Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/4058| DC Field | Value | Language |
|---|---|---|
| dc.contributor.authorall | Oyekola, O. S.; Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | en |
| dc.contributor.authorall | Oluwafemi, C. C.; Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | en |
| dc.date.accessioned | 2008-09-12T08:19:25Z | en |
| dc.date.available | 2008-09-12T08:19:25Z | en |
| dc.date.issued | 2007-10 | en |
| dc.identifier.uri | http://hdl.handle.net/2122/4058 | en |
| dc.description.abstract | F-region vertical velocities are derived from the ground-based ionosonde data for Ibadan (7.4°N, 3.9°E; dip 6°S: an equatorial station in the African zone), to study the general characteristics of electrodynamics of equatorial ionosphere, such as their variation with season, solar cycle, and magnetic activity at different local time sectors. The results show profound seasonal and geomagnetic effects. Except for equinoctial period, there is an excellent consistency in the magnitudes (nearly 20 m/s) and patterns of upward daytime F-region drifts at low and high solar activity periods. Evening F-region exhibits strong motion with absolute mean value for quiet-time (15 m/s) greater than on disturbed-time (10 m/s). The average downward quiet midnight-early morning hours sector value is well below than 10 m/s. The evening reversal time is earliest and latest during solstitial periods. Prereversal peak is season dependent and varies strongly with magnetic activity. We show that prereversal peak, daytime, and nighttime maximum drifts saturate at particular values of F10.7 cm solar radio flux index, effects not noticed with corresponding sunspot number. Our observations confirm several previous results from other equatorial sites utilizing different experimental techniques. | en |
| dc.language.iso | English | en |
| dc.relation.ispartof | Annals of Geophysics | en |
| dc.relation.ispartofseries | 5/50 (2007) | en |
| dc.subject | equatorial F-region | en |
| dc.subject | ionospheric variability | en |
| dc.subject | ionospheric modelling | en |
| dc.subject | ionosonde observations | en |
| dc.subject | ionospheric dynamics | en |
| dc.title | Morphology of F-region vertical E×B drifts in the African sector using ionosonde measurements | en |
| dc.type | article | en |
| dc.type.QualityControl | Peer-reviewed | en |
| dc.subject.INGV | 01. Atmosphere::01.02. Ionosphere::01.02.99. General or miscellaneous | en |
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YAMADA (1987): Simulation of ionospheric electric fields and geomagnetic field variation by the ionospheric dynamo for different solar activity, Ann. Geophysicae, 5A, 429-434. WOODMAN, R.F. (1970): Vertical drift velocities and eastwest electric fields at the magnetic equator, J. Geophys. Res., 75, 6249-6259. | en |
| dc.description.journalType | JCR Journal | en |
| dc.description.fulltext | open | en |
| dc.contributor.author | Oyekola, O. S. | en |
| dc.contributor.author | Oluwafemi, C. C. | en |
| dc.contributor.department | Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | en |
| dc.contributor.department | Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | en |
| item.openairetype | article | - |
| item.cerifentitytype | Publications | - |
| item.languageiso639-1 | en | - |
| item.grantfulltext | open | - |
| item.openairecristype | http://purl.org/coar/resource_type/c_18cf | - |
| item.fulltext | With Fulltext | - |
| crisitem.author.dept | Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | - |
| crisitem.author.dept | Department of Physics, College of Science and Technology, Covenant University, Canaanland, Ota, Ogun State, Nigeria | - |
| crisitem.classification.parent | 01. Atmosphere | - |
| Appears in Collections: | Annals of Geophysics | |
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| 03 Oyekola.pdf | 1.37 MB | Adobe PDF | View/Open |
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