Comprehensive Analysis of Rainfall Variability in Urban Maiduguri, Nigeria: Implications for Climate Resilience and Sustainable Development

Abstract

Climate variability, including its effects on precipitation and atmospheric conditions, is a critical aspect of Earth’s dynamic climate system. The increasing frequency of extreme weather events worldwide necessitates a thorough understanding of climatic changes. To address the scarcity of localized climatic studies, this research focuses on Maiduguri, the capital of Borno State in northeastern Nigeria. This study aimed to assess the rainfall variability of urban Maiduguri, with the objectives of investigating rainfall patterns, examining trends, and evaluating variability. The study utilized 31 years of rainfall data from the Nigerian Meteorological Agency, spanning from 1992 to 2023. The data was statistically analyzed using the Coefficient of Variation, Rainfall Anomaly Index (RAI), Sen slope, and the Mann-Kendall trend test. The findings indicate that the minimum annual rainfall in Maiduguri is 292.7 mm, the maximum is 838.2 mm, and the mean annual rainfall is 519.34 mm. These values provide essential insights into the range and central tendency of Maiduguri’s annual rainfall, contributing to a comprehensive understanding of the region’s climatic conditions. Moreover, August stands out as the month with the highest mean value of 196.66 mm, indicating the peak of the rainy season. The Total Annual Rainfall Trend in Maiduguri shows a significant positive Sen’s Slope value obtained from the Mann-Kendall test (z-statistic = 2.773, p-value = 0.005), suggesting an increasing trend in monthly rainfall. The calculated Sen’s Slope of 172.000 highlights the peak rainfall during the core months of the rainy season. This indicates a moderate level of rainfall variability (CV = 28.3%), accompanied by notable fluctuations in the Rainfall Anomaly Index (RAI) during critical months. The Mann-Kendall trend test suggests potential shifts in precipitation patterns. This research serves as a foundation for informed decision-making by local authorities, urban planners, and environmental stakeholders.