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Lightning channel morphology depends on the thunderstorm cloud charge structure, which in turn is influenced by the thunderstorm dynamics. In this paper, based on three‐dimensional radiation source localization data from the Lightning Mapping Array and radar‐based data, our analysis shows that the overall morphology and detailed morphology of the lightning channel correspond to different eddy dissipation rate (EDR) characteristics. Lightning with complex channel morphology occurs in regions with large EDRs. In single lightning events, channels that extend directly within a certain height range without significant bifurcation and turning tend to propagate in the direction of decreasing EDRs, while channel bifurcations and turns usually occur in regions with large radial velocity gradients and large EDRs. This study shows the relationship between channel morphology and thunderstorm dynamics and provides a new method for the direct application of channel‐level localization data to understand thunderstorm dynamics characteristics. Plain Language Summary: Turbulence in thunderstorms affects the charge distribution, which in turn affects the lightning channel morphology. Thus, the lightning channel morphology can reflect the characteristics of turbulence. The current understanding of the correlation between the two is still limited to the relationship between macroscopic thunderstorm dynamic characteristics and lightning activity. In this paper, the relationship between the morphology of the lightning channel and turbulence characteristics is investigated based on the Lightning Mapping Array (LMA) localization data and the cube root of the eddy dissipation rate (EDR) estimated from KABX radar‐based data. The turbulence strength affects the overall morphology of lightning, and lightning with complex morphology tends to occur in regions with large EDRs. In single lightning events, channels extending directly within a certain altitude range tend to propagate in the direction of decreasing EDRs, and lightning channel bifurcation or turning tends to occur in regions with large EDRs. This paper establishes the relationship between thunderstorm electricity and thunderstorm dynamics by using lightning channel morphology as a bridge and provides a new method for the direct application of channel‐level localization data to understand thunderstorm dynamics characteristics. Key Points: The morphology of lightning channels can reflect the distribution of turbulence intensity, and a certain correlation between the two existDirectly extended lightning channels tend to propagate in the direction of decreasing eddy dissipation ratesThe location of the channel bifurcations or turns often corresponds to regions with high eddy dissipation rates [ABSTRACT FROM AUTHOR]

The lightning channel morphology is closely related to developmental processes, which depends on the charge structure. There is currently a lack of understanding of how lightning channel morphology reveals developmental characteristics and charge structure. Based on the Lightning mapping array radiation source localization data of six lightning flashes, we studied the lightning channel morphology characterization method and obtained the spatial distribution of the fractal dimension (FD). We found that the fractal distribution had a consistent spatial and temporal correspondence with the channel development characteristics. Compared to regions with unidirectional extended channels, regions with more channel branches or direction change of channel development have a larger FD and a higher power density, where horizontal channel development is accelerated. These correspondence features reflect the inhomogeneous presence of pocket charge, which provides a new method to use lightning morphology information to reveal the characteristics of charge level distribution within thunderstorm clouds. Plain Language Summary: The charge distribution within the horizontal charge region may have a more significant effect on the extension of the lightning channel. At present, it is still difficult to directly observe the charge structure of thunderstorm clouds, especially the horizontal charge structure. Also, the morphological study of the channel is not perfect due to the limitations of observation and data acquisition. Therefore, there is currently a lack of understanding of how lightning channel morphology reveals developmental characteristics and charge structure. In the paper, the relationship between the lightning channel morphology, developmental characteristics, and charge structure was investigated for the first time based on Lightning mapping array localization data, and the spatial distribution of the lightning fractal dimension (FD) was obtained. It is found that, compared to regions with unidirectional extended channels, regions with more channel branches or direction change of channel development have a larger FD and a higher power density, where horizontal channel development is accelerated. These correspondence features reflect the inhomogeneous presence of pocket charge, which provides a new method to use lightning morphology information to reveal the characteristics of charge level distribution within thunderstorm clouds. Key Points: The spatial distribution of fractal dimension (FD) is obtained, and uesd to describe lightning channel morphologyThe channel morphology characterized by the FD is closely related to channel development velocity and radiation power densityThe channel morphology can be used to reflect the inhomogeneous state of charge level distribution [ABSTRACT FROM AUTHOR]

The connections of lightning radiation sources along channels are greatly affected by the radiation source density, and the channel length is geometrically scaled when neglecting repeated discharges in the same channel. Based on lightning mapping array (LMA) three‐dimensional radiation source location data of two lightning flashes, this study presents a radiation source connection method considering the source density and repeated discharges in channels that includes two steps: the connection of radiation sources and the connection of segments. After increasing the spatial connection threshold determined by the source density, the stability of the channel scale under different detection capabilities (source densities) is improved compared with that of the traditional fixed spatial threshold method. The channel growth rate of the low‐density case reaches 120.99%, which is close to the real situation, and the connection shape is consistent with the real situation. For repeated discharge paths, by limiting the time interval of the radiation source connection, the optimized threshold obtained in this paper can distinguish between discharges occurring in the same channel at different times. Compared with the geometric scale, the discharge scale is significantly larger (∼2.8 times the geometric scale in one case) and can better characterize both the lightning discharge process and the affected area. These comprehensive results show that the proposed method can reduce the number of incorrect connections, increase the channel length, and obtain a more realistic discharge scale. Key Points: A LMA radiation source connection method considering the source density and repeated discharges in channels is proposedThe stability of lightning channel scale under different radiation source densities caused by different detection capabilities is improvedThe obtained discharge scale can track the lightning discharge process and better characterize the impact range of lightning discharge [ABSTRACT FROM AUTHOR]