Anomalous Radio Propagation and Relative Incidence inTropical Zone

Adedayo Kayode David; Emmanuel Israel; Ojo Olusola Samuel

doi:doi:10.11648/j.ajaa.20180604.11

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Anomalous Radio Propagation and Relative Incidence inTropical Zone

Adedayo Kayode David, Emmanuel Israel, Ojo Olusola Samuel

Published in American Journal of Astronomy and Astrophysics (Volume 6, Issue 4)

Received: 16 January 2019 Accepted: 5 March 2019 Published: 22 March 2019

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Abstract

This paper investigate the percentage of anomalous occurrence in tropic region of West Africa using meteorological data obtained from Era interim archive. The data covered the period of 36 years span from 1979 to 2014. Refractivity gradient, G are calculated from meteorological parameters (temperature, relative humidity and pressure) via surface refractivity and refractivity at 100m above the sea level. Relative incidence, β_o, which percentage of time refractivity gradient at 100 m is less than -100 N-units/km were estimated from cumulative distribution of refractivity gradient. The result shows the occurrence of seasonal variation of refractivity gradient across the observed stations with high variability in Jos. Super refraction and ducting condition are prevalent in Akure and Lagos stations, whereas sub refraction and ducting conditions are predominant in Jos during the rainy and dry season respectively. Minimum values of relative incidence of about 10% and 78% at Akure and Lagos respectively were obtained around 12 noon. Highest relative incidence of 80%, 98% and 97% were obtained at Jos, Lagos and Akure respectively in the mid night. Positive correlation of 0.29 and 0.66 exist between surface refractivity and β_o in Lagos and Akure respectively, moreover negative correlation of -0.84 is observed in Jos.

Published in	American Journal of Astronomy and Astrophysics (Volume 6, Issue 4)
DOI	10.11648/j.ajaa.20180604.11
Page(s)	97-101
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

Anomalous, Propagation, Gradient

References

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[7]	Emmanuel I. and B. Adeyemi, “ Statistical Investigation of Clear Air Propagation in the Coastal and Plateau Regions of Nigeria,” Progress In Electromagnetics Research Letters, 64, 37-41, 2016.
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APA Style

Adedayo Kayode David, Emmanuel Israel, Ojo Olusola Samuel. (2019). Anomalous Radio Propagation and Relative Incidence inTropical Zone. American Journal of Astronomy and Astrophysics, 6(4), 97-101. https://doi.org/10.11648/j.ajaa.20180604.11

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ACS Style

Adedayo Kayode David; Emmanuel Israel; Ojo Olusola Samuel. Anomalous Radio Propagation and Relative Incidence inTropical Zone. Am. J. Astron. Astrophys. 2019, 6(4), 97-101. doi: 10.11648/j.ajaa.20180604.11

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AMA Style

Adedayo Kayode David, Emmanuel Israel, Ojo Olusola Samuel. Anomalous Radio Propagation and Relative Incidence inTropical Zone. Am J Astron Astrophys. 2019;6(4):97-101. doi: 10.11648/j.ajaa.20180604.11

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@article{10.11648/j.ajaa.20180604.11,
  author = {Adedayo Kayode David and Emmanuel Israel and Ojo Olusola Samuel},
  title = {Anomalous Radio Propagation and Relative Incidence inTropical Zone},
  journal = {American Journal of Astronomy and Astrophysics},
  volume = {6},
  number = {4},
  pages = {97-101},
  doi = {10.11648/j.ajaa.20180604.11},
  url = {https://doi.org/10.11648/j.ajaa.20180604.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaa.20180604.11},
  abstract = {This paper investigate the percentage of anomalous occurrence in tropic region of West Africa using meteorological data obtained from Era interim archive. The data covered the period of 36 years span from 1979 to 2014. Refractivity gradient, G are calculated from meteorological parameters (temperature, relative humidity and pressure) via surface refractivity and refractivity at 100m above the sea level. Relative incidence, βo, which percentage of time refractivity gradient at 100 m is less than -100 N-units/km were estimated from cumulative distribution of refractivity gradient. The result shows the occurrence of seasonal variation of refractivity gradient across the observed stations with high variability in Jos. Super refraction and ducting condition are prevalent in Akure and Lagos stations, whereas sub refraction and ducting conditions are predominant in Jos during the rainy and dry season respectively. Minimum values of relative incidence of about 10% and 78% at Akure and Lagos respectively were obtained around 12 noon. Highest relative incidence of 80%, 98% and 97% were obtained at Jos, Lagos and Akure respectively in the mid night. Positive correlation of 0.29 and 0.66 exist between surface refractivity and βo in Lagos and Akure respectively, moreover negative correlation of -0.84 is observed in Jos.},
 year = {2019}
}

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TY  - JOUR
T1  - Anomalous Radio Propagation and Relative Incidence inTropical Zone
AU  - Adedayo Kayode David
AU  - Emmanuel Israel
AU  - Ojo Olusola Samuel
Y1  - 2019/03/22
PY  - 2019
N1  - https://doi.org/10.11648/j.ajaa.20180604.11
DO  - 10.11648/j.ajaa.20180604.11
T2  - American Journal of Astronomy and Astrophysics
JF  - American Journal of Astronomy and Astrophysics
JO  - American Journal of Astronomy and Astrophysics
SP  - 97
EP  - 101
PB  - Science Publishing Group
SN  - 2376-4686
UR  - https://doi.org/10.11648/j.ajaa.20180604.11
AB  - This paper investigate the percentage of anomalous occurrence in tropic region of West Africa using meteorological data obtained from Era interim archive. The data covered the period of 36 years span from 1979 to 2014. Refractivity gradient, G are calculated from meteorological parameters (temperature, relative humidity and pressure) via surface refractivity and refractivity at 100m above the sea level. Relative incidence, βo, which percentage of time refractivity gradient at 100 m is less than -100 N-units/km were estimated from cumulative distribution of refractivity gradient. The result shows the occurrence of seasonal variation of refractivity gradient across the observed stations with high variability in Jos. Super refraction and ducting condition are prevalent in Akure and Lagos stations, whereas sub refraction and ducting conditions are predominant in Jos during the rainy and dry season respectively. Minimum values of relative incidence of about 10% and 78% at Akure and Lagos respectively were obtained around 12 noon. Highest relative incidence of 80%, 98% and 97% were obtained at Jos, Lagos and Akure respectively in the mid night. Positive correlation of 0.29 and 0.66 exist between surface refractivity and βo in Lagos and Akure respectively, moreover negative correlation of -0.84 is observed in Jos.
VL  - 6
IS  - 4
ER  -

