Study of the Variability of Ionospheric Total Electron Content over Africa

Birhan, Melese

dc.contributor.author	Birhan, Melese
dc.date.accessioned	2024-11-16T11:10:59Z
dc.date.available	2024-11-16T11:10:59Z
dc.date.issued	2024-10
dc.identifier.uri	http://ir.bdu.edu.et/handle/123456789/16164
dc.description.abstract	Ionosphere, is a thin layer of plasma that occupies the upper layer of the Earth's atmosphere, affecting radio communications, satellite navigation, and space weather. For this reason, monitoring changes in the ionosphere is quite vital. One of the crucial parameters expressing the characteristic of the ionosphere is the total electron content (TEC), which is a function of electron density. This study investigat es the variations in vertical total electron Content (vTEC) of the ionosphere during solar cycle 24, particularly focusing on the solar maximum period (2014 and 2015), over Africa. Its variations during this cycle are essential for enhancing space weather prediction and improving communication and navigation systems. The observational data from ground-based Global Positioning System (GPS), inferred from dual-frequency GPS receivers established at Rabat, Malindi, Zambia, and Yamoussoukro over Africa in the years 2014 and 2015 were used. It was used to study the hourly, diurnal, seasonal, and latitudinal variations in ionospheric vTEC at these GPS stations as insufficient research results of ionospheric variations are available for these areas. Our findings reveal distinct diurnal patterns: vTEC reaches its minimum morning, gradually increases throughout the day, peaks in the afternoon, and then declines after sunset. This behavior is primarily driven by photoionization due to solar radiation. Conversely, nighttime electron loss processes lead to decreased vTEC values. Seasonal variations were also observed, with the highest vTEC recorded during the equinoxes, intermediate values during the June solstice, and the lowest during the December solstice. Additionally, vTEC values were influenced by the latitudinal position of the GPS receivers; higher electron concentrations were found at lower latitudes, diminishing toward the poles. For future research, we want to recommend others use, as far as possible, complete data and consider the long-term studies of these GPS receiver stations to enhance our understanding of ionospheric dynamics.	en_US
dc.language.iso	en_US	en_US
dc.subject	Physics	en_US
dc.title	Study of the Variability of Ionospheric Total Electron Content over Africa	en_US
dc.type	Thesis	en_US