Carbon Dioxide Costs of Transporting Food

Environmental & Science Education, STEM, Sustainability, Global Change. Climate Change, Agriculture, Earth & Space Science. Earth Systems

Ed Hessler 

That we are an enormous expense to planet Earth is not news. We have much to learn about those expenses, including their size, meaning and implications. I suspect that we also don't know all of them.. Have you ever considered the costs of travel in transporting foods and production emissions?

Fortunately, Mengyu Li, a sustainability researcher at the University of Sydney (Australia) and her colleagues have. The research is reported on by Freda Kreier in the Nature News section for July 1, 2022 and is based on a research paper in Nature Food (linked behind a paywall) but you can learn about the team members as well as read the abstract).

"Transporting ingredients and food products accounts for nearly one-fifth of all carbon emissions in the food system," a larger amount than previously thought. And Kreier continues by noting that " Clearing land for farming, raising livestock and moving food to and from shops adds a large amount of greenhouse gas to the atmosphere. The United Nations estimates that growing, processing and packaging food accounts for one-third of all greenhouse-gas emissions."

Kreier reports  that "the complexity of the food system has made it challenging to measure" the greenhouse gas emissions at the system level. "Previously," she observes, "most studies underestimated emissions because they focused on only those generated by moving a single product - such as a chocolate bar - to and from the shop" and researcher Li told Kreier that this misses "the multitude of other trucks, ships and aeroplanes involved in gathering all the ingredients."

The report includes a nifty bar graph for a variety of food and industrial products, both for the domestic and international sides. It will come as no surprise that wealthy nations generate "nearly half of international food-transport emissions, despite accounting or only 12% of the global populations." There are reasons for this which are discussed.

Kreier interviewed Nina Domingo, a sustainability researcher at Yale University (New Haven) who told her that "the results don’t mean that people should try to limit the amount of plants in their diet." Continuing, Kreier writs that "many studies have shown that plant-based diets are better for the environment than consuming large amounts of red meat, because livestock need a lot of land and burp out greenhouse gases. Reducing the consumption of red meat and eating food produced locally could help wealthy countries to lower their climate impacts, researchers say."