Climate Change Responses Benefit from a Global Food System Approach

Feb 18, 2020


A paper released today by the journal Nature Food presents a new global food system approach to climate change research that brings together agricultural production, supply chains, and consumption. When these activities are considered together, they represent 21 to 37 percent of total human-caused greenhouse gas emissions, the paper notes. It says that this new approach also enables a fuller assessment of the vulnerability of the global food system to increasing droughts, intensifying heatwaves, heavier downpours, and exacerbated coastal flooding. Food system responses thus play a major role in both adapting to and mitigating climate change, the authors assert.

The authors of the paper – including Cynthia Rosenzweig, AgMIP Executive Committee Member and Erik Mencos Contreras, AgMIP Project Coordinator – worked together on the Food Security chapter of the recent Intergovernmental Panel on Climate Change Special Report on Climate Change and Land. They represent a wide range of food systems from around the world, from major commodity and livestock producers to smallholder farming systems.

The paper explains that modeling and ex ante simulations of adaptation and mitigation, such as done by AgMIP, can present solutions for how to avoid competition between climate change mitigation and food security, as well as illustrate the potential barriers to implement specific practices.

“The global food system approach represents a significant advance in helping producers and consumers plan effective and well-integrated climate change responses,” said Cynthia Rosenzweig, the lead author and head of the Climate Impacts Group at the NASA Goddard Institute for Space Studies and Columbia University’s Center for Climate Systems Research.

“This approach brings into focus the emissions from all relevant food system activities, both within and outside the farm gate. In doing so, it breaks down the artificial separation between agriculture and related land use activities, such as deforestation, in country reports to the U.N. Climate Convention,” said Francesco Tubiello, co-author of the paper and a senior U.N. Food and Agriculture Organization officer. Concurrent with the paper, FAO is releasing today new emission statistics for the period 1990-2017 that provide the shares of agriculture and related land use in total emissions from all economic sectors, for all countries.

“The food system approach helps countries identify and implement context-specific responses on adaptation and mitigation,” said Cheikh Mbow, co-author and director of Future Africa. “It provides a better framework for addressing sustainable development and climate challenges.”

“Diversification of the food system by establishing integrated production systems and broad-based genetic resources can reduce risks from climate change,” said Murukesan Krishnapillai, co-author and research scientist with the College of Micronesia-FSM. “This is particularly important for smallholder farmers, who are among the most vulnerable to the effects of climate change,” added Erik Mencos Contreras, co-author and staff associate at Columbia University’s Center for Climate Systems Research, where AgMIP is headquartered.

To respond to climate change via their food systems, countries can now move beyond supply-side mitigation in crop and livestock production, which has been the traditional approach, to encompass demand side strategies, including dietary changes.

Plant-based diets reduce the amount of methane emissions, a powerful greenhouse gas released by ruminants. They also require less land, thus sparing areas that can be used to plant trees and store more carbon. When both these effects are combined, the maximum amount of greenhouse gas reduction achievable through dietary change is up to 8 billion tonnes of CO2e per year, say the authors (total anthropogenic emissions are currently about 52 billion tonnes per year).

Healthy and low-emission diets that are primarily plant-based can also reduce the burden of key non-communicable diseases, such as heart disease and diabetes, say the authors.

“Reducing food loss and waste from across the entire food chain can now be considered as well, which can lead to opportunities for food systems to engage in the circular economy,” said Mario Herrero, co-author and chief research scientist of agriculture and food at Australia’s Commonwealth Scientific and Industrial Research Organisation.

“This approach reveals several synergies in response options across food systems, bringing co-benefits to livelihoods and biodiversity. And in this way, these responses also help to achieve the Sustainable Development Goals,” said Prajal Pradhan, co-author and agro-ecologist at Germany’s Potsdam Institute for Climate Impact Research. “For example, increasing soil organic matter can help sequester carbon and enhance resilience to drought, as well as boost productivity and soil biodiversity”. 

Access the paper, here: and here (read-only version):