Embedding Nature-based Solutions into the social cost of carbon: a nationwide study in China

Keywords: Nature-based solution, social cost of carbon, socio-climatic scenarios, China
Abstract Type: Paper Abstract

Abstract

China, the world’s largest CO2 emitters, is making every effort to transition to a low-carbon economy and fulfill its part of a concerted global commitment to combating climate change. In tandem with decarbonizing energy and industries, feasible supplementary measures are urgently needed to help remove anthropogenic CO2 from the atmosphere. A promising option is Nature-based Solutions (NbS), which focuses on land re-naturalization, so as to remove CO2 from the atmosphere (via capture and storage) at relatively low costs. However, little empirical evidence exists concerning how various NbS alternatives and non-NbS land-use conversions (i.e., resulting in positive CO2 emission) could affect the social cost of carbon (SCC), a conventional measurement for prescribing carbon mitigation approaches. This study aims to fill in this knowledge gap via embedding NbS into the dynamic integrated climate-economics (RICE) model to quantify their impacts on the SCC. Using China’s land-use changes during 2000-2020, CO2 fluxes brought by different natural/semi-natural land conversions are quantified and feasible NbS interventions are specified. It is found that the SCC is mainly determined by energy and industrial structure, the overall effect of NbS is larger than the sum of land urbanization and non-NbS land-use conversion. Via embedding the real-world inter-dynamics of land-use conversions into the SCC quantification, this study presents a pioneer assessment of the impacts of NbS on the SCC in an integrated framework, sheds important insights into the effectiveness of NbS, and offers practical implications for policy-makers to devise comprehensive policies covering all feasible CO2 abatement options.