Assessment of Weather Parameters and Population Trends in Nnewi and Onitsha Nigeria

The increasing population affects weather and meteorological parameters through various mechanisms such as human activities, urbanization, and the production of excessive greenhouse gases (GHGs) through commercial products and industrialization. These changes have far-reaching effects on local and global climates, impacting ecosystems and human health. We studied the relationship between weather parameters and human population trends in Nnewi and Onitsha from 2010 to 2024. We carried out statistical analyses on the weather parameters and human population representing GHGs. In our study, we obtained results that show that increasing GHGs as defined by the increase in population adversely affects weather/metrological parameters. The yearly average temperature (T) increased from in 2010 to in for both Onitsha and Nnewi in 2024. Similarly, the yearly average dewpoint (DP) fell from to , the yearly average humidity (H) decreased from 86% to 70%, and the yearly average windspeed (WS) increased from to km/h from 2010 to 2024. The yearly average solar radiation (SR) increased from 170 W/m2 in 2010 to W/m2, and the yearly average UV index (UVI) from 6.0 in 2010 to 8.5 in 2024. The results of the correlation study indicate that the population positively correlates with T, WS, SR, and UVI, but negatively correlates with DP, H, and the amount of precipitation (PP). The magnitude of the slopes and intercepts of the linear fits to the scatter plots of the population and weather parameters were consistently higher in Nnewi than in Onitsha, indicating greater adverse effects in Nnewi than in Onitsha. In conclusion, this study revealed that increasing population (increasing GHG) affects metrological parameters and that Nnewi, an emerging populous city is showing signs of changes in weather and metrological parameters at a rate higher than that of Onitsha. This may result in serious adverse climatic conditions, and higher risks to public health, agriculture, and ecosystems due to increasing levels of GHGs.