Abstract:
West Africa is undergoing rapid agricultural intensification driven by population growth, leading
to significant anthropogenic land use and land cover change (LCC), including both deforestation
and afforestation. These changes can profoundly affect the regional climate system by altering the
surface energy balance, moisture fluxes, and atmospheric circulation, potentially exacerbating the
vulnerability of human, ecological, and economic systems. Despite the ability of climate models to
simulate LCC impacts, considerable uncertainties remain, particularly in simulations of
precipitation and temperature responses. This study provides the first multidisciplinary systematic
review of LCC impacts in West Africa. Data from 26 selected publications were eventually
synthesized from an initial pool of nearly 6000 studies. Results indicate that deforestation generally
contributes to regional warming, with significant historical temperature increases of
+0.26 ± 0.12 ◦C and projected increases of +0.88 ± 0.25 ◦C under the future scenarios.
Conversely, afforestation could have significantly cooled the climate, lowering temperatures by
−0.24 ± 0.14 ◦C historically and −0.22 ± 0.14 ◦C in future scenarios, without even accounting for
carbon sequestration. Deforestation decreases regional precipitation by 80 ± 58 mm yr−1
historically and −55 ± 102 mm yr−1 in future scenarios, while large-scale afforestation could
substantially reduce droughts with increased precipitation, averaging +40 ± 67 mm yr−1
historically and 80 ± 58 mm yr−1 in future scenarios. These results emphasize the need to integrate
LCC-induced climate effects into land-based mitigation strategies, climate policy, and assessment
frameworks.
Description:
A Publication submitted to the West African Science Service Centre on Climate Change and Adapted Land Use and the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana, in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Climate Change and Land Use
