Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria

Yusuf Babatunde Lawal; Joseph Babatunde Dada

doi:doi:10.11648/j.ajece.20230701.12

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Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria

Yusuf Babatunde Lawal, Joseph Babatunde Dada

Published in American Journal of Electrical and Computer Engineering (Volume 7, Issue 1)

Received: 15 April 2023 Accepted: 4 May 2023 Published: 10 June 2023

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Abstract

Variation in Surface Refractivity N is largely influenced by changes in some meteorological parameters such as air temperature, relative humidity, and pressure. These parameters are more accurate when measured locally due to their temporal and spatial variations. The research studies and verifies the contributions of the dry and wet term components of surface radio refractivity. The research focuses on the comparison of surface refractivity variations in two geoclimatic zones of Nigeria. The study reveals that the Sahel and Coastal zones have dissimilar distinct weather conditions and consequently diverse variational pattern of their surface refractivities diurnally and seasonally. The diurnal values of surface refractivity vary moderately on typical sunny days with average values of about 345-391 N-units and 275-314 N-units in the Coastal and Sahel respectively. Wider daily variations were observed during the rainy season in both geoclimatic zones due to frequent rainfalls, especially in the Coastal Stations. The average daily refractivity in the Coastal and Sahel during the rainy seasons are 339-390 and 311-384 N-units respectively. Analysis of the results obtained indicates that the annual mean of the ITU-R recommendation underestimates surface refractivity by 11-15% across the coastal stations and by 5-10% across the Sahel zone. The derived values for each station would be useful for radio engineers in the design and optimization of terrestrial radio links.

Published in	American Journal of Electrical and Computer Engineering (Volume 7, Issue 1)
DOI	10.11648/j.ajece.20230701.12
Page(s)	10-18
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Surface Refractivity, Geoclimatic Zones, Sahel Zone, Coastal Zone

References

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[3]	International Telecommunication Union, Radio Section (ITU-R), “Radio Refractive Index: its formula and refractivity data”, Rec. P 453-9, 2003.
[4]	Yusuf Babatunde Lawal and Emmanuel Temitope Omotoso, “Investigation of Point Refractivity Gradient and Geoclimatic Factor at 70 m Altitude in Yenagoa, Nigeria”, Journal of the Nigerian Society of Physical Sciences, Vol. 5, Issue 1, pp 1081, 2023, https://doi.org/10.46481/jnsps.2023.1081
[5]	International Telecommunication Union, Radio Section (ITU-R), “Radio Refractive Index: Its formula and refractivity data”, Rec. P. 453-11, pp. 8, 2015.
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[7]	Adewumi Oluwatoyin Ayo, Pius Adewale Owolawi and Joseph Sunday Ojo, "Performance of ARIMA modelling on sub-tropical rain attenuation at Ka-band terrestrial link in Kwazulu-Natal, South Africa," 2021 IEEE International Conference on Microwaves, Antennas, Communications and Electronic Systems (COMCAS), Tel Aviv, Israel, pp. 389-394, 2021, doi: 10.1109/COMCAS52219.2021.9629001.
[8]	Afullo T. J., Motsoela T., Molotsi D. F., “Refractivity gradient and k-factor in Botswana” Radio Africa, pp. 107-110, 1999.
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[12]	International Telecommunication Union, Radio Section (ITU-R), “Propagation data and prediction methods required for the design of terrestrial line-of-sight systems”, Rec. P. 530-15, pp. 2, 2013.
[13]	Igwe K. C and Adimula I. A, “Variation of Surface Radio Refractivity and Radio Refractivity Index Gradient in the sub-sahel”, Nigerian Journal of Space Research, Vol. 6, pp. 135- 144, 2009.
[14]	Okoro, O. N., and Agbo, G. A., “The effect of variation of meteorological parameters on the tropospheric radio refractivity for minna”, Global Journal of Science Frontier Research, Vol. 12, 1969.
[15]	Isikwue, B. C., Kwen Y. A and Chamegh T. M., “Variations in the tropospheric surface refractivity over Makurdi, Nigeria”, Research Journal of Earth and Planetary Sciences Vol. 3, Issue 2, pp. 50-59, 2013.
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[17]	Yusuf Babatunde Lawal, Joseph Sunday Ojo and Sunday Emmanuel Falodun, “Variability and Trends in Rain Height retrieved from GPM and implications on rain-induced attenuation over Nigeria”, Heliyon, Elsevier Ltd, Vol. 7, 2021, https://doi.org/10.1016/j.heliyon.2021.e08108
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APA Style

