Authors : Umar Alfa; Abubakar Haruna

Volume/Issue : Volume 8 - 2023, Issue 9 - September

Google Scholar : https://tinyurl.com/35r3bd42

Scribd : https://tinyurl.com/bdhy3k4w

DOI : https://doi.org/10.5281/zenodo.10016257

Abstract : Extreme rainfall events pose significant challenges to communities, infrastructure, and ecosystems in North Central Nigeria. This research investigates the characteristics and trends of extreme rainfall in the region to enhance our understanding of precipitation variability and its implications for flood risk management. A comprehensive literature review reveals the need for local-scale analysis, distribution fitting, climate change considerations, and community engagement in flood risk mitigation. Mann-Kendall trend tests are conducted across multiple locations (Ilorin, Minna, Jos, and Makurdi) and various time periods (daily, monthly, and annually) to assess significant trends in extreme rainfall. Results indicate a lack of statistically significant trends in daily and monthly rainfall for Ilorin, Jos, and Minna, suggesting the stationarity of the data. In contrast, both daily and monthly rainfall data for Minna and Makurdi exhibit significant upward trends, emphasizing the increasing intensity of rainfall events in these areas. Furthermore, the study applies the Generalized Extreme Value (GEV) distribution using different method (Maximum likelihood method, L-moment and Method of moment), the L-Moments method, to fit extreme rainfall data. The methodological approach demonstrates superior goodness-of-fit measures, supporting its preference for modeling extreme events in North Central Nigeria. The return level analysis based on the L-Moments method highlights increasing return levels with longer return periods, indicating a heightened potential for extreme precipitation. Return level estimates provide valuable insights for flood risk assessment and infrastructure planning.

Keywords : Precipitation, Time Series, North Central and Nigeria.