ultra low frequency wave

physics

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July 14, 2026

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Ultra low frequency (ULF) waves are electromagnetic waves with very low frequencies, typically ranging from 1 to 1,000 megahertz, or periods of 1 to 1,000 seconds. These waves are a major source of variations in Earth's magnetic field, causing minute oscillations known as magnetic pulsations.1

ULF waves originate in Earth's outer magnetic field and travel along field lines to the surface. They can be generated by various mechanisms, including resonant oscillations of Earth's magnetic field in response to solar wind waves, disturbances on the magnetopause, or sudden changes in solar wind flow. These waves are of interest for communication systems, particularly for submarines, due to their ability to penetrate seawater with relatively weak absorption.123

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geomagnetic field
Magnetohydrodynamic waves—magnetic pulsations
…class of electromagnetic waves called ultralow-frequency (ULF) waves, with frequencies from one to 1,000 megahertz. Because the frequencies are so low, the waves are usually characterized by their period of oscillation (one to 1,000 seconds) rather than by frequency.
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…class of electromagnetic waves called ultralow-frequency (ULF) waves, with frequencies from one to 1,000 megahertz. Because the frequencies are so low, the waves are usually characterized by their period of oscillation (one to 1,000 seconds) rather than by frequency.
Read More