eCite Digital Repository
Studying the variability in the diurnal and seasonal variations in GPS total electron content over Nigeria
Citation
Eyelade, VA and Adewale, AO and Akala, AO and Bolaji, OS and Rabiu, AB, Studying the variability in the diurnal and seasonal variations in GPS total electron content over Nigeria, Annales Geophysicae, 35, (3) pp. 701-710. ISSN 0992-7689 (2017) [Refereed Article]
 | PDF (Published version) 3Mb |
Copyright Statement
© Author(s) 2017. This work is distributed under the Creative Commons Attribution 3.0 Unported (CC BY 3.0) License. https://creativecommons.org/licenses/by/3.0/
DOI: doi:10.5194/angeo-35-701-2017
Abstract
The study of diurnal and seasonal variations in total electron content (TEC) over Nigeria has been prompted by the recent increase in the number of GPS continuously operating reference stations (CORSs) across Nigeria as well as the reduced costs of microcomputing. The GPS data engaged in this study were recorded in the year 2012 at nine stations in Nigeria located between geomagnetic latitudes – 4.33 and 0.72° N. The GPS data were used to derive GPS TEC, which was analysed for diurnal and seasonal variations. The results obtained were used to produce local GPS TEC maps and bar charts. The derived GPS TEC across all the stations demonstrates consistent minimum diurnal variations during the pre-sunrise hours 04:00 to 06:00 LT, increases with sharp gradient during the sunrise period (∼ 07:00 to 09:00 LT), attains postnoon maximum at about 14:00 LT, and then falls to a minimum just before sunset. Generally, daytime variations are found to be greater than nighttime variations, which range between 0 and 5 TECU. The seasonal variation depicts a semi-annual distribution with higher values (∼ 25–30 TECU) around equinoxes and lower values (∼ 20–25 TECU) around solstices. The December Solstice magnitude is slightly higher than the June Solstice magnitude at all stations, while March Equinox magnitude is also slightly higher than September Equinox magnitude at all stations. Thus, the seasonal variation shows an asymmetry in equinoxes and solstices, with the month of October displaying the highest values of GPS TEC across the latitudes.
Item Details
| Item Type: | Refereed Article |
|---|---|
| Keywords: | ionosphere (equatorial ionosphere), diurnal variation, GPS, latitude, magnitude, seasonal variation, total electron content, Nigeria |
| Research Division: | Physical Sciences |
| Research Group: | Space sciences |
| Research Field: | Mesospheric, thermospheric, ionospheric and magnetospheric physics |
| Objective Division: | Environmental Management |
| Objective Group: | Air quality, atmosphere and weather |
| Objective Field: | Atmospheric processes and dynamics |
| UTAS Author: | Bolaji, OS (Dr Olawale Bolaji) |
| ID Code: | 140035 |
| Year Published: | 2017 |
| Web of Science® Times Cited: | 13 |
| Deposited By: | Physics |
| Deposited On: | 2020-07-22 |
| Last Modified: | 2020-08-31 |
| Downloads: | 19 View Download Statistics |
Repository Staff Only: item control page