Investigation of Acoustic Waves in the Ionosphere Generated by a Deep Convection System Using Distributed Networks of GPS Receivers and Numerical Modeling

Acoustic waves generated in the lower atmosphere may become an important source of variability in the upper atmosphere. Although excited with small amplitudes compared to gravity waves, they are minimally subjected to viscous dissipation and may reach large amplitudes at F region altitudes. We present total electron content data from a dense network of ground-based GPS receivers during an outbreak of severe weather over Kansas on 26 May 2016. The results show annular traveling ionospheric disturbances (TIDs) propagating radially outward from the center of the storm. The TID characteristics were consistent with acoustic waves in the infrasonic range. We have modeled the disturbance by including a heat source representing latent heat release from a large thunderstorm. The modeled disturbance at ionospheric altitudes resembles the TIDs in terms of phase speed, frequency, and horizontal wavelength. We conclude that the observed TIDs were caused by an acoustic wave generated by deep convection.