" " ISSN 1684-1719, N 7, 2018

         DOI  10.30898/1684-1719.2018.7.7     (pdf)   

The Season and Diurnal Cycles of Surface Level Refractivity on Electromagnetic Wave Path in Lagos, Nigeria


J. A. Falade 1, S. O. Adesanya 2

1 Department of Physical Sciences, Redeemers University, Ede, Nigeria

2 Department of Mathematical Sciences, Redeemers University, Ede, Nigeria


The paper is received on June 6, 2018


Abstract. Data obtained from Nigerian Environmental Climatic Observing Program (NECOP) station located at the University of Lagos, Akoka were employed to study the variation of surface radio refractivity for Lagos. Attention were focused on seasonal variation because the diurnal variation though could be abrupt, but the period of occurrence is short compared to the seasonal variation of the surface refractivity. Most of communication equipment, particularly the digital systems, require short time to transmit information between base stations and mobile devices and also operate near the surface and their paths vary in matter of minutes due to the influence of weather conditions. Lagos is located in a coastal area and is vulnerable to weather fluctuation and hence, a good candidate for localized refractive index fluctuation. The diurnal profile is having the same pattern during the dry and the wet season and is high through the night and drops only slightly in the morning when sun rises to about 14:00h before it picks up slightly again round 16:00h when sun begins to set. The monthly graphs show the real time pattern of the other meteorological parameters and surface refractivity at a particular time of the year and thereby constitute the seasonal variation. The weather pattern and high rainfall in Lagos accounted for high surface radio refractivity throughout the year but goes low only, during the harmattan period which coincides with dry season. The diurnal refractivity distribution is a function of daily weather parameters, while the seasonal variation tilted towards the trends in the climatic conditions of Lagos.  

Keywords: Inter Tropical Discontinuity, Refractive Index, Coastal area, Radio path.


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J. A. Falade, S. O. Adesanya. The Season and Diurnal Cycles of Surface Level Refractivity on Electromagnetic Wave Path in Lagos, Nigeria. [ ]. 2018. 7. : http://jre.cplire.ru/jre/jul18/7/text.pdf

DOI 10.30898/1684-1719.2018.7.7