Current Understanding of the Equatorial E × B Drift velocities in the African Sector: A Short Review B. O. Adebesin, J. O. Adeniyi, I. A. Adimula, S. J. Adebiyi, S. O. Ikubanni, et al. Journal of the Nigerian Society of Physical Sciences, 2022 A short review of the pattern and morphology of the equatorial plasma drift velocities, particularly during the evening-time Pre-reversal enhancement (PRE) period in the African region had been presented. The seasonal PRE peak values across some locations in the West-African region were considered and compared with other sectors of the world. While most plasma drift observations in the African region were calculated from ionosonde measurements, the observations from other sectors involved direct measurement from satellite and the Incoherent Scatter Radar (ISR) observations. The importance of the PRE in ionospheric electrodynamics was highlighted, the better in the use of either the virtual or real heights of the F-layer in inferring vertical drift velocities were enumerated, revealing the strengths and weakness of each method. The general observations revealed that PRE peak magnitude is commonly weaker in the African region in comparison with the American/Peruvian and Indian sectors, seasonal and solar activity dependent, and could be higher during either magnetic quiet or disturbed activity than when both magnetic activity conditions are combined. The first work to present a regional PRE model around the African equatorial ionization anomaly region (Adebesin et al model) was mentioned. The relevance of the E × B drift in quantifying the daytime equatorial electrojet (EEJ) current was also discussed.
Characterization of seasonal and annual variation of horizontal component of magnetic field in Africa and Asia regions A O Idowu, I A Adimula, G I Ojerheghan Journal of Physics Conference Series, 2021 This study considered the horizontal component of the magnetic field, H, which is a characteristic of Equatorial Electrojet (EEJ). Using Magnetic Data Acquisition System (MAGDAS) data preserved for the year 2009, variations in H strength were determined in 10 stations in Africa and Asia sector. The seasonal and annual fluctuations in the H-component of the Earth’s magnetic field were studied using hourly data of the horizontal magnetic field component. For the hourly fluctuation, the baseline values of H were estimated using the average values around local midnight hours between 2300 and 0200 local-time (LT) and subtracted from other hourly values; for seasonal and yearly analysis, the monthly and annual averages were computed. In all seasons, seasonal variations were higher in equatorial stations than in anti-equatorial stations, while maximum values of SqH were recorded in the equinoctial season, with an annual highest peak value of 70.96 nT in Langkawi (LKW; 6.30°S, 99.78°E) and the lowest peak value of 27.45 nT in Cooktown (CKT; 15.48°N, 145.25°E) both at 1300 LT.
Ursi-ng conference 2021 on the future of radio communication: Prospects and challenges I. Adimula, J. Ojo, Samuel Toluwalope Ogunjo, M. Ajewole, S. Falodun, et al. Journal of Physics Conference Series, 2021 I.A Adimula1, J. S. Ojo2, S. T. Ogunjo2, M.O Ajewole2, S.E Falodun2, A. A Willoughby3, and M. R Usikalu4 1 Department of Physics, University of Ilorin, Ilorin, Kwara State, Nigeria 2 Department of Physics, Federal University of Technology Akure, Ondo State 3 Department of Physics, Redeemer’s University Ede, Osun State 4 Department of Physics, Covenant University, Ota, Ogun State, Nigeria Email: ojojs_74@futa.edu.ng, josnno@yahoo.com, adimula@unilorin.edu.ng List of Organizing Committee, Scientific Committee, Editorial Committee, Invited Speakers, Sponsors, are available in this pdf.
