Pablo Looks at Carbon Footprint of Local Food

Pablo at Triplepundit wondered if worry about foodmiles was justified. Many point to a New Zealand study that found that "dairy and lamb production in New Zealand was more energy efficient than the British equivalent, even when the 12,000-mile trip to the UK was included." He notes:

"The macroeconomic concepts that drive globalization state that production of goods should occur in the country or region best suited to maximize the economic efficiency. But do these economic concepts take into account the impact of transportation? Probably not. The impact of transportation, primarily the climate change effects of the resulting greenhouses and security issues surrounding petroleum fuel, is typically externalized to society. That is, society pays for the poor environmental decision-making of the market."

So he looked at a bowl of cherries.

Let's look at an example. I am very confident about some calculations that I made on the production of Cherries. I used a cost study from UC Davis to determine the energy input versus the yield. I arrived at roughly 4.85 kg of CO2e (carbon dioxide equivalent units) for each kg of cherries. If we assume 500 km of transportation by semi we add 0.06 kg CO2e, or about 1.2%. If the same cherries are grown in Argentina and flown to the US (21,000 km) the emissions jump to 16.82 kg CO2e per kg of cherries, or 71.1%. Quite a difference!

He does point out that dried cherries transported by ship would have less impact because transport is so much more fuel efficient.

So, the impact of foodmiles depends on several factors:

* The distance transported.
* The transport mode.
* The concentration of the agricultural product (dehydrated or concentrated is better).
* The relative agricultural productivity and the amount of fertilizer required in each location.