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Large-scale climatic variability is seriously affecting rainfall and temperature distribution pattern in Sudano-Sahelian parts of Lake Chad Basin. The Kumadugu-gana and Yobe Rivers that drain the south-western part of the Lake Chad Basin now flow for six months only in a year instead of nine, and this has affected the entire ecosystem of the basin. This study examines the spatio-temporal variability of Kumagu-Yobe river basin rainfall. The study used monthly rainfall records for 1981-2017 from five different weather stations that spread across the up-and-downstream parts of the basin. To accomplish the objective of the study descriptive and inferential statistics were used in analyzing the rainfall attributes and temporal distribution pattern for each of the stations during the study period. Linear regression model was used in analyzing the stations rainfall temporal variability trend. The findings of the study revealed a large scale spatio-temporal variability in the distribution of the rainfall attributes during the study period. Generally, the basin recorded increasing trend of rainfall within the study period. Annual increasing trends of 1.1mm, 3.1mm, 17.6mm and 17.2mm were observed at Potiskum, Nguru, Bauchi and Kano stations respectively. Thus, Jos records insignificant decreasing trend of -0.2mm annually. Specifically, a variability of less than 1% was also observed at Jos and Potiskum stations which is statistically insignificant. A variability of 19%, 28% and 44% was observed at Nguru, Kano, Jos, and Bauchi respectively. Overall, throughout the study periods the basin recorded increasing trend of rainfall that is characterised with large scale fluctuations particularly at the upstream section of the basin.  However,  desertification and upstream water abstraction may have reduced any noticeable increase in stream downstream Keywords : River Yobe, Kumadugu-Yobe Basin, Rainfall, Spatio-Temporal variability   Copyright (c) 2022 Geosfera Indonesia and Department of Geography Education, University of Jember This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License

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The wetlands of the Kumadugu-Yobe River Basin are the economic mainstay of the lower and mid-stream basin population, providing a wide range of ecosystem services and functions. However, series of impediments have been altering the hydrology of the sub-basin wetlands since the early 1970s. In order to understand the extent of the impact of climate variability on the basin wetlands, this study mapped the temporal variability in wetland size from 1982–2018 and examined the wetland's response to rainfall and temperature variability. The study used advanced very high resolution spectroradiometer (AVHRS) and moderate-resolution imaging spectroradiometer (MODIS) NDVI data sets of 1982–2018 rainfall and temperature data from upstream and downstream stations. Geo-spatial technology and statistical tools were used in analysing the collected data. The findings reveal a large-scale annual increasing trend of 337km2 in wetland size between 1982 and 2018, as against the orthodox view of continuous degradation. The result of the analysis revealed that the wetland’s response to a 1% increase in downstream annual rainfall, upstream annual rainfall, Jos August rainfall and downstream temperature was by expanding by 5.2 km2, 7.5 km2, 33 km2 and shrinking by 1,456 km2, respectively. The study concluded that the basin wetlands respond significantly to any slide fluctuations in rainfall and temperature variables. Based on the findings, the research recommended proper water management strategies within the basin, especially in the Kano region. Water diversion into Tiga and Challawa dams from neighbouring basins is thus a key to the contentious existence of the basin wetlands.