The Modulation of the Quasi‐Two‐Day Wave on Total Electron Content as Revealed by BeiDou GEO and Meteor Radar Observations Over Central China

Abstract

AbstractThe ground‐based total electron content (TEC) observations from BeiDou Geostationary Orbit (GEO) satellites provide more accurate temporal ionospheric variations nearly at the fixed ionospheric pierce points as compared with the non‐GEO TEC. BeiDou GEO TEC measurements during 2016, along with the horizontal wind observations from a collocated meteor radar, are utilized to quantitatively study the ionospheric response to the quasi‐two‐day wave (QTDW) in the neutral atmosphere at Meng Cheng (116.6°E, 33.3°N) over central China. The QTDW peaks during July with amplitudes of ~25–30 m/s for both zonal and meridional winds. It is suggested that the nonlinear interactions between the QTDW and tides and their influences on TEC are insignificant for this QTDW event. Nevertheless, the diurnal tide decreases by ~40–60% during the QTDW episode, which is most likely related to the change of background wind induced by the QTDW. Correspondingly, the 24 h oscillations in TEC decrease by ~18%. In addition, the wind perturbations of the QTDW can also possibly modulate the midlatitude electric dynamo and result in a quasi‐two‐day oscillation (QTDO) of ~1.2 total electron content unit (TECU), about ~10% of the background TEC. Our analysis also shows that the background TEC decreases by ~1 TECU (~8%) when the QTDW reaches maximum amplitude. This is probably related to the thermospheric composition changes (e.g., O and N2) induced by the QTDW dissipation.