From Wikipedia, the free encyclopedia Duration: 25 seconds.0:25 A simplified artistic animation of Schumann resonance in Earth's atmosphere. A diagram of Schumann resonances in Earth's atmosphere The Schumann resonances (SR) are a set of spectrum peaks in the extremely low frequency portion of the Earth's electromagnetic field spectrum. Schumann resonances are global electromagnetic resonances, generated and excited by lightning discharges in the cavity formed by the Earth's surface and the ionosphere.[1]