Roe et al., 2021
A recent study in Global Change Biology estimates the land-based mitigation potential (technical and cost-effective), related land footprints, mitigation density potential, and feasibility of 20 land and demand management activities for over 200 countries. The study developed and adapted 25 “bottom-up” sectoral databases and 6 integrated assessment models (IAMs), with new data including country estimates for agroforestry, biochar, peatlands soil carbon in agriculture, reduced food waste, and diet shifts.
The mitigation density per hectare indicates that the top 15 countries are smaller, mostly forested & coastal states: Maldives, Brunei, Bangladesh, Indonesia, Vietnam, Trinidad & Tobago, Malaysia, Malta, Rwanda, South Korea, Netherlands, Cambodia, Mauritius, Philippines, El Salvador. The protection of forests & other ecosystems and demand-side measures presented particularly high mitigation efficiency, high provision of co-benefits, and relatively lower costs. Peatlands, coastal wetlands and forests had the highest mitigation densities.
By providing comprehensive country-specifc data on mitigation activities and potentials, the study results offer countries an additional resource for updating national mitigation plans and enhancing ambition on nature-based solutions for COP26 and beyond. Compared to technical potentials, cost-effective estimates represent a more realistic and actionable target for policy.
Around 60% of cost-effective potential is found in the top 15 countries: Brazil, China, Indonesia, United States, India, Russian Federation, Canada, the Democratic Republic of the Congo (DRC), Colombia, Mexico, Argentina, Australia, Bolivia, Peru, and Myanmar. About a third of countries have cost-effective potential that are more than 50% of their total national emissions, and around 15% of countries have potential that exceeds all their emissions. A substantial portion of potential (80%) is in developing countries and LDCs, where feasibility barriers are of greatest concern
The study found that land-based nature-based solutions (NbS) measures could reduce 8-13.8 Gt CO2 equivalent per year between 2020 and 2050, and do this cost-effectively at less than $100 per ton of CO2 equivalent. The study found that approximately 20-30% of total mitigation is needed to limit warming to 1.5ºC.
The results indicate that assisting countries to overcome barriers may result in significant quantities of near-term, low-cost mitigation while locally achieving important climate adaptation and development benefits. Opportunities among countries vary widely depending on types of land-based measures available, their potential co-benefits and risks, and their feasibility. Enhanced investments and country-specific plans that accommodate this complexity are urgently needed to realize the large global potential from improved land stewardship, given that current levels of investments are inadequate in unlocking mitigation at the levels within the study.
Read the full paper ‘Land-based measures to mitigate climate change: Potential and feasibility by country’ in the journal Global Change Biology.Tweet