Inter-hemispheric comparison of ionospheric tec variation at each latitudinal band during quiet geomagnetic condition Shola Adebiyi, Isaac Adimula, Olushola Oladipo Journal of the Nigerian Society of Physical Sciences, 2020 This paper compares the quiet time variation of the Total Electron Content (TEC) over four stations located at high and mid latitudes in the northern and southern hemispheres of the African-European longitudes. Five years Global Positioning System (GPS) data, from 2002 to 2006, representing the periods of high to low solar activities were used for the study. Generally, the maximum diurnal values of TEC are observed between 10:00 – 14:00 LT in all the stations during the periods investigated. The minimum values of TEC are observed during the pre-sunrise hours for the two mid latitude stations and around the pre-midnight/post-midnight for the high latitude stations. The maximum values of TEC, however vary with season, latitude and solar activity in all the stations. The values decrease with increase in latitudes and decrease in solar activity. The values range between 10 – 32 and 11 – 50 TECU respectively, for high and mid latitudes for all the years considered. Seasonally, the highest values of TEC are generally observed during the equinoxes in all the stations except at the southern mid latitude station where it can as well be observed in summer, particularly during the Moderate Solar Activity (MSA) and Low Solar Activity (LSA) periods. The lowest values of TEC are observed in winter in all the stations in the southern hemisphere and can be observed in both winter and summer for stations in the northern hemisphere depending on the latitude and solar activity period. TEC variation also exhibits (1) asymmetry in the equinoctial values in all the stations and the magnitude is most pronounced during the period of High Solar Activity (HSA); (2) winter ionosphere anomaly feature, observed only in the northern hemisphere stations; and (3) daytime minimum and nighttime maximum in the diurnal structures of TEC at high latitude in the northern hemisphere during the winter. The nighttime maximum value was observed around 21:00 LT with magnitude that decreases with decrease in solar activity. The annual maximum value of TEC decreases with solar activity at all the stations, with the highest/lowest peak observed in HSA/LSA periods.
Comparative investigation of the digisonde‐derived electron density and iri profiles at a station near the african magnetic equator during low solar activity S. J. Adebiyi, J. O. Adeniyi, B. O. Adebesin, S. O. Ikubanni, I. A. Adimula, et al. Journal of Geophysical Research Space Physics, 2020 Information about the altitudinal distribution of ionospheric electron density (Ne) in the African equatorial region is very scanty. Such information is vital in modeling of key ionospheric parameters and in solving problems associated with ionospheric effect on the applications that depend on space‐based positioning and navigation systems. For the first time in the region, the entire Ne profile estimated by IRI is evaluated with profile deduced from Digisonde measurements at Ilorin (geog. 8.50°N, 4.50°E; dip. −7.9°) during low solar activity condition. Results obtained indicate marked discrepancies between the two profiles with magnitudes revealing local time and altitudinal and seasonal trends. The largest discrepancies are found between the post‐sunset and sunrise hours regardless of the seasons. IRI underestimates the Ne around the F1 region and is most obvious in September equinox and December solstice with deviation up to −42%. Further, IRI overestimates the Ne around the F2 peak at daytime, mostly in solstices with maximum deviation of 26% at F2 peak. All the three IRI topside models generally underestimate Ne between ~F2 peak height and ~800 km in all seasons except in June solstice. Beyond 800 km, the Digisonde, IRI‐NeQuick, and IRI‐2001 Corr profiles tend to converge, whereas the IRI‐2001 profiles still show marked divergence from the Digisonde profile in all seasons. Overall, the IRI‐NeQuick gives the best topside representation at this station at daytime/nighttime. The comparative analysis of Digisonde‐TEC and GPS‐TEC suggests that the Digisonde alone may not give a reliable estimate of the nighttime topside altitudinal distribution of Ne at this location.
