Variations of the global lightning distribution revealed from three‐station Schumann resonance measurements

Abstract

[1] Schumann resonance (SR) observations performed simultaneously by a global network consisting of three stations (Lekhta (Karelia, Russia), Moshiri (Hokkaido, Japan), and West Greenwich (Rhode Island, United States)) during almost 1 year were used for mapping world thunderstorm activity. A two-stage inverse problem is solved for locating lightning sources distributed over the Earth's surface from the SR background signals. The first stage consists of inversions of the SR magnetic field power spectra to the distributions of lightning intensity by distance relative to an observation point. The obtained distance profiles of intensity of sources are used as tomographic projections for reconstructing a spatial distribution of sources in the second stage. We have suggested the use of source distance profiles obtained from the spectra of outputs of two orthogonal magnetic antennas operating at each observatory as separate tomographic projections. It is shown that the implementation of additional information on the azimuthal distribution of sources, provided by angular selectivity of magnetic sensors, significantly improves the quality of global lightning mapping under the condition of a limited number of observation stations. Maps of the global lightning distributions constructed by the result of inversions of SR spectra show that the most active regions vary zonally on the seasonal time scale and meridionally on the diurnal time scale being connected mainly with continental areas in the tropics.

Satellite observations of Schumann resonances in the Earth's ionosphere

“…Ultimately, the source of energy of the Schumann resonances is tropospheric lightning. Indeed, multi‐point ground‐based observations of Schumann resonances can be used to locate the lightning sources [e.g., Shvets et al , 2010], even though the resonant wave energy fills the global waveguide. The strength of the Schumann resonances observed in space should depend on the collective strength of the lightning activity in the troposphere.…”

Global Lightning Activity on the Basis of Inversions of Natural ELF Electromagnetic Data Observed at Multiple Stations around the World

“…In this review, we have used only the ELF SR data for a few days because the Surv Geophys (2011) 32:705-732 729 treatment of ELF tomography mapping is a rather tough job. Recently, we have applied this ELF tomography technique to a much longer period of 1 year and our paper has just appeared (Shvets et al 2010). The same three stations as in this review have been utilized in Shvets et al (2010), and maps of the global lightning distributions for 1 year constructed by the ELF inversion show that the most active regions vary zonally on the seasonal time scale.…”

“…Recently, we have applied this ELF tomography technique to a much longer period of 1 year and our paper has just appeared (Shvets et al 2010). The same three stations as in this review have been utilized in Shvets et al (2010), and maps of the global lightning distributions for 1 year constructed by the ELF inversion show that the most active regions vary zonally on the seasonal time scale. Also, it is suggested by them that the implementation of additional information on the azimuthal distribution of sources, provided by angular selectivity of magnetic sensors, significantly improves the quality of global lightning mapping under the condition of a limited number of ELF observing stations.…”

Lightning and middle atmospheric discharges in the atmosphere

“…Global distribution of lightning activity is obtained using global inversion technique for the Schumann resonance data collected at either a single station/multiple stations (Williams, 1992;Satori et al, 1996;2009bHobara et al, 2006;Williams et al, 2010;Shvets et al, 2010;Shvets and Hayakawa, 2011;Yamashita et al, 2011;Mushtak and Williams, 2011;Williams and Mareev, 2014). The diurnal variation of the cumulative intensity of the first three Schumann resonant signals observed at Nagycenk, Hungary for the Years 1994-1998 clearly showed peaks at 0700-0900 UT, 1400-1600 UT and 1900-2100 UT (Satori et al, 2009b(Satori et al, , 2013 corresponding to intense tropical thunderstorm activity over South East Asia, Africa and South America.…”