Relative benefits of allocating land to bioenergy crops and forests vary by region
Irina Melnikova, Philippe Ciais, Katsumasa Tanaka, Nicolas Vuichard, Oliviér Boucher
Abstract
Abstract Carbon dioxide removal is essential for achieving the Paris Agreement targets. Here we compare bioenergy with carbon capture and storage (BECCS) and afforestation and reforestation in terms of their carbon removal potentials and impacts on carbon cycle and surface climate under an overshoot pathway using Earth System Model simulations. Althought initially BECCS can remove more carbon in allocated areas, carbon dioxide emissions from land use change regionally offset the benefits of BECCS compared to afforestation, depending on the carbon capture and storage efficiency and timescales required to achieve mitigation targets. Furthermore, BECCS may cause local cooling in high- and mid-latitude subregions of the Northern Hemisphere dominated by albedo effects, while afforestation causes local cooling in subtropical and tropical subregions through non-radiative mechanisms. The decision to allocate land to bioenergy crops or forests should account for their respective carbon removal potentials, modulated by carbon-concentration and carbon-climate feedbacks, and the effects on climate.