We present a study on the relationship between upward propagating gravity waves and ionospheric irregularities. Gravity waves (GWs) are identified from Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite temperature measurements and nighttime ionospheric irregularities are observed from the three Swarm satellites. Using these two independent set of measurements, we investigate the relationship between gravity waves and ionospheric irregularities on both equinox and solstice seasons for the years 2018–2019. The results show, post‐sunset gravity wave characteristics are important in understanding the variability of global nighttime equatorial plasma density irregularities. We also find out that the pre‐midnight and post‐midnight characteristics of ionospheric irregularities show global westward shift in the occurrence of ionospheric irregularities. Upward propagating gravity waves also show three dominant peaks longitudinally with the strongest being between American and African longitudinal sectors. Strongest gravity wave amplitudes are associated with strongest plasma irregularities. GW suppression is observed around equatorial regions at stratopause region in our measurements which are commonly observed at polar and higher latitudinal regions in many studies. We also observe that, ionospheric irregularities are strongest when GWs are relatively less suppressed.

This study investigates the ionospheric response to a geomagnetic storm triggered by a Coronal Mass Ejection (CME) during 6–9 September 2017, across GPS stations located in diverse geographical regions. We analyze the changes in the magnetic field component (ΔH), the Prompt Penetration Electric Fields (PPEF), and the Total Electron Content (TEC). We find that ΔH exhibits latitude-dependent responses during the storm, with high-latitude stations experiencing more significant reductions compared to low-latitude stations. The PPEF behavior is found to be directly correlated with solar wind disturbances. Particularly during the main phase of the storm, fluctuations in PPEF were clearly associated with negative values in the Dst index. The KIRU station, located at a high latitude, shows the most pronounced PPEF effects, indicating the increased susceptibility of high-latitude regions to solar wind interactions. The time series plot of TEC, covering a full month at different stations, shows a distinct diurnal pattern driven by solar ionization. Equatorial stations such as HYDE, BOU, HON (HNLC), and DODM exhibit the highest daily TEC values. During the geomagnetic storm, TEC disturbances are evident across all stations, with significant disturbances and varying trends in TEC depletion rate observed at different locations. The TEC values differ by 5–25 TECU during the storm period, suggesting intricate ionospheric responses to geomagnetic storms at different stations. This highlights the importance of considering different geographical regions to fully understand the ionospheric dynamics related to solar activities.

This work investigates the relationship between cosmic ray intensity (CRI) and key interplanetary and geomagnetic parameters during both disturbed (November 1–6, 2021) and quiet (November 7–12, 2021) periods. Four neutron monitor stations, namely BKSN, DOMC, JUNG, and MXCO, are employed to analyze the behavior of CRI in response to variations in southward interplanetary magnetic field (IMF Bz), interplanetary electric field (IEF Ey), solar wind speed (Vsw), and geomagnetic indices, including Kp and Dst. During the storm period, time series plots reveal significant Forbush Decreases (FD) in CRI at all stations. These FDs exhibit distinct characteristics, with the most substantial reduction observed at high-latitude stations and the least at low-latitude stations. Notably, the Mexico station, situated in the low-latitude region, records higher neutron counts for both disturbed and quiet periods compared to the middle (BKSN and JUNG) and high-latitude (DOMC) stations. Cross-correlation analysis is employed to examine the relationships between CRI and the aforementioned parameters. Results indicate that during the geomagnetically disturbed period, CRI exhibits negative correlations with IMF Bz, Vsw, and Kp index, while demonstrating positive correlations with Dst and IEF Ey. The strongest correlation is observed between CRI and Dst, suggesting that it can affect variations in cosmic rays measured on Earth, during the geomagnetic storms. In contrast, during the quiet period, significantly weaker correlation was observed than the disturbed period. However, at the JUNG station, CRI displays good correlations with all considered parameters even during the quiet period. The station-specific correlations signifies the importance of geographic location in shaping the response of CRI to external influences.