Document Type : Original Article


1 Department of Mathematics and Computer Science, Edo State University Uzairue, Nigeria

2 Department of Statistics, University of Benin, Benin City, Edo State, Nigeria


This paper focuses on the interdependence between rainfall and temperature and their joint effect. Rainfall and temperature are vital climatic variables for agricultural productivity and other human activities. Despite the importance of rainfall and temperature, there are difficulties associated with accurate analysis of their joint distribution due to the possibility of interrelationship between the variables. Several studies have been conducted by researchers on the interaction between climatic variables in order to ascertain their effects on the environment because temperatures are observed to be undergoing changes regularly. The analysis of rainfall and temperature for exploratory and visualization purposes is investigated because underlying structures and patterns do form the basis of decisions by government and regulatory agencies. This study employs the statistical approach in investigating the interdependence between rainfall and temperature in Ekpoma, Edo State, Nigeria for a period of five consecutive years from 2016 to 2020 using the Gaussian kernel estimator. The results of the investigations using some statistical indicators establish that there is irregular pattern of rainfall which is occasioned by changes in temperature. The variability of rainfall is mostly prominent in two years which are 2017 and 2019 with 29.43mm and 27.74mm as maximum amount of rainfall respectively. The results also demonstrate that the performance of years with high standard deviations are better than that of low standard deviations. Again, the performance of years with high negative correlation coefficients and high negative covariance of rainfall and temperature is better than years with weak correlations and low covariance.


Main Subjects

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