2014: Application of the Schumann resonance spectral decomposition in characterizing the main African thunderstorm center

Journal of Geophysical Research: Atmospheres

DOI: 10.1002/2014JD022613

Michał Dyrda 1,*, Andrzej Kułak 2,3, Janusz Młynarczyk 3, Michał Ostrowski 2, Jerzy Kubisz 2, Adam Michalec 2 and Zenon Nieckarz 4

1) Institute of Nuclear Physics, PAS, Kraków, Poland
2) Astronomical Observatory, Jagiellonian University, Kraków, Poland
3) Department of Electronics, AGH University of Science and Technology, Kraków, Poland
4) Institute of Physics, Jagiellonian University, Kraków, Poland


In this paper we present a new method for quantifying the main tropical thunderstorm regions based on extremely low frequency (ELF) electromagnetic wave measurements from a single station – the Hylaty ELF station in Central Europe. Our approach is basedon Schumann resonance (SR) measurements, which we apply as an example to thunderstorms in Africa. By solving the inverse problem, using the SR power spectrum templates derived analitically, we calculate distances to the most powerful thunderstorm centers and present simplified 1-D thunderstorm lightning activity ”maps” in absolute units C2m2/sec. We briefly describe our method of SR power spectrum analysis and present how this method is used with real observational data. We obtained the monthly lightning activity maps of the African storm centers with a spatial resolution of 1 degree and temporal resolution of 10 minutes for January and August 2011. This allowed us to study the varying location and intensities of the African storm centers in different seasons of the year. A crosscheck of the obtained lightning activity maps with TRMM satellite data recorded by the Lightning Imaging Sensor (LIS), as well as the derived correlation coefficients between SR and optical data were used to validate the proposed method. We note that modeling a maximum possible number of resonance modes in the SR power spectra (in our case 7 resonances) is essential in application of the proposed approach.