上升气流对雷暴云中电荷结构复杂程度影响的模拟  

Simulation on Effect of Updrafts on Complexity of Charge Structures in Thunderstorm Clouds

作　　者：吴泽怡 郭凤霞[1] 鲁鲜 刘舟 邓洁 陈可[1] 王清源 WU Zeyi;GUO Fengxia;LU Xian;LIU Zhou;DENG Jie;CHEN Ke;WANG Qingyuan(Emergency Management College/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD),Nanjing University of Information Science and Technology,Nanjing 210044)

机构地区：[1]南京信息工程大学应急管理学院/气象灾害预报预警与评估协同创新中心,南京210044

出　　处：《大气科学》2025年第1期153-172,共20页Chinese Journal of Atmospheric Sciences

基　　金：国家重点研发计划项目2017YFC1501503;国家自然科学基金项目41975003;第二次青藏高原综合科学考察研究项目2019QZKK0104。

摘　　要：为了进一步认识上升气流对雷暴云内复杂电荷结构特征的影响,利用加入起放电参数化方案的WRF模式对DC3试验中2012年6月6日一次出现反极性电荷结构的强雷暴过程进行模拟。结果表明,起电区对应强回波区,主要发生在上升气流区中心云水混合比大于0.2 g kg^(-1)的冰水混合区,非感应起电机制主导着雷暴云内的起电过程。上升气流区外围区域存在可观的电荷,主要是由气流将起电区域的荷电粒子向后水平输送形成的。同类粒子带电极性在较大范围内变化少,但由于各类粒子的含量和荷电量不同,导致净电荷密度分布呈现较复杂的结构。达到一定强度的上升气流可以破坏电荷区的连续性,导致对流区出现高密度的、正负极性交错分布的、范围更小的电荷区。层云区由于没有上升气流,荷电粒子主要源自上升气流区的水平输送,所以其电荷区分布较连续且范围较大,但电荷密度相对弱。处于不同生命期的单体由于上升气流强度和倾斜程度不同,单体间的水成物粒子分布特征会存在一定差异,使得反转温度和起电率出现较大不同,因此单体合并时上升气流区之间的电荷区更破碎,电荷结构更复杂。Aiming at further comprehending the effect of updrafts on the complex charge structure characteristics in thunderstorm clouds,the WRF(Weather Research and Forecasting)model with an electrification and discharge parameterization scheme is employed to simulate the process of a strong thunderstorm with an inverted charge structure that was reported on 6 June 2012,in the Deep Convective Clouds and Chemistry(DC3)experiment.The results demonstrate that the electrification region corresponds to the strong echo region,which mainly occurs in the ice-water mixing region with cloud water mixing ratios exceeding 0.2 g kg^(-1)in the updraft region.The noninductive electrification mechanism dominates the electrification process in thunderstorm clouds.There is a considerable amount of charged particles in the periphery area of the updraft,which is mainly formed by airflow-induced backward horizontal transport of charged particles from the electrified area.The polarity of homogeneous particles slightly changes in a large range,but the net charge distribution becomes more complex because of the different contents and charges of the particles.An updraft with a certain intensity can destroy the continuity of the electrified area,resulting in a high-density,smaller area with positive and negative staggered distribution in the convection region.Because there is no updraft in the stratiform area,the charged particles in this area mainly originate from the horizontal transport in the updraft region;therefore,in the stratiform cloud area,the charge structure is relatively continuous and wide,but the charge density is relatively weak.Because of the different intensities and inclination degrees of updraft in different cell life periods,there exist certain differences in the distribution of hydrometeor particles between cells,making the reversal temperature and electrification rate of the particles notably different from each other.Therefore,during cell merging,the electrified area in the updraft region becomes more fragmented,and the char

关 键 词：雷暴 电荷结构 水成物粒子 起电 上升气流 

分 类 号：P446[天文地球—大气科学及气象学]