Plain language summary: Every major solar flare shifts the pitch of a 26-second vibration that rings continuously inside Earth and is recorded on seismometers worldwide. This paper explains why — with 20 years of data. A crack in the ocean floor off West Africa acts as a natural resonator: the ocean blows energy through it, and its geometry locks the frequency at exactly 0.038 Hz. When a solar flare strikes Earth’s ionosphere, it drives electrical currents through the crust that squeeze the resonator fluid and raise the pitch within minutes. Slower geomagnetic storms do the same thing over hours. And over decades, the solid inner core oscillates, sending electromagnetic waves through the liquid outer core on a 6-year cycle that sets the baseline sensitivity of the entire system. Four independent datasets — Earth’s rotation rate, geomagnetic jerk timing, satellite magnetic field models, and satellite gravity — now independently corroborate this deep solar-to-core coupling chain.
Paul Hermatz (Fri,) studied this question.