How food gets to our plates and what happens afterwards, connects many issues of concern, including health, biodiversity, climate change, livelihoods, and more. This chapter, and associated resources, provides an entry point into ‘food systems’ thinking and the multifaceted set of issues that are connected through food. It provides a foundation for the wider set of ideas and complexities that are explored in the other chapters of Foodsource.

It is an internationally agreed objective to cut human-caused greenhouse gas emissions to zero this century, to avoid the worst impacts of climate change. Given the major contribution of food system activities to total human-caused emissions, reducing these emissions is of great importance. But how and by how much can emissions be reduced, while also feeding a growing population? There are different perspectives on how food systems emissions can be reduced and it is helpful to explore these since these differences also underpin many other debates around food system sustainability. Understanding these perspectives helps to put specific proposals for reducing food system emissions into a wider food systems context.

Food systems are central to human well-being. We rely on them for nourishment, employment, livelihoods, culture and more. Reliable access to sufficient food is a foundation of human health, and of social and political stability. While the impacts of food systems on the environment are great, changes to the climate and the wider environment — to which food systems contribute — also have major implications for the functioning of food systems and all that they support. Understanding this matters, because sustainable food systems in the future must not only maintain human well-being with fewer environmental impacts, but must also be able to cope to different environmental conditions to those experienced today.

Emissions resulting from the many activities involved in food systems, account for a substantial portion of all human-caused greenhouse gas (GHG) emissions and, as such, contribute to climate change. A major challenge for the sustainability of food systems is, therefore to figure out how its contribution to GHGs can be reduced. If we are to be able to address and mitigate food systems’ contributions to climate change, it is important to understand where and how the greenhouse gas emissions arise across the whole food system. Also important, is to understand how different ways of organising parts of the food system, can result in differing levels of greenhouse gas emissions.