Where are the best opportunities for reducing greenhouse gas emissions in the food system (including the food chain)? A comment

In a recent paper Garnett (2011) examines the greenhouse gas emissions arising from the global food system. This paper builds on Garnett's contribution by considering how high levels of food waste contribute to the food chain's greenhouse emissions and how they can be reduced, something Garnett generally overlooks. The emissions that arise from food waste represent the emissions embedded in the production of food that is then wasted and the emissions that arise from the process of waste disposal. Food waste can also be split into pre-consumer and consumer waste. These distinctions give rise to four categories of food waste related emissions: pre-consumer embedded, pre-consumer waste disposal, consumer embedded and consumer waste disposal emissions. The levels of food waste in each category differ between economies, as do the causes of wastage. Policies to address food waste and the associated emissions need to promote a mixture of technological and behavioural change and be tailored to the economic, cultural and technological conditions in each country.

► We identify four different categories of emissions arising from food waste. ► The relative importance of these categories differs around the world. ► Reducing food wastage can substantially reduce food system GHG emissions. ► Different waste management techniques can reduce emissions from food waste disposal. ► A range of policy options can reduce waste and waste management emissions.