Eating locally produced foods can reduce transport emissions
A lot of focus has been placed on reducing greenhouse gas emissions by limiting the production and consumption of livestock animals. However, a recent study led by scientists from the University of Sydney has shown that the transport of food in general is responsible for a massive three gigatons of emissions annually, which is equivalent to almost 20 percent of all food-related emissions.
The study, published today in the journal Nature Food, suggests that the emissions resulting from transporting foodstuffs are up to seven times higher than previously estimated, and also far exceed the emissions caused by transporting other commodities. For example, transport accounts for only seven percent of industry and utilities emissions. The authors emphasize that there is an urgent need to reduce transport emissions and therefore consumers should focus on eating locally-produced foods.
“Our study estimates that global food systems, due to transport, production, and land use change, contribute about 30 percent of total human-produced greenhouse gas emissions. So, food transport – at around six percent – is a sizeable proportion of overall emissions,” explained study lead author Dr. Mengyu Li. “Food transport emissions add up to nearly half of direct emissions from road vehicles.”
“Prior to our study, most of the attention in sustainable food research has been on the high emissions associated with animal-derived foods, compared with plants. Our study shows that, in addition to shifting towards a plant-based diet, eating locally is ideal, especially in affluent countries,” said co-author Professor David Raubenheimer.
The researchers analyzed the emissions from transporting various goods in 37 different economic sectors, such as vegetables and fruit, livestock, coal and manufactured items. They considered the transport emissions resulting from both domestic and international transport, both within the producing country and within the country to which the goods were exported. They accounted for both the distances travelled and the masses of goods transported.
The findings revealed that rich countries contribute disproportionately to the emissions resulting from transporting foodstuffs. The United States, India, and Russia are the top food transport emitters, overall, but high-income countries in general contribute more to these emissions. For example, wealthy countries such as the United States, Germany, France, and Japan constitute 12.5 percent of the world’s population yet generate nearly half (46 percent) of food transport emissions.
Australia was found to be the second largest exporter of food transport emissions, given the breadth and volume of its primary production. Transport emissions are also food-type dependent. With fruit and vegetables, for example, transport generates nearly twice the amount of emissions as production. This is partly due to the fact that they require temperature-controlled transportation in order to ensure they arrive at their destination in fresh condition. The transport of fruit and vegetables contributes over a third of all food transport emissions.
The authors suggest that consumers need to choose locally produced foods that are in season, rather than out-of-season foods that need to be transported from a distance. They calculate that if the global population ate as ‘locavores’ (people who only eat food grown or produced within a 100-mile (161km) radius), this would reduce food transport emissions by 0.38 gigatons, an amount that is equivalent to emissions generated from driving one ton to the Sun and back, 6,000 times.
Although the authors acknowledge this scenario is not realistic because many regions cannot be self-sufficient in food supply, they say there are things that richer countries can do to reduce their food transport emissions. These include using cleaner energy vehicles and encouraging businesses to use production and distribution methods that reduce emissions.
Also, according to co-author Professor Manfred Lenzen, there is considerable potential for peri-urban agriculture to nourish urban residents. “Both investors and governments can help by creating environments that foster sustainable food supply,” Professor Lenzen said.
In addition, the attitude of consumers is of paramount importance. Supply of foods is driven by demand, meaning that the consumer has the ultimate power to change this situation. “Changing consumers’ attitudes and behavior towards sustainable diets can reap environmental benefits on the grandest scale,” said Professor Raubenheimer.
“One example is the habit of consumers in affluent countries demanding unseasonal foods year-round, which need to be transported from elsewhere. Eating local, seasonal alternatives, as we have throughout most of the history of our species, will help provide a healthy planet for future generations.”
The term “locavore” was the Oxford Word of the Year in 2007. Now, 15 years later, the researchers of the current study highlight its relevance again. More than ever, the consumers of the world need to recognize the inappropriateness of choosing to eat foods from the far-flung corners of the Earth.
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By Alison Bosman, Earth.com Staff Writer
