Influence Research of Urbanization on Spatial and Temporal Distribution of Lightning Parameters

YU Tianye; HE Shan; ZHANG Kejie; CHENG Qin; CHENG Chen

doi:10.16032/j.issn.1004-4965.2025.065

Abstract：Investigating the spatiotemporal distribution and urban-suburban differences of lightning parameters is of great practical significance for understanding how the natural environment influences lightning activity and for improving urban lightning disaster prevention.Based on the monitoring data from the VLF/LF 3D lightning location system in Hubei Province(2015-2022),the DBSCAN algorithm was used to identify thunderstorm clusters.On this basis,mathematical and statistical methods are adopted for a comparative study on the distribution characteristics of lightning frequency,polarity,current intensity,and thunderstorm cloud cluster between urban and suburban areas.The results show a higher proportion of cloud lightning in urban areas,and an increasing trend for lightning density both in urban and suburban areas over the past 8 years,while lightning current intensity and average thunderstorm days decreased.The cloud-to-ground(CG)lightning parameters are more significantly affected by urbanization.Specifically,CG lightning density in suburban areas is 14.7%higher than that in urban areas.The average current intensity for both cloud and ground lightning in urban areas is higher than that in suburban areas,which means the CG lightning activity can produce higher lightning current intensity.The probability of current amplitude for CG lightning,which is less than 20 kA,is 6.6%higher in suburban areas when compared to the urban areas,and the shielding failure rate is also higher.Conversely,the probability of a current amplitude exceeding 100 kA is larger than 100 kA,is 0.5%higher in urban areas,and its back flashover rate is also higher.Both areas are dominated by small thunderstorm cloud,with average thunderstorm cluster areas of 77.2 km² and 81.7 km²,respectively.The occurrence probability for small thunderstorms is higher in urban areas,while the probability of large thunderstorms is higher in suburban areas.