Analysis of Rainfall Regimes in Nigeria 1955-2014

Abstract

This work is on the analysis of rainfall regime in Nigeria.The study adopted the climate systems concept and the ex-post facto research design. Secondary data of rainfall for ground stations were collected from the Nigerian Meteorological Agency (NIMET) for the study, from 1955-2014 and data on sea surface temperature were collected from Institute of Oceanography and Marine Research. The stratified/random sampling technique was adopted for the study and six stations were selected based on the strata of the geo-politic zones that already exist in Nigeria. Analysis of Variance (ANOVA), independent t test, and Regression analysis were used for data analysis. Findings include, that, rainfall has a singular maxima in Nigeria; the decadal trends in rainfall of Nigeria showed that 1955-64 was the wetest period with average rainfall amount of 1500mm and the dryest period is 1985-94 with just over 1250mm average amount of  rain; furthermore, the study revealed that, there is a significant variation in the rainfall distribution in Nigeria at P>.000.  Again, climate of the two normal under review show some difference in characteristics (ie 1466.92mm >1372.91mm); the t model showed that climate change was significance at p>0.007; the regression model summary shows that, sea surface temperature, height above sea level, and latitude have a positive correlation (r, 0.87) with rainfall amount. And this relationship provides a 76.1% explanation of the rainfall pattern; and the regression model is significant at P>0.00, reflecting that rainfall amount in Nigeria significantly depends on sea surface temperature, height above sea level, and latitude.