Relationship Between Lightning Activity and Terrain in High-Altitude Mountainous Areas

In China, the average elevation of Yunnan Province exceeds 2000 m, with a greatly fluctuating terrain. Most areas have a high-altitude mountainous terrain and relatively high ground lightning activity. Topography is one of the most critical factors affecting regional lightning characteristics. Therefore, clarifying the quantitative relationship between cloud-to-ground lightning activity and topography can help evaluate the risk of hazard-pregnant environments and adopt active protective measures. In this study, we used a mathematical statistical method to analyze the correlation between cloud-to-ground lightning density and altitude, slope, slope aspect, topographic position index, and land-cover type in Yunnan for the past 10 years. We also used the Apriori algorithm to study the coupling effects of different topographic factors and mine the topographic attribute sets that strongly correlate with high-level lightning activity. We used the entropy weight method to construct a comprehensive index of hazard-pregnant environments and quantitatively evaluate the impact weights of different factors on cloud-to-ground lightning activity. Correlation analysis of lightning density and sensitivity indicated a correlation coefficient of 0.473 between both factors, highlighting the effectiveness of evaluating regional lightning risk with the sensitivity of a hazard-pregnant environment.