ASSESSING THE SIGNIFICANCE OF METEOROLOGICAL PARAMETERS TO THE MAGNITUDE OF URBAN HEAT ISLAND (UHI)

An assessment of the relationship of UHI Intensity with wind speed, cloud cover and relative humidity was carried out in the city of Ibadan, Nigeria. Data on wind speed, relative humidity, cloud cover, minimum, maximum and mean temperature were sourced from six weather stations from 1993-2012. To enable proper extraction of climatic parameters and ensure adequate spatial coverage, eighteen-point locations were randomly selected by dividing the study area into 40 grid cells of 1 km × 1 km across the study area. The result of regression model showed that the independent variables account for only about 52.3% of the observed variation in UHI intensity, while the F-statistic indicates there was a significant relationship between the dependent and independent variables (= 8.806, P ≤ 0.05). It was further revealed that wind speed was found to be a significant predictor of UHI intensity with the latter weakening with increasing wind speed. Further analysis showed that at a critical wind speed of 7 m/h, UHI becomes unnoticeable. Relative humidity and cloud cover showed a negative and weak relationship with UHI Intensity. The study concluded that urban heat island intensity varies significantly and it is strongly influenced by meteorological parameters particularly wind speed. This study therefore recommends that more weather-monitoring stations and highly sensitive equipment for monitoring the climatic elements at regular intervals should be set up.