Land-based measures to mitigate climate change: Potential and feasibility by country
Stephanie Roe, Charlotte Streck, Robert Beach, Jonah Busch, Melissa Chapman, Vassilis Daioglou, Andre Deppermann, Jonathan Doelman, Jeremy Emmet-Booth, Jens Engelmann, Oliver Fricko, Chad Frischmann, Jason Funk, Giacomo Grassi, Bronson Griscom, Petr Havlik, Steef Hanssen, Florian Humpenöder, David Landholm, Guy Lomax, Johannes Lehmann, Leah Mesnildrey, Gert-Jan Nabuurs, Alexander Popp, Charlotte Rivard, Jonathan Sanderman, Brent Sohngen, Pete Smith, Elke Stehfest, Dominic Woolf, Deborah Lawrence
Abstract
Land- based climate mitigation measures have gained significant attention and im-portance in public and private sector climate policies. Building on previous studies, we refine and update the mitigation potentials for 20 land- based measures in >200 countries and five regions, comparing “bottom-up” sectoral estimates with inte-grated assessment models (IAMs). We also assess implementation feasibility at the country level. Cost-effective (available up to $100/tCO2eq) land- based mitigation is 8– 13.8 GtCO2eq yr−1 between 2020 and 2050, with the bottom end of this range representing the IAM median and the upper end representing the sectoral estimate. The cost-effective sectoral estimate is about 40% of available technical potential and is in line with achieving a 1.5°C pathway in 2050. Compared to technical potentials, cost- effective estimates represent a more realistic and actionable target for policy. The cost-effective potential is approximately 50% from forests and other ecosystems, 35% from agriculture, and 15% from demand-side measures. The potential varies sixfold across the five regions assessed (0.75–4.8 GtCO2eq yr−1) and the top 15 countries account for about 60% of the global potential. Protection of forests and other ecosystems and demand-side measures present particularly high mitigation efficiency, high provision of co- benefits, and relatively lower costs. The feasibility assessment suggests that governance, economic investment, and socio- cultural conditions influence the likelihood that land- based mitigation potentials are realized. A substantial portion of potential (80%) is in developing countries and LDCs, where feasibility barriers are of greatest concern. 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.