Analysis Of Rainfall Distribution In Owerri And Enugu, Nigeria Using Precipitation Concentration Index

Abstract

The precipitation concentration index (PCI) of Owerri and Enugu for 1974 to 2011 was computed to characterise the rainfall distribution for both locations. The PCI was estimated on an annual and seasonal scale. The seasonal estimation was based on the categorisation of the seasons in eastern Nigeria into long wet season, short wet season, short dry season and dry season. The results of the PCI computed for Owerri showed that 87% of the years for which annual PCI was computed fell within the moderate concentration category range, while for Enugu 71% of the years fell within the moderate concentration category. For the long wet season for the study period, 74% and 66% of the years fell within the uniform precipitation concentration category at Owerri and Enugu, respectively, while 13% of the years at Owerri, and 16% of the years at Enugu fell within the moderate precipitation category. The varying degrees of precipitation concentration as indicated by the study implies that effective management of water resources and agriculture, and the control of erosion in the study locations might be more difficult to achieve under the prevailing climatic conditions.

Key Words: Precipitation Concentration Index; Owerri, Enugu, Rainfall; Variability