Yusuf Babatunde Lawal, Joseph Babatunde Dada. (2023). Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. American Journal of Electrical and Computer Engineering, 7(1), 10-18. https://doi.org/10.11648/j.ajece.20230701.12

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ACS Style

Yusuf Babatunde Lawal; Joseph Babatunde Dada. Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. Am. J. Electr. Comput. Eng. 2023, 7(1), 10-18. doi: 10.11648/j.ajece.20230701.12

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AMA Style

Yusuf Babatunde Lawal, Joseph Babatunde Dada. Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. Am J Electr Comput Eng. 2023;7(1):10-18. doi: 10.11648/j.ajece.20230701.12

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@article{10.11648/j.ajece.20230701.12,
  author = {Yusuf Babatunde Lawal and Joseph Babatunde Dada},
  title = {Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria},
  journal = {American Journal of Electrical and Computer Engineering},
  volume = {7},
  number = {1},
  pages = {10-18},
  doi = {10.11648/j.ajece.20230701.12},
  url = {https://doi.org/10.11648/j.ajece.20230701.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajece.20230701.12},
  abstract = {Variation in Surface Refractivity N is largely influenced by changes in some meteorological parameters such as air temperature, relative humidity, and pressure. These parameters are more accurate when measured locally due to their temporal and spatial variations. The research studies and verifies the contributions of the dry and wet term components of surface radio refractivity. The research focuses on the comparison of surface refractivity variations in two geoclimatic zones of Nigeria. The study reveals that the Sahel and Coastal zones have dissimilar distinct weather conditions and consequently diverse variational pattern of their surface refractivities diurnally and seasonally. The diurnal values of surface refractivity vary moderately on typical sunny days with average values of about 345-391 N-units and 275-314 N-units in the Coastal and Sahel respectively. Wider daily variations were observed during the rainy season in both geoclimatic zones due to frequent rainfalls, especially in the Coastal Stations. The average daily refractivity in the Coastal and Sahel during the rainy seasons are 339-390 and 311-384 N-units respectively. Analysis of the results obtained indicates that the annual mean of the ITU-R recommendation underestimates surface refractivity by 11-15% across the coastal stations and by 5-10% across the Sahel zone. The derived values for each station would be useful for radio engineers in the design and optimization of terrestrial radio links.},
 year = {2023}
}

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TY  - JOUR
T1  - Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria
AU  - Yusuf Babatunde Lawal
AU  - Joseph Babatunde Dada
Y1  - 2023/06/10
PY  - 2023
N1  - https://doi.org/10.11648/j.ajece.20230701.12
DO  - 10.11648/j.ajece.20230701.12
T2  - American Journal of Electrical and Computer Engineering
JF  - American Journal of Electrical and Computer Engineering
JO  - American Journal of Electrical and Computer Engineering
SP  - 10
EP  - 18
PB  - Science Publishing Group
SN  - 2640-0502
UR  - https://doi.org/10.11648/j.ajece.20230701.12
AB  - Variation in Surface Refractivity N is largely influenced by changes in some meteorological parameters such as air temperature, relative humidity, and pressure. These parameters are more accurate when measured locally due to their temporal and spatial variations. The research studies and verifies the contributions of the dry and wet term components of surface radio refractivity. The research focuses on the comparison of surface refractivity variations in two geoclimatic zones of Nigeria. The study reveals that the Sahel and Coastal zones have dissimilar distinct weather conditions and consequently diverse variational pattern of their surface refractivities diurnally and seasonally. The diurnal values of surface refractivity vary moderately on typical sunny days with average values of about 345-391 N-units and 275-314 N-units in the Coastal and Sahel respectively. Wider daily variations were observed during the rainy season in both geoclimatic zones due to frequent rainfalls, especially in the Coastal Stations. The average daily refractivity in the Coastal and Sahel during the rainy seasons are 339-390 and 311-384 N-units respectively. Analysis of the results obtained indicates that the annual mean of the ITU-R recommendation underestimates surface refractivity by 11-15% across the coastal stations and by 5-10% across the Sahel zone. The derived values for each station would be useful for radio engineers in the design and optimization of terrestrial radio links.
VL  - 7
IS  - 1
ER  -

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Author Information

Yusuf Babatunde Lawal

Department of Physics, University of Africa, Toru-Orua, Nigeria
Joseph Babatunde Dada

