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, Redeemer’s University, Ede, Nigeria
2 Department of
Mathematical Sciences, Redeemer’s 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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Äëÿ öèòèðîâàíèÿ:
J. A. Falade, S.
O. Adesanya. The
Season and Diurnal Cycles of Surface Level Refractivity on
Electromagnetic Wave Path in Lagos, Nigeria.
Æóðíàë ðàäèîýëåêòðîíèêè [ýëåêòðîííûé æóðíàë]. 2018. ¹ 7.
Ðåæèì äîñòóïà: http://jre.cplire.ru/jre/jul18/7/text.pdf
DOI
10.30898/1684-1719.2018.7.7