This paper was originally published in PNAS.
“Most nations recently agreed to hold global average temperature rise to well below 2 °C. We examine how much climate mitigation nature can contribute to this goal with a comprehensive analysis of “natural climate solutions” (NCS): 20 conservation, restoration, and/or improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We show that NCS can provide over one-third of the cost-effective climate mitigation needed between now and 2030 to stabilize warming to below 2 °C. Alongside aggressive fossil fuel emissions reductions, NCS offer a powerful set of options for nations to deliver on the Paris Climate Agreement while improving soil productivity, cleaning our air and water, and maintaining biodiversity.
Abstract: Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To address this, we identify and quantify “natural climate solutions” (NCS): 20 conservation, restoration, and improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands.
We find that the maximum potential of NCS—when constrained by food security, fiber security, and biodiversity conservation—is 23.8 petagrams of CO2 equivalent (PgCO2e) y−1 (95% CI 20.3–37.4). This is ≥30% higher than prior estimates, which did not include the full range of options and safeguards considered here. About half of this maximum (11.3 PgCO2e y−1) represents cost-effective climate mitigation, assuming the social cost of CO2 pollution is ≥100 USD MgCO2e−1 by 2030.
Natural climate solutions can provide 37% of cost-effective CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 °C. One-third of this cost-effective NCS mitigation can be delivered at or below 10 USD MgCO2−1. Most NCS actions—if effectively implemented—also offer water filtration, flood buffering, soil health, biodiversity habitat, and enhanced climate resilience. Work remains to better constrain uncertainty of NCS mitigation estimates. Nevertheless, existing knowledge reported here provides a robust basis for immediate global action to improve ecosystem stewardship as a major solution to climate change…”
Read on and access the full paper at: PNAS.
What are people saying about this study?
Christiana Figueres, convener of Mission 2020 and former head of the UN Framework Convention on Climate Change (UNFCCC): “Land use is a key sector where we can both reduce emissions and absorb carbon from the atmosphere. This new study shows how we can massively increase action on land use – in tandem with increased action on energy, transport, finance, industry and infrastructure – to put emissions on their downward trajectory by 2020. Natural climate solutions are vital to ensuring we achieve our ultimate objective of full decarbonisation and can simultaneously boost jobs and protect communities in developed and developing countries.”
Paul Polman, CEO Unilever: “Climate change threatens the production of food staples like corn, wheat, rice and soy by as much as a quarter – but a global population of nine billion by 2050 will need up to 50% more food. Fortunately, this research shows we have a huge opportunity to reshape our food and land use systems, putting them at the heart of delivering both the Paris Agreement on Climate Change and the Sustainable Development Goals.”
Lord Stern, Chair of the Grantham Research Institute: “Natural climate solutions are important not only for the climate but for the rural economy. In Australia, soil erosion has damaged about 70% of farmland, for example. If that soil is restored to full health, it can capture more carbon dioxide, and increase the amount of economically productive farmland. Similarly, forests are going to become hugely valuable as people become more aware of their vital role in absorbing carbon dioxide. That forests can, when well-managed, produce food and construction materials, and reduce flood risk also generates economic opportunities. This is why natural climate solutions are not about expensive government intervention against climate change. They are about jobs and investment opportunities in rural areas in every country on the planet.”
Roberto Rodrigues, former Ministry of Agriculture in Brazil, Coordinator of the Center for Agribusiness of Fundação Getúlio Vargas (FGV/EESP): “This new study confirms that a more productive and sustainable use of agricultural lands, in Brazil and across the world, besides increasing food supply for a growing population, can contribute substantially to a decrease of global warming gases. Both emerging and developed countries aiming to consolidate themselves as global leaders must act based on this new reality.”
Dr. Ibrahim MAYAKI, former Prime Minister of Niger, CEO of NEPAD (New Partnership for Africa’s Development): “Since COP 21 in December 2015 in Paris, the major role of agriculture and forestry to combat climate change has been clearly recognized. As developed countries put more emphasis on mitigation, developing countries try to adapt their agriculture to a changing world. This new study underlines the importance of nature, and especially trees and soils, as support for carbon sequestration through the cycle of plants based on photosynthesis. Promoting carbon sequestration in soils, with adapted agricultural and forestry practices, could lead to win-win solutions on mitigation, adaptation and increase of food security. Those are the triple objective of the “4 per 1000” Initiative already supported by 250 countries, organizations and institutions. We know what to do, now it’s time to act!”
Vidar Helgesen, Norway’s Minister of Climate and Environment: ”For many years natural climate solutions have moved up the agenda. We have seen some good leadership from tropical countries on avoiding deforestation. And the private sector is making progress in removing deforestation from commodity supply chains. Unfortunately this is not enough, and global deforestation continues at alarming rates. As the PNAS study shows, the climate opportunities in land use go beyond tropical countries. Deforestation has occurred all over the world, and degraded lands can be restored to support rural development. New approaches to farming can also cut emissions from that sector. We have the knowledge, and can achieve great things if we work across the public and private sectors, together with civil society.”
Dr. William H. Schlesinger, Professor Emeritus of Biogeochemistry and former president of the Cary Institute of Ecosystem Studies: “This study is the first attempt to estimate systematically the amount of carbon that might be sequestered from the atmosphere by various actions in forestry and agriculture, and by the preservation of natural lands which store carbon very efficiently. The results are provocative: first, because of the magnitude of potential carbon sequestration from nature, and second, because we need natural climate solutions in tandem with rapid fossil fuel emissions cuts to beat climate change.”
Carlton N. Owen, President & CEO, U.S. Endowment for Forestry and Communities: “This study points again to the important role that forests play not only in regulating Earth’s climate but the myriad other benefits they provide from drinking water to biodiversity to renewable and sustainable products to meet societal needs. Keeping existing forests as forests and reforesting marginal ag lands along with enhanced management practices on workings forests all have an important role to play in ensuring the health and vitality of the planet, its ecosystems, and its human inhabitants.”
