Analysis on the Lightning Flash Activities Over Beijing Area Based on Beijing Lightning Network

The temporal and spatial distribution characteristics of lightning flashes in Beijing area during 146 thunderstorms in 2015-2017 were statistically analyzed on the basis of lightning location data from the Beijing Lightning Location Network (BLNET). The results showed that 588,520 lightning flashes in total were observed, most of which were intra-cloud lightning flashes (IC) accounting for about 93.8%. Cloud-to-ground lightning flashes (CG) accounting for only 16.2% of the total flashes, and 11.7% of CG lightning flashes were positive CG lightning flashes. The daily change in lightning activity appears a double-peak, with frequent lightning flash occurrences at 14:00-22:00 (Beijing Local Time) and 23:00-the next day at 03:00. The total lightning activity density shows interannual differences from 2015-2107. The temporally averaged flash distribution shows that there are several regions with higher flash density that mainly located in the urban areas and might be closely related to dense population, heavy traffic and aerosol density.