Global potential for carbon sequestration: Geographical distribution, country risk and policy implications

We have provided a framework for identifying least-cost sites for afforestation and reforestation and deriving carbon sequestration cost curves at a global level in a scenario of limited information. Special attention is given to country risk in developing countries and the sensitivity to spatial datasets. Our model results suggest that within 20 years and considering a carbon price of US$50/tC, tree-planting activities could offset 1 year of global carbon emissions in the energy sector. However, if we account for country risk considerations-associated with political, economic and financial risks-carbon sequestration is reduced by approximately 60%. With respect to the geography of supply, illustrated by grid-scale maps, we find that most least-cost sites are located in regions of developing countries such as the Sub-Sahara, Southeast Brazil and Southeast Asia.