中国气象科学院恶劣天气国家重点实验室郑栋团队揭示了负触发闪电雷暴的结构特征。相关论文于2025年3月6日发表在《大气科学进展》杂志上。

研究组利用三维闪电定位系统、极化雷达和触发闪电（TLF）通道的电流测量数据，分析了华南地区与负TLF相关的母雷暴的结构特征。触发闪光区（TFR）显示出明显的层状云特征，包括较低的雷达反射率高度和0°C以上冰晶和干雪的优势。

相比之下，雷暴对流核心区（CCR）在混合相层中往往有更多的霰颗粒，其冰水含量峰值约为TFR的3.4倍。TFR中放电所涉及的电荷区呈现出偶极电荷结构，-5°C层大致划分了上部的正电荷区和下部的负电荷区。相反，CCR具有典型的三极电荷结构。

TFR中的主导偶极电荷结构导致负电荷区下方的负电荷场随高度增加，为成功触发负TLF提供了必要条件。此外，TLF的水平范围与其持续时间和电荷转移呈正相关。与电荷转移较小的TLF区域相比，电荷转移较大的TLF通道传播的区域往往具有更大的最大雷达反射率，但平均雷达反射率较低。

附：英文原文

Title: Structural Characteristics of Thunderstorms Associated with Negative Triggered Lightning Flashes

Author: Xiaojie Liu, Dong Zheng, Yijun ZHANG, Weitao LYU, zhang yang, Yanfeng Fan, Hai Yu

Issue&Volume: 2025-03-06

Abstract: This study utilizes data from a 3-D lightning location system, polarimetric radar, and current measurements from channels of triggered lightning flashes (TLFs) to analyze the structural characteristics of the parent thunderstorms associated with negative TLFs in South China. The triggered-flash region (TFR) displays distinct stratiform cloud characteristics, including lower radar reflectivity heights and a predominance of ice crystals and dry snow above the 0°C layer. In contrast, the thunderstorm convection core region (CCR) tends to have more graupel particles in the mixed-phase layers and exhibit an ice-water content peak approximately 3.4 times that of the TFR. The charge regions involved in discharges in TFRs exhibit a dipolar charge structure, with the 5 °C layer roughly dividing the upper positive and lower negative charge regions. Conversely, the CCRs feature a typical tripolar charge structure. The dominant dipole charge structure in the TFR results in an increase in the negative charge field below the negative charge region with height, providing a necessary condition for successfully triggering negative TLFs. Furthermore, the horizontal extent of TLFs is positively correlated with their duration and charge transfer. Regions where TLF channels with larger charge transfers propagate tend to have greater maximum radar reflectivity but lower average radar reflectivity compared to regions with TLFs with smaller charge transfer.

DOI: 10.1007/s00376-025-4342-8

Source: http://www.iapjournals.ac.cn/aas/en/article/doi/10.1007/s00376-025-4342-8viewType=HTML