Observations of Acoustic Aurora in the 1–16 Hz Range

Summary Acoustic aurora have been heard by long-term residents of the artic. They have also been recorded on microbarographs. Acoustic events associated with aurora are now reported in the near infrasonic range (1–16 Hz) at Barrow, Alaska. These observations were made with the aid of a resonant detector achieving a high signal-to-noise ratio similar to that used in extending the rocket-grenade technique to 109km. Over 100 impulsive events of a quasi-repetitive nature were recorded on a patrol basis during January 1970. Acoustic events were correlated with disturbed magnetic conditions and optical aurora but uncorrelated with lower-frequency auroral microbarograph events at College or Inuvik.
It is hoped that these initial observations will persuade interested parties to a more complete study of this phenomena and encourage an explanation of the generation mechanism for auroral infrasonic waves.