The latent potential of restoration: Biophysical climate effects of land restoration in Africa

Land degradation is a globally recognised problem, decreasing food production, water availability, biodiversity and human welfare. As a reaction, several restoration initiatives have emerged that aim to reduce or reverse land degradation and its negative consequences. The increase in vegetation cover caused by land restoration projects can affect the regional and global climate, not only through carbon sequestration, but also by changing the biophysical properties of the earth's surface (e.g. albedo, surface roughness or evapotranspiration). Some land restoration initiatives explicitly focus on improving the regional climate through these biophysical processes. However, how these mechanisms apply to the often small-scale restoration projects remains uncertain. As a result, it is unknown how restoration through changes in vegetation can contribute to climate change adaptation. In this thesis, I aim to contribute to closing this gap by determining the biophysical climate effects of land restoration projects, focusing on Africa. Using remote sensing and atmospheric modelling, this thesis shows that land restoration projects in Africa can increase vegetation greenness, decrease the local surface temperature in semi-arid regions and increase cloud formation in West Africa, especially larger or clustered projects.