A Preliminary Investigation into the Annual Rainfall Trend and Patterns for Selected Towns in Parts of South-Eastern Nigeria

Abstract

Thirty – five (35) years (1971-2006) annual rainfall figures from three towns in Humid South-eastern Nigeria have been analysed for climatological baseline pattern and trend. Rainfall is choosen based on its importance while Calabar, Uyo and Umuiahia have synoptic stations with standard instruments and trained personnel hence reliable data. Rainfall is characteristically Humid with very high annual totals and ranges etc. There is statistically significant association of the baseline descriptive parameters and the region (x²_c > x²_t = 3759.96 > 16.8) at 99% confidence. No particularly clear fluctuating patterns or periodicities but trend analysis with the least square regression model suggest significantly declining trends for Uyo and Umuiahia. And  have been statistically modeled for predictive and scientific  management purposes as; Y = 3191.23 – 36.16x + e and; Y = 2955.20 – 31.50x + e respectively. Annual rainfall projections up to year 2015 have been carried out while further studies with urbanization and transportation as well as potential impacts in the area are suggested.