Measurement of Radio Refractive index in the first 100 m layer over Minna in North Central Nigeria

Abstract

Tropospheric radio refractivity at surface and 100m levels is investigated from in-situ measurement of atmospheric pressure, temperature and relative humidity made in Minna (9o 37’’N, 6o 30’’E), North central Nigeria. Daily measurement of the atmospheric variables was made at 30 minutes interval. The instrument used is the Vantage PRO II Automatic Weather Station and the data used was for a period of 12 months (January to December 2008). The results obtained show that the values of refractive index at both levels were high in the morning and late evening/night hours while the values were low during the afternoon hours. Also, statistical analysis of radio refractive index gradients was carried out