicate that the transfer charges per collision and the change rates of charge density adopted in these two parameters are the same, but difference of factors which determine the increase of graupel and ice particles in these schemes exerts a relatively important influence on the distribution of charge.In the deformation of S91 scheme, the domain polarity of non-inductive charge separation changes is basically positive, the charge structure switches from unipolar to tripole, and it tends to produce a positive dipole charge structure. In addition, the difference of charge distribution and charge separation changes in the schemes are caused by the difference of coincidence region between graupel and ice particles.