Infrasound measurements of tornadoes and other severe storm events at close range

Abstract

Recent experimental evidence suggests that, during tornadogenesis and through the life a tornado, acoustic waves at frequencies below human hearing (infrasound) are produced. To date, acoustic data required to identify the fluid mechanism responsible for this infrasound has been limited—often gathered by large fixed installations. The design and deployment of a mobile Ground-based Local Infrasound Data Acquisition (GLINDA) system was completed at Oklahoma State University to expand the number of samples and enable close-range measurements which would mitigate the measurement uncertainty associated with long distance atmospheric propagation. GLINDA has been deployed alongside Oklahoma-based media storm chasers since May 2020 and has already returned data over multiple severe weather events, including tornadic measurements acquired with GLINDA on 22 May 2020 in Lakin, Kansas. The GLINDA-equipped storm chaser vehicle can additionally provide acoustic data on other weather events such as wildfires and winter weather storms as the vehicle is appropriate for sustained, close observation of these environments. This presentation will cover system design, measurement capabilities, and acoustic production by select weather phenomenon.