F3: Local food
Research on food miles and food choices has concluded that transportation as a whole is only responsible for 11% of the life cycle emissions of US food, and transportation from producer to retail stores only accounts for about 4% of them. (It’s higher for fruits and vegetables, though. Estimates vary widely, from a couple of percent higher than the average to 40% or so. However, in general, most of the emissions associated with a typical American’s diet come from delivering stuff to the farm, fuel for machinery, emissions from fertilizer and pesticides, energy used in processing, and so on.) Local food has other benefits – it may well be fresher, and buying it may support the local economy, or small farming. It may also be that most local food is grown in ways that produce fewer emissions than industrial farming, but that depends. (One serious piece of research concludes that a 100% shift to organic food production in England and Wales would reduce local emissions, but raise overall emissions because an almost 40% reduction in productivity would have to be made up through additional land use elsewhere.)
In some situations, food from far away may well involve significantly higher emissions, though. (There are interesting discussions of this and all sorts of other everyday choices in Mike Berners-Lee’s How Bad Are Bananas: The Carbon Footprint of Practically Everything.)
Brighter Planet’s, “The American Carbon Footprint: Understanding and Reducing Your Food’s Impact on Climate Change“, says that all these supply chain food miles only produce 30% of the total emissions associated with our food; our trips to grocery stores and restaurants, which are 15% of a typical American’s transportation, produce the other 70% of them.
F3.1 Reduce purchases of food shipped by air
Perishable and relatively expensive food like asparagus, flowers out of season, fresh Alaskan salmon or fresh fish from Hawaii probably was flown in. (Bananas, on the other hand, come a long way, but by sea, which moves a ton of freight with 1/50th the emissions of a plane.)
F3.2 Reduce purchases of food grown or stored with high energy requirements
This all depends on the particular items. Canadian hothouse tomatoes may not travel that far to reach us, but heating the greenhouses takes energy which may or may not come from burning fossil fuel. In May or June, apples from Eastern Washington that have been stored all winter in refrigerated warehouses with high nitrogen levels may have a larger carbon footprint than fresh apples arriving from South America by boat.
F3.3 Community orchards