Ionospheric Perturbations Due to Large Thunderstorms and the Resulting Mechanical and Acoustic Signatures

Abstract

Perturbations from thunderstorms can play a notable role in the dynamics of the ionosphere. In this work, ionospheric perturbation effects due to thunderstorms were extracted and studied. Thunderstorm-associated lightning activities and their locations were detected by the World-Wide Lightning Location Network (WWLLN). The mechanical components of ionospheric perturbations due to thunderstorms were extracted from the total electron content (TEC), which was measured at selected thunderstorm locations using the polynomial filtering method. Further analyses were conducted using wavelet analysis and Discrete Fourier Transform (DFT) to study the frequency modes and periodicities of TEC deviation. It was revealed that the highest magnitudes of TEC deviations could reach up to ~2.2 TECUs, with dominant modes of frequency in the range of ~0.2 mHz to ~1.2 mHz, falling within the gravity wave range and the second dominant mode in the acoustic range of >1 mHz to <7.5 mHz. Additionally, a 20–60 min time delay was observed between the sprite events, the other high-energy electrical discharges, and the time of occurrence at the highest peak of acoustic-gravity wave perturbations extracted from TEC deviations. The possible mechanism responsible for this phenomenon is further proposed and discussed.

Periodic Oscillation of VLF Transmitter Signals Measured in Low and Middle Latitude Regions

“…Using the TEC and temperature data, Chang et al (2011) investigated the upward-moving planetary waves during an intense quasi-2-day wave event in the mesosphere and lower thermosphere (MLT) region between 1 December 2005 and 28 February 2006. Thunderstorm activity can also lead to ionospheric perturbation and wavelike TEC structure have been found and suggested to be related with acoustic gravity waves (Ogunsua et al, 2020(Ogunsua et al, , 2023.…”