A Statistical Analysis of Impact of Tropical Monsoon Seasons on Narrow Bipolar Pulse Characteristics

Abstract

Narrow Bipolar Pulse remain a critical area of research for understanding lightning physics. With advancements in interferometry, LMA, and wavelet analysis, the ability to map and characterize these phenomena has significantly improved. However, there remains a need for deeper exploration into their interaction with physical changes property such as monsoon seasonal effect and their role in larger thunderstorm dynamics. This paper presents an improvement of the statistical information on Narrow Bipolar Pulse during Southwest Monsoon. The electric fields generated by Narrow Bipolar Pulse were recorded using High Speed Transient Recorder (Lecroy HDO4024) with 40 nanosecond resolutions in 2 seconds duration. The Narrow Bipolar Pulses (NBPs) from the South-West Monsoon season (May 2018) consist of 149 samples while 55 samples were gathered during North-East Monsoon (November 2016). In South-West Monsoon, 22 were identified as isolated NBPs, while 127 were associated with cloud-to-ground (CG) and cloud flashes. In contrast, during the North-East Monsoon, 55 NBP samples were gathered, of which 46 were classified as isolated NBPs. Furthermore, 9 samples were characterized as NBPs associated with negative CG flashes. The study found that NBPs occur much less frequently during the North-East Monsoon compared to the South-West Monsoon. This suggests that tropical monsoon seasons significantly impact the generation of Narrow Bipolar Pulses.