Ionospheric signatures of acoustic waves generated by transient tropospheric forcing

Abstract

Acoustic waves generated by tropospheric sources may attain significant amplitudes in the thermosphere and overlying ionosphere. Although they are weak precursors to gravity waves in the mesosphere below, acoustic waves may achieve temperature and vertical wind perturbations on the order of approximately tens of Kelvin and m/s throughout the E and F regions. Their perturbations to total electron content are predicted to be detectable by ground-based radar and GPS receivers; they also drive field-aligned currents that may be detectable in situ via magnetometers. Although transient and short lived, ionospheric signatures of acoustic waves may provide new and quantitative insight into the forcing of the upper atmosphere from below. Key Points AWs in the F-region can induce ∼10s of % perturbations in electron density TEC signatures of AWs are enhanced in magnetic-equatorward direction AW perturbations are imminently observable via GPS/ISR ©2013. American Geophysical Union. All Rights Reserved.