Variations in raindrop size distribution and specific attenuation due to rain in Nigeria Annales Des Telecommunications Annals of Telecommunications, 1996
URSI-NG CONFERENCE 2021 ON THE FUTURE OF RADIO COMMUNICATION: PROSPECTS AND CHALLENGES IA Adimula, JS Ojo, ST Ogunjo, MO Ajewole, SE Falodun Journal of Physics: Conference Series 2021, 011001 , 2034 2034
Peer-Review Statements S Al Fatih, H Tegnan, HBMD Said, NR Yunus, A Saed, FJ Fernhout, ... Proceedings of the 6th International Conference on Law Reform (INCLAR 2025), 1 , 2025 2025
Proceedings of the 8th URSI-NG Annual Conference (URSI-NG 2024) I Adimula, J OJo, S Ogunjo Springer Nature , 2025 2025
Variation of Equatorial Estimated Vertical Ion Drifts During Low Solar Activity OE Ehinlafa, À GA, OA Oladipo, IA Adimula, JO Adeniyi Ilorin Journal of Science 11 (3 (Special)), 88-96 , 2024 2024
Quiet time Variation of the Geomagnetic H-component strength over Ilorin, North Central Nigeria KA Yusuf, IA Adimula, SA Bello Ilorin Journal of Science 11 (3 (Special)), 273-279 , 2024 2024
Vertical Plasma Drifts Estimated from Ionospheric F2-Region Real Heights at a Low Latitude Station during Low Solar Activity OE Ehinlafa, OK Onanuga, GA Àlàgbé, JO Adeniyi, IA Adimula, ... Ilorin Journal of Science 11 (1), 1-15 , 2024 2024
Occurrence pattern of large-scale ionospheric irregularities over Ilorin, Nigeria-During solar cycle 24 OA Oladipo, AO Olawepo, JO Adeniyi, IA Adimula, AA Willoughby, ... Journal of Atmospheric and Solar-Terrestrial Physics 248, 106092 , 2023 2023
Effect of geomagnetic storms on L-band scintillation over Ilorin, Nigeria OA Oladipo, AO Olawepo, JO Adeniyi, IA Adimula, AA Willoughby, ... Advances in Space Research 71 (11), 4587-4593 , 2023 2023 Citations: 2
Quiet-Day Variations of VLF Amplitude and Its Correlation with Meteorological Parameters M Oladipo, I Adimula AGU Fall Meeting Abstracts 2022, SH41C-03 , 2022 2022
Geomagnetic storms impact on post-sunset equatorial ionosphere at Ilorin during 2010 AO Olawepo, OA Oladipo, S Sodiq, O Odeyemi, BW Joshua, SJ Adebiyi, ... Geomagnetism and Aeronomy 62 (5), 632-651 , 2022 2022 Citations: 4
Current Understanding of the Equatorial E x B Drift velocities in the African Sector: A Short Review BO Adebesin, JO Adeniyi, IA Adimula, SJ Adebiyi, SO Ikubanni, ... Journal of the Nigerian Society of Physical Sciences, 54-58 , 2022 2022 Citations: 1
Implicit Three-Step Hybrid Block Method for Solving First Order Initial Value Problems in Ordinary Differential Equations W Barde, T Suleman, EE Dan, S Zando Caliphate Journal of Science and Technology 3 (2), 212-218 , 2021 2021
Synthesis and characterization of spin coated CZTS Thin films for solar cell applications AA Sifawa, A Shehu Caliphate Journal of Science and Technology 3 (2), 158-161 , 2021 2021 Citations: 2
Magnetic reconnections in a low and a high solar activity year GI Ojerheghan, IA Adimula Research Trends and Challenges in Physical Science Vol. 5, 72-91 , 2021 2021 Citations: 1
Characterization of seasonal and annual variation of horizontal component of magnetic field in africa and asia regions AO Idowu, IA Adimula, GI Ojerheghan Journal of Physics: Conference Series 2034 (1), 012011 , 2021 2021 Citations: 1
Science Forum (Journal of Pure and Applied Sciences) MO Oladipo, IA Adimula, A Olawepo SCIENCE FORUM (JOURNAL OF PURE AND APPLIED SCIENCES) 21, 562-567 , 2021 2021
Radio propagation and the 5G network in Africa IA Adimula, AO Idowu, GI Ojerheghan International Journal of Scientific Research and Engineering Development 3 … , 2020 2020 Citations: 3
Variations in equatorial electrojet current along the 210MM chain: A comparison of two approaches AO Idowu, IA Adimula, BO Adebesin International Journal of Physical Sciences 15 (3), 120-129 , 2020 2020
Characterization of Equatorial Electrojet Current in Africa Sector Using Two Approaches O Idowu, IA Adimula International Astronomy and Astrophysics Research Journal , 2020 2020 Citations: 1
Inter-hemispheric comparison of ionospheric TEC variation at each latitudinal band during quiet geomagnetic condition S Adebiyi, I Adimula, O Oladipo Journal of the Nigerian Society of Physical Sciences, 77-90 , 2020 2020 Citations: 4
MOST CITED SCHOLAR PUBLICATIONS
