Modelling of Extreme Rainfall Patterns in Accra‎

  • Authors

    • Esi Ahema Aboagye Department of Mathematics, Statistics & Actuarial Science, Takoradi Technical University, ‎Takoradi
    • Prof.Lewis Brew Department of Mathematical Sciences, University of Mines and Technology, Tarkwa
    • Dr. Benjamin Odoi Department of Mathematical Sciences, University of Mines and Technology, Tarkwa
    https://doi.org/10.14419/0c9qv646

    Received date: December 27, 2025

    Accepted date: February 5, 2026

    Published date: February 13, 2026

  • Block maxima; Climate change; Extreme rainfall; Fréchet Distribution; Return levels

  • Abstract

    Concerns about climate change and its possible impacts on human activities have increased the ‎awareness that climatic conditions are dynamic. West Africa, of which Ghana is part is one of the ‎areas in the world that had experienced major climatic anomalies in the past century. The purpose ‎of this research is to model rainfall data using block maxima approach of extreme value theorem. ‎Monthly rainfall data covering the period 1960 – 2022 were obtained from the Ghana ‎Meteorological Agency, Accra Airport substation. Statistical properties of the data indicated data ‎was stationary, however it was not normally distributed. Time series analysis of the data indicated ‎consistent increase in rainfall values with both downward and upward spikes indicating ‎fluctuations in the rainfall values. The Generalized Extreme value distribution was used to fit the ‎model of rainfall values. The rainfall values were fitted using the Generalized Extreme value ‎distribution. The Fréchet distribution was found to be the most appropriate model for the monthly ‎rainfall data. Additionally, it was discovered that the amplitude of the extreme values grows with ‎return periods, with higher return levels predicted to become more uncommon but severe over ‎time‎.

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  • How to Cite

    Aboagye, E. A. ., Brew, P. ., & Odoi, D. B. . (2026). Modelling of Extreme Rainfall Patterns in Accra‎. International Journal of Basic and Applied Sciences, 15(2), 7-14. https://doi.org/10.14419/0c9qv646