Lightning activity and its associations with cloud structures in a rainstorm dominated by warm precipitation

It is the data associated with the figures in the paper titiled " Lightning activity and its associations with cloud structures in a rainstorm dominated by warm precipitation " which is being in the process of submission. The following is the abstract of this paper. Lightning activity and its associations with cloud structures during a rainstorm dominated by warm cloud precipitation were studied in Guangdong, China on May 7, 2017, using three-dimensional lightning location and polarimetric radar data. The overall convection and lightning activities of the rainstorm were weak. The rainstorm generally showed a typical tripolar charge structure with the main negative charge core located between the −15 and −8 °C environmental isotherms in the first 4 h. The height of the charge regions clearly decreased after this period, with the main negative charge core being below the –8 °C isotherm. Lightning discharges were more concentrated in areas featuring relatively weak convection and relatively low precipitation intensity. Most of the locations with lightning discharges were dominated by dry aggregated snow and weak updrafts and downdrafts. This investigation demonstrated that the lightning discharges were spatially separated from the area of origin of charging in this rainstorm. It is proposed that, with weak convection in the rainstorm, the charging rate was lower than the speed of charge transfer from the area of origin, causing a relatively low charge density and a low frequency of lightning in the area of origin of charging. Meanwhile, the aggregation of small charged particles in regions away from the area of origin of charging might be conducive to the formation of a relatively high charge density and therefore relatively frequent lightning flashes. This situation is different from a typical thunderstorm with strong convection.本数据集与已投稿的题为《暖降水主导暴雨中的闪电活动及其与云结构的关联》的论文配图数据相关。以下为该论文的摘要：2017年5月7日，研究团队基于三维闪电定位（three-dimensional lightning location）与偏振雷达（polarimetric radar）观测资料，针对中国广东地区一次暖云降水主导的暴雨过程，开展了闪电活动及其与云结构之间关联的研究。本次暴雨的整体对流活动与闪电活动均较弱。暴雨发生的前4小时内，整体呈现典型的三极性电荷结构，主负电荷核心位于环境温度-15℃至-8℃的等温层之间；此后，电荷区高度显著降低，主负电荷核心下移至-8℃等温层以下。闪电放电多集中于对流相对偏弱、降水强度相对较低的区域。多数闪电发生区域以干聚合雪粒子为主，且伴随弱的上升气流与下沉气流。本研究表明，本次暴雨中的闪电放电与电荷起源区域在空间上相互分离。研究提出，由于本次暴雨对流活动较弱，电荷生成速率低于电荷从起源区域向外传输的速率，导致电荷起源区域内电荷密度相对偏低，闪电发生频次偏少；与此同时，远离电荷起源区域的带电小粒子聚合过程，可能有利于形成较高的电荷密度，进而催生更为频繁的闪电活动。这一特征与典型强对流雷暴存在显著差异。