Journal Highlights

Low-frequency sea sounds ring clear at high altitudes


A new study shows microphones suspended from helium balloons in the stratosphere can detect low-frequency sounds from ocean waves. The new method shows promise for detecting acoustic signals from natural disasters and nuclear explosions that cannot always be reliably detected by sensors on the ground, according to the study’s authors.

Infrasound, sounds with frequencies below 20 Hertz, are too low for humans to hear, but come from many sources, including air conditioning units, natural disasters, thunderstorms and whale or elephant vocalizations. Scientists can use infrasound sensors on the ground to pinpoint the location and size of avalanches, meteorite strikes and nuclear explosions, among other events…more