Variability of meteorological factors on surface refractive index over Mowe, a coastal area in Nigeria

Abstract

Radio climatology is an important factor in understanding radio wave propagation particularly in the troposphere where time varying properties due to weather conditions are prevalent. Therefore, the diurnal and seasonal variations of surface radio refractivity for Mowe (06°E, 52°N) via Lagos in South-West Nigeria are studied. Particular emphasis is laid on diurnal variations of the surface refractivity, which is high through the night and drops sharply just before sunrise and starts to pick up slightly around 14:00 to 15:00 hrs LT. It drops to minimum around 16:00 hrs LT before it increases again. The sinusoidal patterns of plots are obtained for temperature, relative humidity and refractivity. The patterns of the profile obtained are attributed to the oscillatory movement of inter-tropical discontinuity (ITD), which largely dictate the condition of weather and account for high rainfall in the coastal region where the study is undertaken. The results show that surface radio refractivity, generally, has higher value during the rainy season than dry season, which partly coincide with the harmattan period.