Assessing climate variability and its impacts on selected forest ecosystems in Taraba state: insights from the Mann-Kendall trend analysis of rainfall and temperature

Emmanuel Bulus¹, Bulus Luka Gadiga², Yohanna Peter², Philemon Headboy², and Hyellamada Samuel Jerry²

¹National Boundary Commission (NBC) No. 54,  Aguyi Ironsi Street, Maitama Abuja, Nigeria

²Department of Geography, Adamawa State University, Mubi

Abstract

This study examines climate variability and its effects on selected forest ecosystems in Taraba State, Nigeria, using Mann-Kendall trend analysis of rainfall and temperature data from 1991 to 2021. Climatic variables, including average monthly rainfall and mean minimum and maximum temperatures, were sourced from the Upper Benue River Basin Development Authority. The Mann-Kendall test was applied to assess trends, revealing slight upward trends in annual rainfall and maximum temperatures, and a subtle downward trend in minimum temperatures, although none were statistically significant. Hypothesis testing was conducted, with results suggesting no significant long-term trends in annual rainfall, maximum temperatures, or minimum temperatures over the study period. Specifically, for annual rainfall, the Mann-Kendall slope was 0.03 with a p-value of 0.96, indicating no significant trend. Similarly, for minimum and maximum temperatures, the Mann-Kendall slopes were -0.01 and 0.01, respectively, with p-values of 0.99, indicating no significant trends. It was recommended that strengthening monitoring efforts to track long-term climate trends accurately, utilizing advanced statistical techniques to discern meaningful patterns from natural variability among other recommendations.

Keywords

climate variability; Mann Kendall test; rainfall trends; temperature trends; forest ecosystems.

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