International Peer-Reviewed JournalOpen AccessISSN 2456-8880
irejournals@gmail.com+91-7433024337

Home / Current Issue / Paper 1713231

1713231 Vol 9 · Issue 7 Download Paper

Morphology of M (3000) F2 At an African Equatorial Sector

Afolabi Peters Abiodun (Ph.D)

Subject area: Physical Sciences and Environment  ·  Area of research: Atmospheric Physics

DOI: https://doi.org/10.64388/IREV9I7-1713231

Abstract

This study examined the morphology of the ionospheric propagation factor M(3000)F2 over an African equatorial sector using long-term ionosonde observations from Korhogo, Ivory Coast. Existing published datasets covering the period from January 1993 to December 2000 were analyzed to investigate the diurnal, seasonal, and interannual characteristics of M(3000)F2. Hourly values were averaged to obtain monthly and seasonal mean profiles, and the data were classified into equinoctial and solstitial seasons to highlight systematic morphological patterns. The results showed that M(3000)F2 exhibited pronounced diurnal variability characterized by sharp post-sunrise maxima, extended daytime minima, prominent post-sunset enhancements, and sustained nighttime peaks across all seasons. Seasonally, higher M(3000)F2 values were consistently observed during the equinoxes compared to the solstices, indicating enhanced equatorial electrodynamic activity during equinoctial periods. Interannual analysis revealed that M(3000)F2 values were generally higher during years of low solar activity and reduced during years of elevated solar activity, although the fundamental diurnal structure remained largely invariant throughout the study period. These findings demonstrated that the morphology of M(3000)F2 at the African equatorial sector was primarily controlled by equatorial electrodynamic processes, including vertical plasma drifts and pre-reversal enhancement, with solar cycle conditions modulating the magnitude of variability. The study provided valuable observational evidence from a data-sparse region and contributed to improved understanding of equatorial ionospheric behavior relevant to high-frequency radio propagation and ionospheric modeling.

Keywords

M(3000)F2; Equatorial Ionosphere; Diurnal And Seasonal Variation; HF Radio Propagation; African Sector

References

[1] Abdu, M. A. (2016). Electrodynamics of ionospheric weather over the equatorial region. Journal of Atmospheric and Solar-Terrestrial Physics, 145, 1–21.

[2] Adebesin, B. O., Ikubanni, S. O., & Adebiyi, S. J. (2013). Assessment of the IRI model over the equatorial ionosphere using African ionosonde data. Advances in Space Research, 52(10), 1858–1867.

[3] Adeniyi, J. O. (1996). Magnetic storm effects on the morphology of the equatorial F2-layer. Journal of Atmospheric and Terrestrial Physics, 58(4), 445–455.

[4] Adeniyi, J. O., Oladipo, O. A., & Radicella, S. M. (2014). Diurnal and seasonal variations of ionospheric parameters at low latitudes. Advances in Space Research, 54(2), 255–265.

[5] Anderson, D. N., Anghel, A., Chau, J. L., & Veliz, O. (2004). Daytime vertical E×B drift velocities inferred from ground-based magnetometer observations at low latitudes. Space Weather, 2(11), S11001.

[6] Bilitza, D. (2018). Ionospheric models and data: A review. Advances in Space Research, 61(2), 273–287.

[7] Bilitza, D., Brown, S. A., Wang, M. Y., Souza, J. R., & Roddy, P. A. (2020). Measurements and modeling of the ionosphere. Advances in Space Research, 66(11), 2523–2541.

[8] Chapman, S. (1931). The absorption and dissociative or ionizing effect of monochromatic radiation in an atmosphere on a rotating Earth. Proceedings of the Physical Society, 43(1), 26–45.

[9] Danilov, A. D., & Lastovicka, J. (2012). Effects of solar activity variations on the ionosphere. Journal of Atmospheric and Solar-Terrestrial Physics, 81–82, 21–28.

[10] Davies, K. (1990). Ionospheric radio. Peter Peregrinus Ltd.

[11] Fejer, B. G., Scherliess, L., & de Paula, E. R. (1999). Effects of the vertical plasma drift velocity on the generation and evolution of equatorial spread F. Journal of Geophysical Research: Space Physics, 104(A9), 19859–19869.

[12] Kelley, M. C. (2009). The Earth’s ionosphere: Plasma physics and electrodynamics (2nd ed.). Academic Press.

[13] Liu, L., Wan, W., Ning, B., & Zhang, M. L. (2006). Climatology of the ionospheric F2-layer: Solar activity, seasonal, and latitudinal variations. Journal of Geophysical Research: Space Physics, 111(A8), A08304.

