Ionospheric Oscillation with Periods of 6–30 Days at Middle Latitudes: A Response to Solar Radiative, Geomagnetic, and Lower Atmospheric Forcing

Abstract

This research studies the medium timescale (6–30 days) ionospheric response over the Wuhan area to solar radiative, recurrent geomagnetic, and lower atmospheric forcing. The ionospheric response is examined by wavelet analysis of the total electron content (TEC) over the Wuhan area from 2001 to 2020. Ionospheric oscillations with periods centering at the harmonic oscillations of the 27-day solar rotation (e.g., 27 days, 13.5 days, 9 days, and 6.75 days) are focused upon. The results show that the quasi-27-day TEC oscillations at the middle latitude have a better overall correlation with solar radiation than recurrent geomagnetic activity, but the correlation between TEC and recurrent geomagnetic activity has a significant increase at the solar minimum stage. As for ionospheric oscillations with periods shorter than 15 days, these oscillations correlate better with recurrent geomagnetic activity. Moreover, a quasi-27-day TEC oscillation event at the middle latitude caused by convective activity from the lower atmosphere was studied. This suggests that lower atmospheric forcing is also an important factor causing ionospheric oscillations. In addition, the ionospheric oscillations over the Wuhan area also show unique regional characteristics, as the regional ionosphere does not respond well to the Kp oscillation with periods shorter than 20 days, particularly, 13.5 days.

Analysis of Ionospheric Anomalies before the Tonga Volcanic Eruption on 15 January 2022

“…By analyzing the changes in space weather parameters (Figures 6-8), we exclude the ionospheric TEC anomalies on 6, 8, 9, 14 and 15 January. In addition to solar and geomagnetic activity, low atmospheric forcing has the potential to contribute to variations in the ionosphere [41,42]. In order to study the effect of low atmospheric forcing on the ionosphere, we simulated the meridional and zonal winds in the lower atmosphere on 5, 6, 8 and 9 January based on the level of geomagnetic activity using the HWM14 model, as shown in Figure 16.…”

Ionospheric TEC Variation and Gravity Waves Signatures During the Solar Eclipse on 21 June 2020 Over Southern China

“…Zhang & Coster, 2019), and internal atmospheric dynamics (C.‐S. Huang et al., 1998; Maurya et al., 2019; Nishioka et al., 2013; K. Wu et al., 2017; Yang, Gu, Qin, Teng, Huang, et al., 2022; Yang, Gu, Qin, Teng, Wei, et al., 2022). Natural hazard events and space weather events such as earthquakes, volcanic eruptions, and solar eclipses can affect the ionosphere by exciting gravity or acoustic waves (Astafyeva, 2019; Chimonas & Hines, 1970; Hegai et al., 2006; John & Kumar, 2013; Meng et al., 2019).…”

“…Solar eclipses provide a unique opportunity to study ionospheric disturbances. Several factors can cause ionospheric disturbances, such as geomagnetic variation (J. Lei et al., 2014; Ren et al., 2020), solar radiation events (Padokhin et al., 2019; Yang, Gu, Qin, Teng, Huang, et al., 2022; Yang, Gu, Qin, Teng, Wei, et al., 2022; S.R. Zhang & Coster, 2019), and internal atmospheric dynamics (C.‐S.…”

Characteristics and Evolution of the Response of the Lower Atmosphere to the Tonga Volcanic Eruption

“…The lower atmosphere refers to the Earth's atmosphere below 25 km in altitude [1]. It includes the troposphere and the lower and middle stratosphere.…”