Shipping vs Airfreight revisited: Some more considerations

The environment blog over at New Scientist has just revisited the shipping versus airfreight debate that we covered here. Just to refresh your memories, this was a story that the Guardian reported on, claiming that shipping produces 2.5 times the amount of emissions that airlines create. Interestingly, New Scientist takes a slightly different angle on why aviation is getting so much stick, while shipping remains relatively untouched by protests. Aside from the fact that aviation is set to grow faster than shipping, NS also points out that the aviation industry is easier to pressure than the shipping industry. While many airlines are recognized high-profile brands, it’s a fairly safe bet that most consumers could not name too many freight ship operators or manufacturers.

However, this leaves aside a big question, touched on in our comments section, regarding emissions by weight of cargo e.g. if the same amount of freight was shipped by air or by sea, which would produce more greenhouse gases? It seems, looking at the numbers, that shipping comes way ahead of airlines on this count. When this author was working out a carbon offset scheme for a previous employer, using Climate Care's calculations, shipping 1.5 tonnes of product by ship to the UK created 0.124 tonnes of CO2, while shipping only 0.5 tonnes of the same product by air created 4.5 tonnes of CO2. So, while John’s original recommendation to buy local in his post still stands, if it is a question between shipping cargo by ship or by plane, then it looks like the ship wins every time, at least if these numbers are to be believed.
One interesting concept on all this is the FEET index (The Foreign Exchange Earnings per Transport ton of CO2 ) that was produced by Bioregional Development Group as a means of balancing trade as a development tool versus greenhouse gas emissions. It basically argued that foreign trade was fine, but that you should measure goods by a combination of how much co2 they emit in shipping, versus how much economic benefit they brought to the producer countries – high value, non-perishable goods like wine, craft items etc that could be shipped by sea came out very well. Software and intellectual property came out extremely well. Tourism sucked. Cheap bulk commodities like wood and charcoal sucked. We've been unable to find many details on the FEET index online, but it is featured in the book, Bioregional Solutions for Living on One Planet.