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.
This chapter provides an overview of the following:
- In what ways do food systems depend on the state of the environment and climate?
- How are these changing and what impacts of these changes on food systems have been observed so far?
- How will present and future changes affect food systems going forwards, and what will be the real-terms impacts of these effects for people?
- Food production depends on the availability of suitable land and soils, sunlight, water and pollinating insects, among other things; all of which are or will be affected in different ways by climatic and environmental change.
- There are many uncertainties surrounding how much and how fast global warming will take place, how this will translate into climatic changes in different locations, and consequently, how changes in climate will affect food systems
- Climate change is likely to have a mixture of positive and negative impacts on different parts of the food system, depending on the interplay between gradual temperature increase, extreme weather events, the CO2 fertilisation effect, changes in water availability, economic effects (e.g. trade), demographics and infrastructure.
- Negative impacts of climate change on crop production have already been observed – with some benefits also observed in high latitude regions. Impacts of climate change on terrestrial livestock have not been well-researched yet, but are expected to take place from heat and water stress on animals and animal feed.
- Separating the impacts of climate change on marine species from those of overfishing is difficult, but ocean acidification and sea temperature changes are likely to compound the negative effects of overfishing.
- Expectations of future crop yields depend strongly on modelling assumptions and the crop, but several models suggests that average crop yield decreases of more than 5% are more likely than not after 2050; and that in the tropics, negative yield impacts are very likely after the 2080s, regardless of which scenario is used.
- The challenge of meeting additional demands on food systems in the future from population growth and dietary change, will be exacerbated the effects of climate change on food production and will require adaptation action to reduce the level of impacts experienced.
- As well as production, post-harvest food systems activities are also likely to be impacted by climate change. These impacts may include disruption or changes to infrastructure, transport, imports, exports, and sourcing, as well increased risks of spoilage, waste and food-borne diseases.
- While some developed countries in the Northern Hemisphere are likely to experience some positive impacts of climate change on production in the first half of this century, many globally traded staple crops are grown in areas that will experience negative impacts with implications on global food security – especially in lower income countries, those that import food, and on poor farmers.
- A number of major crops have been shown to lose nutritional quality - at least in relation to zinc, iron and protein levels - at higher atmospheric CO2 levels, which may contribute to nutrient deficiencies in some countries, although these relationships are complex and uncertain.
Tara Garnet, FCRN, University of Oxford
Jess Finch, FCRN, University of Warwick;
Professor Tim Benton, Leeds University
Samuel Lee-Gammage, FCRN, University of Oxford;
Marie Persson, FCRN, University of Oxford;
Professor Mike Hamm, Michigan State University;
Dr Elin Röös, Swedish Agricultural University;
Dr Peter Scarborough, University of Oxford;
Dr Tim Hess, Cranfield University;
Professor Tim Key, University of Oxford;
Professor Tim Benton, University of Leeds;
Professor David Little, University of Stirling;
Professor Peter Smith, University of Aberdeen;
Mara Galeano Carraro.
Any inaccuracies and errors, remain the responsibility of the FCRN.
The production of this chapter was enabled by funding from the following sources:
The Daniel and Nina Carasso Foundation;
The Oxford Martin Programme on the Future of Food;
The Wellcome Trust;
The Esmée Fairbairn Foundation;
Waste Resources Action Programme (WRAP);
The Sustainable Consumption Institute at Manchester University.