UNDERSTANDING RAINFALL VARIABILITY AS A BASIS FOR RESILIENT STRATEGIES IN OSOGBO, NIGERIA

Abstract

ABSTRACT Rainfall variability study is an essential factor in developing apt adaptation strategies against climate change in Osogbo, Nigeria. This study aimed to study the characteristics of rainfall variability in Osogbo and pin down an opportunity for future strategies that could help in combating and mitigating climate change impacts. The data for the analysis were collected directly from the secondary source. Rainfall data from the Nigerian Meteorological Agency (NiMet), the official source of climate data in the country. The analysis were divided into Time Series to identify trends; the Auto Regressive Integrated Moving Average (ARIMA) for forecasting, while seasonal analysis pointed to the presence of some seasonal anomalies. The weather in Osogbo was intensively conducive to rainfall for about seven months from April to October with a higher than usual volume in 2021 while its least value was in 2005 over this period. The ARIMA model supported the finding that the trend was very non-stationary (P value=0.6171) and prediction using model (1,1,1), showed an upward trend with fluctuations around 5.69mm. The Seasonal Analysis eventually indicated more rainfall in the dry, punctuated with fluctuations; while in the wet season, extreme events would take place. This study provided a glimpse into the rainfall trends and pattern evident in Osogbo and must thus draw important implications defining climate change adaptation strategies in and around this city. The study, therefore, recommended a climate-smart water management system for the city, framed under an adaptive coherence policy to increase climate adaptation.