Anna B. Harper , 1 , Tom Powell 2 , Peter M. Cox 1 , Joanna House 3 , Chris Huntingford 4 , Timothy M. Lenton 2 , Stephen Sitch 2 , Eleanor Burke 5 , Sarah E. Chadburn 1 , 6 , William J. Collins 7 , Edward Comyn-Platt 4 , Vassilis Daioglou 8 , 9 , Jonathan C. Doelman 8 , Garry Hayman 4 , Eddy Robertson 5 , Detlef van Vuuren 8 , 9 , Andy Wiltshire 5 , Christopher P. Webber 7 , Ana Bastos 10 , 11 , Lena Boysen 12 , Philippe Ciais 11 , Narayanappa Devaraju 11 , Atul K. Jain 13 , Andreas Krause 14 , Ben Poulter 15 , Shijie Shu 13
7 August 2018
Scenarios that limit global warming to below 2 °C by 2100 assume significant land-use change to support large-scale carbon dioxide (CO 2) removal from the atmosphere by afforestation/reforestation, avoided deforestation, and Biomass Energy with Carbon Capture and Storage (BECCS). The more ambitious mitigation scenarios require even greater land area for mitigation and/or earlier adoption of CO 2 removal strategies. Here we show that additional land-use change to meet a 1.5 °C climate change target could result in net losses of carbon from the land. The effectiveness of BECCS strongly depends on several assumptions related to the choice of biomass, the fate of initial above ground biomass, and the fossil-fuel emissions offset in the energy system. Depending on these factors, carbon removed from the atmosphere through BECCS could easily be offset by losses due to land-use change. If BECCS involves replacing high-carbon content ecosystems with crops, then forest-based mitigation could be more efficient for atmospheric CO 2 removal than BECCS.
Land-based mitigation for meeting the Paris climate target must consider the carbon cycle impacts of land-use change. Here the authors show that when bioenergy crops replace high carbon content ecosystems, forest-based mitigation could be more effective for CO 2 removal than bioenergy crops with carbon capture and storage.