Modern aspects of Schumann resonance studies

Schumann resonance (SR) is an electromagnetic extremely low frequency (ELF) phenomenon that occurs in the natural cavity formed by the Earth's surface and the lower ionosphere. Electromagnetic radiation of global thunderstorms is the source of ELF oscillations. Schumann resonance studies provide valuable information on the properties of the lower ionosphere together with the characteristics of planetary lightning activity. In the present article, modern aspects of the Schumann resonance studies are discussed based on numerical simulations of the ELF radio signals.