Measurement and characterization of infrasound from a tornado producing storm

Details

• Journal Title:
  The Journal of the Acoustical Society of America
• Personal Author:
  Elbing, Brian R. ; Petrin, Christopher E. ; Van Den Broeke, Matthew S.
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; WPO (Weather Program Office)
• Description:
  A hail-producing supercell on 11 May 2017 produced a small tornado near Perkins, Oklahoma (35.97, −97.04) at 2013 UTC. Two infrasound microphones with a 59-m separation and a regional Doppler radar station were located 18.7 and 70 km from the tornado, respectively. Elevated infrasound levels were observed starting 7 min before the verified tornado. Infrasound data below ∼5 Hz was contaminated with wind noise, but in the 5–50 Hz band the infrasound was independent of wind speed with a bearing angle that was consistent with the movement of the storm core that produced the tornado. During the tornado, a 75 dB peak formed at ∼8.3 Hz, which was 18 dB above pre-tornado levels. This fundamental frequency had overtones (18, 29, 36, and 44 Hz) that were linearly related to mode number. Analysis of a larger period of time associated with two infrasound bursts (the tornado occurred during the first event) shows that the spectral peaks from the tornado were present from 4 min before to 40 min after tornadogenesis. This suggests that the same geophysical process(es) was active during this entire window.
• Keywords:
  Sound Tornadoes
• Source:
  The Journal of the Acoustical Society of America, 146(3), 1528-1540
• DOI:
  https://doi.org/10.1121/1.5124486
• Document Type:
  Journal Article
• Funding:
  Grant no. NA18OAR4590307
• Rights Information:
  Other
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:91a4ce91450bf44c6fc3f151f63a62d0b91807b933e0e27a084331fecc37f0d3
• Download URL:
  https://repository.library.noaa.gov/view/noaa/27461/noaa_27461_DS1.pdf
• File Type:
  [PDF - 3.38 MB ]