Rain attenuation statistics from rain cell diameters and heights GH Bryant, I Adimula, C Riva, G Brussaard International journal of satellite Communications 19 (3), 263-283 , 2001 2001 Citations: 115
Signature of the 29 March 2006 eclipse on the ionosphere over an equatorial station JO Adeniyi, SM Radicella, IA Adimula, AA Willoughby, OA Oladipo, ... Journal of Geophysical Research: Space Physics 112 (A6) , 2007 2007 Citations: 85
Variations in raindrop size distribution and specific attenuation due to rain in Nigeria IA Adimula, GO Ajayi Annals of Telecommunications 51 (1), 87-93 , 1996 1996 Citations: 63
Equatorial vertical plasma drift velocities and electron densities inferred from ground-based ionosonde measurements during low solar activity BO Adebesin, JO Adeniyi, IA Adimula, BW Reinisch Journal of Atmospheric and Solar-Terrestrial Physics 97, 58-64 , 2013 2013 Citations: 51
Ground magnetic effects of the equatorial electrojet simulated by the TIE‐GCM driven by TIMED satellite data Y Yamazaki, AD Richmond, A Maute, Q Wu, DA Ortland, A Yoshikawa, ... Journal of Geophysical Research: Space Physics 119 (4), 3150-3161 , 2014 2014 Citations: 48
A new index to monitor temporal and long-term variations of the equatorial electrojet by MAGDAS/CPMN real-time data: EE -Index T Uozumi, K Yumoto, K Kitamura, S Abe, Y Kakinami, M Shinohara, ... Earth, Planets and Space 60 (7), 785-790 , 2008 2008 Citations: 46
Assessment of IRI and IRI‐Plas models over the African equatorial and low‐latitude region SJ Adebiyi, IA Adimula, OA Oladipo, BW Joshua Journal of Geophysical Research: Space Physics 121 (7), 7287-7300 , 2016 2016 Citations: 37
GPS derived TEC and foF2 variability at an equatorial station and the performance of IRI-model SJ Adebiyi, OO Odeyemi, IA Adimula, OA Oladipo, SO Ikubanni, ... Advances in Space Research 54 (4), 565-575 , 2014 2014 Citations: 31
Variations of surface radio refractivity and radio refractive index gradients in the Sub-Sahel KC Igwe, IA Adimula The Nigerian Journal of Space Research (NJSR), Vol. 6, pp. 135-144 , 2009 2009 Citations: 30
Characterisation of GPS-TEC in the African equatorial and low latitude region and the regional evaluation of the IRI model SJ Adebiyi, IA Adimula, OA Oladipo Journal of Atmospheric and Solar-Terrestrial Physics 143, 53-70 , 2016 2016 Citations: 28
F2 layer characteristics and electrojet strength over an equatorial station BO Adebesin, JO Adeniyi, IA Adimula, BW Reinisch, K Yumoto Advances in Space Research 52 (5), 791-800 , 2013 2013 Citations: 27
Total electron content and magnetic field intensity over Ilorin, Nigeria OS Bolaji, JO Adeniyi, IA Adimula, SM Radicella, PH Doherty Journal of Atmospheric and Solar-Terrestrial Physics 98, 1-11 , 2013 2013 Citations: 25
Comparison between African equatorial station ground-based inferred vertical E× B drift, Jicamarca direct measured drift, and IRI model JO Adeniyi, BO Adebesin, IA Adimula, OA Oladipo, AO Olawepo, ... Advances in Space Research 54 (8), 1629-1641 , 2014 2014 Citations: 24
Low latitude nighttime ionospheric vertical E× B drifts at African region BO Adebesin, JO Adeniyi, IA Adimula, BW Reinisch Advances in Space Research 52 (12), 2226-2237 , 2013 2013 Citations: 24
Ionospheric response to magnetic activity at low and mid-latitude stations SJ Adebiyi, IA Adimula, OA Oladipo, BW Joshua, BO Adebesin, ... Acta Geophysica 62 (4), 973-989 , 2014 2014 Citations: 22
Ionospheric response to the storm-time disturbance of 29 May, 2010 BW Joshua, JO Adeniyi, IA Adimula, OA Oladipo, OA Olawepo, SJ Adebiyi Advances in Space Research 53 (2), 219-225 , 2014 2014 Citations: 22
Investigation on mid-latitude stations to storm-time variations of GPS-TEC SJ Adebiyi, IA Adimula, OA Oladipo Advances in Space Research 55 (5), 1339-1348 , 2015 2015 Citations: 20
Effects of aerosols loading in the atmosphere on the visibility changes in Ilorin, Nigeria IA Adimula, OA Falaiye, CL Adindu Centre Point Sci. Edit 16, 15-23 , 2008 2008 Citations: 20
Effects of rain on microwave and satellite communications in equatorial and tropical regions IA Adimula, OA Falaiye, AA Willoughby Nigerian Journal of Physics 17 (1), 66-71 , 2005 2005 Citations: 20
Simultaneous response of NmF2 and GPS-TEC to storm events at Ilorin BW Joshua, JO Adeniyi, OA Oladipo, PH Doherty, IA Adimula, ... Advances in Space Research 61 (12), 2904-2913 , 2018 2018 Citations: 19
