Investigation of the Variability of Night‐Time Equatorial Thermospheric Winds Over Nigeria, West Africa

Rabiu, Babatunde; Okoh, Daniel; Wu, Qian; Bolaji, O. S.; Abdulrahim, R. B.; Dare-Idowu, Oluwakemi; Obafaye, Aderonke

doi:10.1029/2020ja028528

Cited by 7 publications

(3 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Typical meridional and zonal wind measurements using Fabry Perot Interferometer during diurnal and geomagnetic storm periods over the African region have been studied and analyzed (Kaab et al., 2017; Malki et al., 2018; Rabiu et al., 2021; Tesema et al., 2017). We can comment on the diurnal variation of neutral winds, that is poleward meridional winds in the evening that turn equatorward at around midnight and eastward zonal winds in the evening that turn westward towards the sunrise in the northern winter hemisphere.…”

Section: Resultsmentioning

confidence: 99%

The Ionospheric Dynamics of the African Sector Responding to a Severe Geomagnetic Storm; the Storm of 3–5 November 2021

Rukundo

2023

Space Weather

View full text Add to dashboard Cite

A geomagnetic storm is a disturbance on the Earth's magnetic field resulting from enhanced energy transfer from interplanetary space to the Earth's environment through the magnetosphere. The cause of geomagnetic storms is variation in the solar wind parameters, that is enhancement in solar wind speed and solar wind particles that increase solar wind pressure, and at least >3 hr sustained southward interplanetary magnetic field (IMF) on the day side magnetosphere (Gonzalez et al., 1994;Kumar & Kumar, 2019). The major solar driver of this disturbance is the coronal mass ejections (CMEs) embedded with large plasma emissions from the sun, taking several hours or days to reach the Earth's atmosphere. It should be noted that other sun's emissions like high solar wind speed from coronal holes, and corotating interaction regions also contribute to geomagnetic storms (Richardson, 2018;Richardson et al., 2006). The geomagnetic storm effects induce ionospheric disturbances characterized

show abstract

Section: Resultsmentioning

confidence: 99%

The Ionospheric Dynamics of the African Sector Responding to a Severe Geomagnetic Storm; the Storm of 3–5 November 2021

Rukundo

2023

Space Weather

View full text Add to dashboard Cite

show abstract

“…They found that the longitudinal variation in the drift was related to the changes in the zonal currents driven by meridional winds at F region height of the equatorial ionosphere. It had been recently found that, changes in the thermospheric neutral winds are the reason for the longitudinal differences that have been re-ported in equatorial electric fields between the West and East Africa stations [14] [43] [44]. They found that, in general, the neutral wind speed observed in eastern African sector is weaker and stronger in west African sector compared with speeds observed in other longitude sectors.…”

Section: Discussionmentioning

confidence: 99%

Longitudinal Variability of the Vertical Drift Velocity Inferred from Ground-Based Magnetometers and C/NOFS Observations in Africa

Honoré¹,

Amaechi²,

Daïka³

et al. 2022

IJG

View full text Add to dashboard Cite

This study aims at discussing longitudinal effects on the variability of the vertical E × B drift velocity at low latitudes, specifically over African sector. To this effect, observations from ground-based magnetometers and the Ion Velocity Meter experiment onboard C/NOFS satellite are analyzed in conjunction with equatorial electric field and neutral wind model estimates under geomagnetically quiet conditions in the years 2012-2013. Notwithstanding the limitation in data over Africa, the combination of ground-based and in-situ observations confirmed the existence of longitudinal differences in the E × B between the Atlantic, Western and Eastern African sectors. This was well reproduced by the equatorial electric field model (EEFM) which showed that during noon, the peak of the equatorial electric field (EEF) was the lowest in the Atlantic sector, with an increasing trend towards the Eastern longitude. The Horizontal Wind Model 14 (HWM14) showed that the eastward zonal (poleward meridional) wind velocity was the lowest (highest) in the Eastern sector. Furthermore, the zonal (meridional) wind increased (decreased) from the Eastern to the Atlantic sector. These results highlight the contribution of the neutral wind velocity in driving the longitudinal difference in the vertical How to cite this paper: Honoré, M.E.,

show abstract

“…The first East African nighttime equatorial thermospheric wind and temperature results show many similarities and differences between Brazil and Peru (Tesema et al., 2017). Another study of the equatorial thermospheric winds was conducted using an FPI located in Nigeria (Rabiu et al., 2021). The results indicated that the zonal winds ranged from −124 to 163 m/s, and the meridional winds ranged from −70 to 95 m/s.…”

Section: Introductionmentioning

confidence: 99%

Passive Optical Observation of Mesosphere and Thermosphere Wind Over Three Stations in China

Wei,

Gu,

et al. 2024

JGR Space Physics

View full text Add to dashboard Cite

Fabry Perot interferometer (FPI) is an essential ground‐based passive optical observation device to detect middle and upper atmospheric information. Three FPIs are located at Kunming (103.8°E, 25.6°N), Xinglong (117.4°E, 40.2°N), and Mohe (122.3°E, 53.5°N), China. The diurnal and annual variation of night wind at 87, 97, and 250 km are investigated from 2019 to 2021, compared to Horizontal Wind Model 14 (HWM14) to check the prediction accuracy for the local wind field. Our results are as follows: (a) At 87 km, the zonal winds are similar in Kunming and Xinglong, but the meridional winds are generally stronger in Kunming. The zonal and meridional winds in both locations are dominated by semidiurnal variations. (b) At 97 km, the duration of semidiurnal variation of zonal winds and diurnal variation of meridional winds in Kunming is long, which is opposite to that of Xinglong. (c) At 250 km, the wind speed increases with latitude for both zonal and meridional winds, which are both dominated by diurnal variations for all the three sites. Unlike 87 and 97 km, the entire wind field at 250 km is dominated by annual variation, except for a significant semiannual variation at midnight in Mohe. (d) Overall, the HWM14 predictions are stronger than the FPI measurements at peak wind speeds and similar at 87 and 97 km, which surpasses the performance at 250 km. Especially at 250 km, the model results are worse for the zonal winds of Kunming and the meridional winds of Mohe. These results will help to understand the wind field in the middle and upper atmosphere and improve the accuracy of the model.

show abstract

Investigation of the Variability of Night‐Time Equatorial Thermospheric Winds Over Nigeria, West Africa

Cited by 7 publications

References 49 publications

The Ionospheric Dynamics of the African Sector Responding to a Severe Geomagnetic Storm; the Storm of 3–5 November 2021

The Ionospheric Dynamics of the African Sector Responding to a Severe Geomagnetic Storm; the Storm of 3–5 November 2021

Longitudinal Variability of the Vertical Drift Velocity Inferred from Ground-Based Magnetometers and C/NOFS Observations in Africa

Passive Optical Observation of Mesosphere and Thermosphere Wind Over Three Stations in China

Contact Info

Product

Resources

About