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Author Information

Adedayo Kayode David

Department of Physics, Federal University of Technology, FUTA, Akure, Nigera
Emmanuel Israel

Department of Physics, Federal University of Technology, FUTA, Akure, Nigera
Ojo Olusola Samuel

Department of Physics, Federal University of Technology, FUTA, Akure, Nigera

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Plain Text BibTeX RIS

APA Style

Adedayo Kayode David, Emmanuel Israel, Ojo Olusola Samuel. (2019). Anomalous Radio Propagation and Relative Incidence inTropical Zone. American Journal of Astronomy and Astrophysics, 6(4), 97-101. https://doi.org/10.11648/j.ajaa.20180604.11

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ACS Style

Adedayo Kayode David; Emmanuel Israel; Ojo Olusola Samuel. Anomalous Radio Propagation and Relative Incidence inTropical Zone. Am. J. Astron. Astrophys. 2019, 6(4), 97-101. doi: 10.11648/j.ajaa.20180604.11

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AMA Style

Adedayo Kayode David, Emmanuel Israel, Ojo Olusola Samuel. Anomalous Radio Propagation and Relative Incidence inTropical Zone. Am J Astron Astrophys. 2019;6(4):97-101. doi: 10.11648/j.ajaa.20180604.11

Copy | Download

@article{10.11648/j.ajaa.20180604.11,
  author = {Adedayo Kayode David and Emmanuel Israel and Ojo Olusola Samuel},
  title = {Anomalous Radio Propagation and Relative Incidence inTropical Zone},
  journal = {American Journal of Astronomy and Astrophysics},
  volume = {6},
  number = {4},
  pages = {97-101},
  doi = {10.11648/j.ajaa.20180604.11},
  url = {https://doi.org/10.11648/j.ajaa.20180604.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaa.20180604.11},
  abstract = {This paper investigate the percentage of anomalous occurrence in tropic region of West Africa using meteorological data obtained from Era interim archive. The data covered the period of 36 years span from 1979 to 2014. Refractivity gradient, G are calculated from meteorological parameters (temperature, relative humidity and pressure) via surface refractivity and refractivity at 100m above the sea level. Relative incidence, βo, which percentage of time refractivity gradient at 100 m is less than -100 N-units/km were estimated from cumulative distribution of refractivity gradient. The result shows the occurrence of seasonal variation of refractivity gradient across the observed stations with high variability in Jos. Super refraction and ducting condition are prevalent in Akure and Lagos stations, whereas sub refraction and ducting conditions are predominant in Jos during the rainy and dry season respectively. Minimum values of relative incidence of about 10% and 78% at Akure and Lagos respectively were obtained around 12 noon. Highest relative incidence of 80%, 98% and 97% were obtained at Jos, Lagos and Akure respectively in the mid night. Positive correlation of 0.29 and 0.66 exist between surface refractivity and βo in Lagos and Akure respectively, moreover negative correlation of -0.84 is observed in Jos.},
 year = {2019}
}

Copy | Download

TY  - JOUR
T1  - Anomalous Radio Propagation and Relative Incidence inTropical Zone
AU  - Adedayo Kayode David
AU  - Emmanuel Israel
AU  - Ojo Olusola Samuel
Y1  - 2019/03/22
PY  - 2019
N1  - https://doi.org/10.11648/j.ajaa.20180604.11
DO  - 10.11648/j.ajaa.20180604.11
T2  - American Journal of Astronomy and Astrophysics
JF  - American Journal of Astronomy and Astrophysics
JO  - American Journal of Astronomy and Astrophysics
SP  - 97
EP  - 101
PB  - Science Publishing Group
SN  - 2376-4686
UR  - https://doi.org/10.11648/j.ajaa.20180604.11
AB  - This paper investigate the percentage of anomalous occurrence in tropic region of West Africa using meteorological data obtained from Era interim archive. The data covered the period of 36 years span from 1979 to 2014. Refractivity gradient, G are calculated from meteorological parameters (temperature, relative humidity and pressure) via surface refractivity and refractivity at 100m above the sea level. Relative incidence, βo, which percentage of time refractivity gradient at 100 m is less than -100 N-units/km were estimated from cumulative distribution of refractivity gradient. The result shows the occurrence of seasonal variation of refractivity gradient across the observed stations with high variability in Jos. Super refraction and ducting condition are prevalent in Akure and Lagos stations, whereas sub refraction and ducting conditions are predominant in Jos during the rainy and dry season respectively. Minimum values of relative incidence of about 10% and 78% at Akure and Lagos respectively were obtained around 12 noon. Highest relative incidence of 80%, 98% and 97% were obtained at Jos, Lagos and Akure respectively in the mid night. Positive correlation of 0.29 and 0.66 exist between surface refractivity and βo in Lagos and Akure respectively, moreover negative correlation of -0.84 is observed in Jos.
VL  - 6
IS  - 4
ER  -

Copy | Download