## 8 Conclusions  
The evolution of temporal and spatial characteristics of urban lightning activity has always been a research focus and challenge. It is also an essential scientific foundation for conducting local severe thunderstorm forecasting, including timing, fixed-point, quantitative, and refined predictions. This paper reviewed the research results on the impact of urbanization on the regional thunderstorm process and lightning activity in recent years and summarized the existing research deficiencies and future research directions in regard to aerosols, the urban thermal effect, the urban dynamic effect, building forms, and so on. Currently, research on the temporal and spatial characteristics of urban lightning lacks support from stable and long-term, ground-based lightning detection data. In terms of the role of air pollutants, there is no consensus on whether aerosols serve to enhance or inhibit lightning activity. With respect to the urban thermal effect, the UHI effect has a certain enhancement effect on thunderstorm processes and lightning activity. Additionally, the urban dynamic effect results in the peak center of lightning appearing at the edge of a built-up  
Figure 13: Functional relationship between \(E_{stab}\) and height [85]. area. Furthermore, the building height is also a factor that affects thunderstorm processes and lightning activity. In summary, scholars have made progress in understanding the characteristics and drivers of urban lightning activity in recent years, yet there remain several shortcomings:  
1. How to analyze comprehensively the spatiotemporal patterns of urban lightning activity under different thunderstorm intensity backgrounds? To address this knowledge gap, future research could categorize thunderstorm intensity based on parameters such as the lightning frequency, radar echo intensity, and thunderstorm duration. Subsequently, these distinct categories of thunderstorms could be subjected to further statistical analysis to elucidate the spatiotemporal characteristics of urban lightning activity within each intensity level. 2. How to conduct analysis to investigate the influence of alterations in the boundary layer structure, water-heat energy balance, and water vapor circulation processes on urban lightning activity in the context of urbanization? The existing observation data for urban lightning research are primarily from conventional data sources, such as surface automatic stations, Doppler radars, and wind profilers, etc. With the continuous advancement of technology, the detection of the urban boundary layer has entered a new period. Taking a phased-array radar as an example, it has a flexible beam control capability and can greatly enhance the observation ability of the vertical structure. In the future, it is necessary to expand the utilization of unconventional data sources to conduct in-depth analysis on the impact of the boundary layer structure, the water and heat energy balance, as well as changes in water vapor circulation processes on lightning activity in the context of urbanization. 3. How to couple numerical models of different scales to enhance the understanding of the impact of complex underlying surfaces on urban lightning activity? Except for comprehensive observations, numerical simulation has also been utilized by numerous scholars to analyze the impact of cities on thunderstorm processes. Researchers have investigated the evolution mechanism of urban thunderstorms by coupling the weather research and forecasting model (WRF) with the urban canopy model (UCM). Computational fluid dynamics (CFD) is suitable for local and block scales in numerical models and can be utilized to explore the relationship between the near-surface thermal dynamic field and the morphological characteristics of the underlying surface.