Department of Physical and Chemical Sciences, Elizade University, Ilara-Mokin, Nigeria

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APA Style

Yusuf Babatunde Lawal, Joseph Babatunde Dada. (2023). Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. American Journal of Electrical and Computer Engineering, 7(1), 10-18. https://doi.org/10.11648/j.ajece.20230701.12

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ACS Style

Yusuf Babatunde Lawal; Joseph Babatunde Dada. Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. Am. J. Electr. Comput. Eng. 2023, 7(1), 10-18. doi: 10.11648/j.ajece.20230701.12

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AMA Style

Yusuf Babatunde Lawal, Joseph Babatunde Dada. Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria. Am J Electr Comput Eng. 2023;7(1):10-18. doi: 10.11648/j.ajece.20230701.12

Copy | Download

@article{10.11648/j.ajece.20230701.12,
  author = {Yusuf Babatunde Lawal and Joseph Babatunde Dada},
  title = {Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria},
  journal = {American Journal of Electrical and Computer Engineering},
  volume = {7},
  number = {1},
  pages = {10-18},
  doi = {10.11648/j.ajece.20230701.12},
  url = {https://doi.org/10.11648/j.ajece.20230701.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajece.20230701.12},
  abstract = {Variation in Surface Refractivity N is largely influenced by changes in some meteorological parameters such as air temperature, relative humidity, and pressure. These parameters are more accurate when measured locally due to their temporal and spatial variations. The research studies and verifies the contributions of the dry and wet term components of surface radio refractivity. The research focuses on the comparison of surface refractivity variations in two geoclimatic zones of Nigeria. The study reveals that the Sahel and Coastal zones have dissimilar distinct weather conditions and consequently diverse variational pattern of their surface refractivities diurnally and seasonally. The diurnal values of surface refractivity vary moderately on typical sunny days with average values of about 345-391 N-units and 275-314 N-units in the Coastal and Sahel respectively. Wider daily variations were observed during the rainy season in both geoclimatic zones due to frequent rainfalls, especially in the Coastal Stations. The average daily refractivity in the Coastal and Sahel during the rainy seasons are 339-390 and 311-384 N-units respectively. Analysis of the results obtained indicates that the annual mean of the ITU-R recommendation underestimates surface refractivity by 11-15% across the coastal stations and by 5-10% across the Sahel zone. The derived values for each station would be useful for radio engineers in the design and optimization of terrestrial radio links.},
 year = {2023}
}

Copy | Download

TY  - JOUR
T1  - Comparative Analysis of Surface Refractivity Variations in the Sahel and Coastal Zones of Nigeria
AU  - Yusuf Babatunde Lawal
AU  - Joseph Babatunde Dada
Y1  - 2023/06/10
PY  - 2023
N1  - https://doi.org/10.11648/j.ajece.20230701.12
DO  - 10.11648/j.ajece.20230701.12
T2  - American Journal of Electrical and Computer Engineering
JF  - American Journal of Electrical and Computer Engineering
JO  - American Journal of Electrical and Computer Engineering
SP  - 10
EP  - 18
PB  - Science Publishing Group
SN  - 2640-0502
UR  - https://doi.org/10.11648/j.ajece.20230701.12
AB  - Variation in Surface Refractivity N is largely influenced by changes in some meteorological parameters such as air temperature, relative humidity, and pressure. These parameters are more accurate when measured locally due to their temporal and spatial variations. The research studies and verifies the contributions of the dry and wet term components of surface radio refractivity. The research focuses on the comparison of surface refractivity variations in two geoclimatic zones of Nigeria. The study reveals that the Sahel and Coastal zones have dissimilar distinct weather conditions and consequently diverse variational pattern of their surface refractivities diurnally and seasonally. The diurnal values of surface refractivity vary moderately on typical sunny days with average values of about 345-391 N-units and 275-314 N-units in the Coastal and Sahel respectively. Wider daily variations were observed during the rainy season in both geoclimatic zones due to frequent rainfalls, especially in the Coastal Stations. The average daily refractivity in the Coastal and Sahel during the rainy seasons are 339-390 and 311-384 N-units respectively. Analysis of the results obtained indicates that the annual mean of the ITU-R recommendation underestimates surface refractivity by 11-15% across the coastal stations and by 5-10% across the Sahel zone. The derived values for each station would be useful for radio engineers in the design and optimization of terrestrial radio links.
VL  - 7
IS  - 1
ER  -

Copy | Download