Air temperature, relative humidity, climate regionalization and thermal comfort of Nigeria

Abstract

Planners and policy makers require information about the regions for which they are responsible. However, it seems that many developing countries, including Nigeria, are not adequately prepared either for their current climates or for the impact of climate change because they lack sufficient information. We have therefore examined the variations in the thermal condition in terms of the temperature, relative humidity, effective temperature (ET), temperature-humidity index (THI) and relative strain index (RSI). We studied the spatial and temporal (seasonal and monthly averages) variations in the thermal climate of Nigeria, and we divided Nigeria into thermal climate regions for effective climate change management. Mean annual minimum, mean and maximum temperatures (with their standard deviations) were 21.4 (3.5), 27.1 (2.7) and 32.8 (3.4) • C, respectively, while the overall mean relative humidity was 62 (24.8)%. Mean ET, THI and RSI were 24.3 (0.85), 24.8 (1.83) and 0.2 (0.18) • C, respectively. The ET, THI and RSI provided contrasting expressions of thermal comfort for Nigeria, because of its varied climate. We also found that elevation; the movement of the Inter Tropical Discontinuity and urbanization affect thermal comfort in Nigeria. We conclude that thermal stress has increased in Nigeria from 2000 at most stations, especially in the south and north-western regions, and that Nigerian thermal comfort climate is heterogeneous and requires analysis of multiple thermal indices.

A Perspective of the Diurnal Aspect of Thermal Comfort in Nigeria

“…The thermal comfort indices have been used in previous studies, and have been found to be suitable to the Nigerian (and tropical) climate [33] [34] [38] [39]. The 20 stations were selected to represent the different sub-climate types (tropical wet (TW), tropical wet and dry (TWD), guinea savanna (GS), sudan savanna, sahel savanna and montane) (Figure 2(a)).…”

“…Recent studies on the thermal comfort in Nigeria showed that the Nigerian thermal climate may not be well explained by a single thermal index, and therefore suggested the need for a multi-indices approach [33]- [39]. Other studies have also explored the seasonal and annual variations either at city, regional or country scale [33] [34] but information about the hourly variations is scarce.…”

A Temporal and Spatial Analysis of Urban Heat Island in Basin City Utilizing Remote Sensing Techniques

“…The similarities also lay in the effect of heat island between the edge areas of north-eastern and south-eastern mountains, embodying clear aggregation boundaries of high temperature. According to Eludoyin et al (2014), the population and social economic activities affects the spatial distribution of the cities, which is also revealed from the characteristics of the temporal and spatial changes. The temperature of heat island is increased due to the artificial development from 1990 to 2000.…”

GIS in the assessment of the impact of microclimatic variables on human comfort in Akure, Nigeria

“…The aim of any man is to be comfortable despite the climate, and this gives rise to the belief of thermal comfort (Eludoyin et al, 2013). Outside comfort zone lies the thermal stress (Ogunsote and Prucnal-Ogunsote, 2007).…”