TY  - JOUR
PY  - 2019//
TI  - Measurement and characterization of infrasound from a tornado producing storm
JO  - Journal of the Acoustical Society of America
A1  - Elbing, Brian R.
A1  - Petrin, Christopher E.
A1  - Van Den Broeke, Matthew S.
SP  - e1528
EP  - e1528
VL  - 146
IS  - 3
N2  - 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.<p />  <p>Language: en</p>
LA  - en
SN  - 0001-4966
UR  - http://dx.doi.org/10.1121/1.5124486
ID  - ref1
ER  -