Physics Journal
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Physics Journal, Vol.1, No.2, Sep. 2015, Pub. Date: Sep. 1, 2015
Characterizing the Maximum Electron Density of the F2 Layer (NmF2) in the Equatorial Ionosphere
Pages: 137-152 Views: 2412 Downloads: 1111
[01] A. Ogwala, Department of Physics, Lagos State University, Ojo, Lagos.
[02] E. O. Somoye, Department of Physics, Lagos State University, Ojo, Lagos.
[03] E. O. Onori, Department of Physics, Lagos State University, Ojo, Lagos.
[04] R. A. Adeniji-Adele, Department of Physics, Lagos State University, Ojo, Lagos.
A study of the Maximum Electron Density of the F2 layer (NmF2) in the ionosphere over the African, Asian and American sectors is presented. Mean NmF2 and NmF2 coefficient of variability (CV) of three ionosonde stations namely Dakar (14.8°N, 17.4°, 16.1°N dip) in the African sector, Manila (14.7°N, 121.1°E, 14.2°N dip) in the Asian sector and Huancayo (12°S, 75.3°W, 1.9°N dip) in the American sector were used for this study during three epochs of solar cycle: 1982, year of high solar activity (HSA) with monthly average sunspot number, Rz12 (115.9), 1983, year of moderate solar activity (MSA) with monthly average sunspot number, Rz12 (68.7) and 1986, year of low solar activity (LSA) with monthly average sunspot number, Rz12 (13.4). Results obtained show that pre- and post-noon peaks bothering the noon bite-out were present in the diurnal curves of mean NmF2 for the three stations. Morning peaks were predominant during HSA while afternoon peaks were predominant during MSA and LSA. NmF2 CV is characterized by pre- and post-midnight peaks in all the three stations. The results reveal diurnal, seasonal, solar cycle and longitudinal influences of mean NmF2 and NmF2 CV.
Mean NmF2, NmF2 CV, Diurnal, Seasonal, Solar Activity, Noon Bite-Out
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