Lake Chad is located at the south of the Sahara Desert in an arid region. The lake’s water resources are under severe pressure due to the basic needs of the growing population around the lake, global warming, and increasing irrigation demands. Numerous land cover change studies have measured the rate of depletion of the lake’s surface water. However, the contribution of the increasing high temperatures in the region which is also a compounding factor has received little attention. In this study, an assessment of the changes in surface water extent of Lake Chad from 1973-2017 was carried out through a land cover analysis. The potential influence of the rising land surface temperatures on the water losses was also studied. The extraction of the land cover was done using maximum likelihood classification. The results show that between 1973 and 1987, the lake lost 12,796.81km2 of its surface water area. This period coincided with a season of drought and dry seasons reported to have occurred in the lake’s area during the 1970s. Between 1987 and 2003, average temperature rise and change in surface water area was +1.54˚C and +962.71km2 respectively. Between 2003 and 2017, average temperature rise and change in surface water area was +3.69˚C and -25.17km2 respectively. These results provide further evidence of the alarming rate of water loss in the lake’s environment, and suggest a link between rising land surface temperatures and diminution of the lake’s water. The findings inform efforts directed at addressing the ecological problem facing the lake.

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This study analyzed the evaluation of wind resource potential available at Mubi and Gwoza Northeastern Nigeria; and Guider and Mokolo far North Cameroon stations, respectively selected in Mandara Mountains covering period of six years (2011 to 2016). At all stations the overall maximum mean annual wind speed of 2.82 m/s was found at Guider in 2015 and the minimum of 2.20 m/s at Gwoza in 2012. The occurrences of annual mean wind speed of 2.82m/s was observed in 2015 at Guider reflecting a higher Weibull shape of 10.44 and scale 2.96m/s parameter, respectively. They were respectively observed in 2012 in Gwaza as 2.20m/s, 6.34 and 2.36m/s, while others stations are moderate. The annual Wind Power Density (WPD) potential at all stations varies between 7.15 -14.25 W/m 2 while others are moderate. However, it was observed from this evaluation, that Mandara Mountain is a poor wind power potential site based on the International classification, with the highest value being Guider station. Therefore, the site is applicable for wind energy exploitation in small scale.