More on greenhouse gas from the US food system

Total greenhouse gas emissions associated with food production and distribution in the United States. The production phase accounted for 83% of emissions. (From Weber and Matthews 2008. Click image to go to source).

A 2008 study (830 KB pdf) from Carnegie-Mellon University, now freely available online, estimates that the production and distribution of food emits 8.1 metric tonnes of carbon dioxide equivalents per US household. That translates to 3.2 tonnes per person, or about 16% of US greenhouse gas emissions.

The study raises several interesting points:

1. The estimate that the food system accounts for 16% of greenhouse gas emissions is very similar to an estimate of 15% that I recently posted to this blog;
2. Eliminating red meat and dairy products from the diet for one day each week could have the same climate impact as buying all food locally for a year;
3. The average food item travels 4 times as far as the distance from the farm to the consumer. The average “farm to fork” distance in this study was 1,250 miles, but the food had to travel 5,120 miles to get there;
4. Even with all that travelling, transportation accounted for just 11% of food system greenhouse gas emissions.