“At any given moment about 2,000 thunderstorms roll over Earth, producing some 50 flashes of lightning every second. Each lightning burst creates electromagnetic waves that begin to circle around Earth captured between Earth’s surface and a boundary about 60 miles up [the lower ionosphere].
Some of the waves – if they have just the right wavelength – combine, increasing in strength, to create a repeating atmospheric heartbeat known as Schumann resonance.”