[14] Obrou, O. K., Adeniyi, J. O., & Oladipo, O. A. (2003). Diurnal and seasonal variations of the F2-layer over an equatorial station in West Africa. Journal of Atmospheric and Solar-Terrestrial Physics, 65(3), 359–368.

[15] Obrou, O. K., Zoundi, C., & Ouattara, F. (2009). Seasonal morphology of equatorial ionospheric parameters over West Africa. Advances in Space Research, 43(2), 281–289.

[16] Oyekola, O. S. (2013). Seasonal and solar cycle effects on ionospheric propagation parameters over Nigeria. Indian Journal of Radio & Space Physics, 42(5), 317–326.

[17] Rawer, K. (1993). Wave propagation in the ionosphere. Springer-Verlag.

[18] Rishbeth, H. (2000). The equatorial F-layer: Progress and puzzles. Annales Geophysicae, 18(7), 730–739.

[19] Rishbeth, H., & Mendillo, M. (2001). Patterns of F2-layer variability. Journal of Atmospheric and Solar-Terrestrial Physics, 63(15), 1661–1680.

[20] Stolle, C., Lühr, H., Fejer, B. G., & Koppmann, R. (2008). Seasonal and longitudinal variations of the equatorial electrojet. Journal of Geophysical Research: Space Physics, 113(A3), A03301.

[21] Tukhashvili, D., Kharshiladze, O., Jandieri, G., & Diasamidze, G. (2003). Modeling and prediction of the ionospheric propagation factor M(3000)F2 using regression techniques. Radio Science, 38(6), 1093.

[22] Zolesi, B., & Cander, L. R. (2014). Ionospheric prediction and forecasting. Springer.

How to cite this paper

Afolabi Peters Abiodun (Ph.D) "Morphology of M (3000) F2 At an African Equatorial Sector" Iconic Research And Engineering Journals Volume 9 Issue 7 2026 Page 93-101 https://doi.org/10.64388/IREV9I7-1713231
Afolabi Peters Abiodun (Ph.D) "Morphology of M (3000) F2 At an African Equatorial Sector" Iconic Research And Engineering Journals, vol. 9, no. 7, Jan. 2026, doi: https://doi.org/10.64388/IREV9I7-1713231
Afolabi Peters Abiodun (Ph.D) (2026). Morphology of M (3000) F2 At an African Equatorial Sector. Iconic Research And Engineering Journals, 9(7). doi: https://doi.org/10.64388/IREV9I7-1713231
Afolabi Peters Abiodun (Ph.D) "Morphology of M (3000) F2 At an African Equatorial Sector" Iconic Research And Engineering Journals, vol. 9, no. 7, Jan. 2026. Crossref, https://doi.org/10.64388/IREV9I7-1713231
@article{1713231,
      author = {Afolabi Peters Abiodun (Ph.D)},
      title = {Morphology of M (3000) F2 At an African Equatorial Sector},
      journal = {Iconic Research And Engineering Journals},
      year = {2026},
      volume = {9},
      number = {7},
      pages = {93-101},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1713231.pdf},
      abstract = {This study examined the morphology of the ionospheric propagation factor M(3000)F2 over an African equatorial sector using long-term ionosonde observations from Korhogo, Ivory Coast. Existing published datasets covering the period from January 1993 to December 2000 were analyzed to investigate the diurnal, seasonal, and interannual characteristics of M(3000)F2. Hourly values were averaged to obtain monthly and seasonal mean profiles, and the data were classified into equinoctial and solstitial seasons to highlight systematic morphological patterns. The results showed that M(3000)F2 exhibited pronounced diurnal variability characterized by sharp post-sunrise maxima, extended daytime minima, prominent post-sunset enhancements, and sustained nighttime peaks across all seasons. Seasonally, higher M(3000)F2 values were consistently observed during the equinoxes compared to the solstices, indicating enhanced equatorial electrodynamic activity during equinoctial periods. Interannual analysis revealed that M(3000)F2 values were generally higher during years of low solar activity and reduced during years of elevated solar activity, although the fundamental diurnal structure remained largely invariant throughout the study period. These findings demonstrated that the morphology of M(3000)F2 at the African equatorial sector was primarily controlled by equatorial electrodynamic processes, including vertical plasma drifts and pre-reversal enhancement, with solar cycle conditions modulating the magnitude of variability. The study provided valuable observational evidence from a data-sparse region and contributed to improved understanding of equatorial ionospheric behavior relevant to high-frequency radio propagation and ionospheric modeling.},
      keywords = {M(3000)F2; Equatorial Ionosphere; Diurnal And Seasonal Variation; HF Radio Propagation; African Sector},
      month = {January},
      doi = {https://doi.org/10.64388/IREV9I7-1713231}
  }