An Estimate of Thermal Comfort in North-Central Region of Nigeria

Abstract

Heat Index describes the combined effects of temperature and humidity on human body. The Heat index expresses an apparent temperature felt by human body that cools slower at higher values of the relative humidity due to the reduction in the rate of evaporation .This study aimed at describing the comfort and discomfort periods caused by heat stress in some selected urban towns in five states of the North central region in Nigeria. Monthly data of Temperature, Relative Humidity and Wind speed for thirty years (1980-2009) obtained from Nigerian Meteorological Agency were used to calculate the Temperature-Humidity indices(THI) and Wind-chill index(WCI) for the five urban towns in North central region investigated. The results showed that severe heat stress were experienced in the months of April, May and March in descending order for Abuja, Minna, Lokoja and Bida while moderate heat stress were recorded in June, October, July, September and August for all these four towns where 50% of human and animals are not comfortable due to hot and humid weather condition. Remarkable, pleasant and comfortable sensations were observed throughout the year in Jos with exception of November, December and January which shows that 50% of inhabitants are partially comfortable due to cold and humid weather. The percentage frequency charts for all the five towns investigated were also presented in this study.