PAPER TITLE :ANALYSIS OF THE CORRELATION OF WATER VAPOUR PRESSURE WITH MICROWAVE RADIO REFRACTIVITY OVER AKURE, NIGERIA

JOURNAL Of SUSTAINABLE TECHNOLOGY | VOLUME 8 NUMBER 1 2017

Paper Details

  • Author(s) : ADEDIJI, A. T.
  • Abstract:

This paper examines the correlation of vertical profile of water vapour pressure with
that of the radio refractivity. The diurnal, seasonal and annual variations of water vapour pressure
and refractivity were computed and correlated from measured temperature, pressure and relative
humidity at the first 200 m height for a period of five years (2007-2011) over Akure (7.15oN,
5.12oE) Southwestern Nigeria. The measurements were taken round-the-clock at 30 minutes
interval using Davis 6162 Wireless Vantage Pro2 wireless weather station equipped with Integrated
Sensor Suite (ISS). The equipment was positioned on the ground surface up to a height of 200 m at
interval of 50 m on a television tower in Akure, Ondo State Nigeria. The results show that diurnal
variations of water vapour pressure have positive but weak linear correlation with refractivity at all
heights during the wet season months of the year implying a low degree of sensitivity of radio
refractivity to water vapour pressure during the wet seasons. On the contrary, very strong and
positive linear correlations of water vapour pressure with radio refractivity at all the heights were
observed for the dry season months; indicating that radio refractivity is very sensitive to water
vapour pressure during the dry seasons. The results also show very strong linear correlations for
seasonal and annual variations of water vapour pressure with radio refractivity at all the heights;
the implication is that refractivity is generally very sensitive to water vapour pressure.
Keywords: Microwave, Radio, Refractivity, Water vapour, Correlation