Schumann resonances

Schumann resonances are low-frequency electromagnetic waves that occur in the Earth's atmosphere, specifically between the Earth's surface and the ionosphere. They are caused by lightning strikes which create electromagnetic pulses that resonate at specific frequencies, the fundamental one being around 7.83 Hz. These resonances act like a cavity that can trap and amplify these waves, similar to how sound resonates in a musical instrument. Scientists study Schumann resonances to monitor global lightning activity and understand aspects of Earth's climate and electromagnetic environment.