The Relationship of Lightning Radio Pulse Amplitudes and Source Altitudes as Observed by LOFAR. Issue 4 (21st April 2022)

• Record Type: Journal Article
• Authors: Machado, J. G. O.; Hare, B. M.; Scholten, O.; Buitink, S.; Corstanje, A.; Falcke, H.; Hörandel, J. R.; Huege, T.; Krampah, G. K.; Mitra, P.; Mulrey, K.; Nelles, A.; Pandya, H.; Rachen, J. P.; Thoudam, S.; Trinh, T. N. G.; ter Veen, S.; Winchen, T.
• Is Part Of: Earth and space science. Volume 9:Issue 4(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-21
• Subjects: LOFAR -- lightning -- radio astronomy -- pulse detection -- amplitude -- altitude; Space sciences -- Periodicals; Geophysics -- Periodicals; 500.5
• DOI: 10.1029/2021EA001958
• Languages: English
• ISSNs: 2333-5084

Abstract

Abstract: When a lightning flash is propagating in the atmosphere it is known that especially the negative leaders emit a large number of very high frequency (VHF) radio pulses. It is thought that this is due to streamer activity at the tip of the growing negative leader. In this work, we have investigated the dependence of the strength of this VHF emission on the altitude of such emission for two lightning flashes as observed by the Low Frequency ARray (LOFAR) radio telescope. We find for these two flashes that the extracted amplitude distributions are consistent with a power‐law, and that the amplitude of the radio emissions decreases very strongly with source altitude, by more than a factor of 2 from 1 km altitude up to 5 km altitude. In addition, we do not find any dependence on the extracted power‐law with altitude, and that the extracted power‐law slope has an average around 3, for both flashes. Key Points: We measure the amplitude distribution of lightning very high frequency (VHF) pulses The VHF pulse amplitude spectrum follows a power‐law The top 10‐percentile amplitude decreases with altitude