Analysis of Empirical Rainfall Data Covering 1979-2020 as a Guide to Agriculture and Water Resources Management in Ondo State, Nigeria

Abstract

The aim of this paper was to evaluate daily empirical rainfall data covering 1979-2020 as a guide to agriculture and water resources management in Ondo, State, Nigeria by collecting data from the Nigerian Meteorological Agency, Abuja, using various standard methods. Results showed that, the area observed rainfall throughout the year with March (86.4 mm) as the rainfall onset, November (56.4 mm) was the cessation, double maximum rainfall occurred in July (254.2 mm) and September (282.1 mm) with the climatological mean of 1752.2 mm. Also, the percentage (%) difference rainfall showed seven (7) positive and four (4) negative occurrences. The highest positive % difference occurred in September (10.4), while the lowest occurred in July (2.6). The highest negative % difference was -26.5 (November), while the lowest was -5.9 (August). The stations deviation from zonal average monthly rainfall showed that, Igbokoda, Ilaje LGA deviated in all the months negatively, while Okitipupa, Okitipupa LGA and Oka-Akoko, Akoko South West LGA deviated positively in eleven (11) months each. The study concluded that, rainfall varied and had declined generally over the study area. Hence, it was recommended that, the Seasonal Climate Prediction (SCP) by Nigerian Meteorological Agency (NiMet) should be down-scaled early to serve as a guide to farmers and hydrologists; irrigation should be encouraged; hybrid crops should be cultivated and more water reservoirs should be constructed.