Food’s Carbon Footprint
Not Easy To Measure
Jim Prevor’s Perishable Pundit, June 15, 2007
Before we in America acquire the British fascination with “food miles” — which we most recently discussed here when Richard Branson pointed out the impact of such a policy on Africa — we ought to look at what they are actually finding out in Britain as they look into the subject.
The African Channel picked up an article by The Sunday Telegraph that was headlined Locally Grown Food Has Higher Carbon Footprint Than Imported Products:
Conscientious consumers are being urged to buy locally sourced food in the battle against climate change. But, as Richard Gray discovers, produce from the other side of the world can actually have a smaller carbon footprint…
Already, the major supermarkets are crawling over each other to highlight their “locally sourced” produce, while Marks and Spencer has begun labeling air-freighted products with logos of aircraft. Yet some startling research is emerging that shows food miles might not be as bad as consumers have been led to believe….
Analysis of the industry reveals that for many foods, imported products are responsible for lower carbon dioxide emissions than the same foodstuffs produced in Britain. Even products shipped from the other side of the world emit fewer greenhouse gases than British equivalents.
The reasons are manifold. Sometimes it is because they require less fertiliser; sometimes, as with greenhouse crops, less energy; sometimes, as with much African produce, the farmers use little mechanised equipment. The findings are surprising environmental campaigners, who have, until now, used the distance travelled by food as the measure of how polluting it is.
One study by Lincoln University, in New Zealand, found that 2,849kg of carbon dioxide is produced for every tonne of lamb raised in Britain, while just 688kg of the gas is released with imported New Zealand lamb, even after it has travelled the 11,000 miles to Britain. Researchers and farmers in Britain have raised doubts over the accuracy of the New Zealand figures, but they concede that sheep farming in New Zealand is more efficient than in our own country.
“They have slightly better weather,” said Prof Gareth Edwards-Jones, from the department of agriculture at Bangor University, in Wales. “This means their grass can grow for longer and they don’t have to give their sheep as much feed as they do in the UK.
“With meat in the UK, there is also a supermarket issue. Each of the supermarkets runs its own abattoir, so if you sell your lamb to Tesco, you have to send your lamb to Tesco’s abattoir, even if you pass several local abattoirs on the way. As a result, the meat picks up a huge amount of ‘in-Britain’ food miles from farm to abattoir then to packaging before it gets to its final destination.
The style of farming in New Zealand is considered to be less intensive than in Britain because of the large areas of land. Mr McGaveston uses small amounts of hay to help supplement his sheep through the cold winter months and sends his lambs to be slaughtered and packaged at a plant just 40 miles away. Most of the electricity used is also supplied from a hydroelectric plant, which has minimal carbon dioxide emissions….
Dr Llorenç Milà I Canals, of Surrey University, said: “By May, apples harvested in Britain have been kept in refrigerated storage for more than six months, which uses a lot of energy. At that point, it becomes better to import from New Zealand.”
Earlier this year, Mr Williams revealed that growing roses in Kenya produces just 17 per cent as much carbon dioxide as growing them in Holland. Importing beans by air from Uganda or Kenya is also more efficient.
prof Edwards-Jones explained why: “In Uganda, they tend to have small farms that export beans. They don’t use tractors, as it is all done by hand, they use cow muck instead of fertiliser and don’t use hi-tech irrigation systems.”
For some products, however, it is better to buy British. British onions, for example, produce 14kg per tonne less CO2 than those imported from New Zealand….
Perhaps the key insight is this:
What is clear is that the so-called “carbon footprint” left by a product is a good deal more complicated than simply looking at the distance it has travelled. Food miles have become the villain in the environmental debate over the global food market, with campaigners counting every mile their organic blueberries and sugarsnap peas have travelled.
And for those who think that just a little better study will let us accurately judge these things, there is more news:
The disagreement over exactly how to measure the carbon footprint of food has lead to the Government stepping in. Last week, the Department for Environment, Food and Rural Affairs announced it was developing a standard carbon calculator that all manufacturers and retailers could use to label their products.
But a study by Bangor University, due to be completed this year, is set to complicate matters further. Researchers have found that the number of times a patch of soil is ploughed, and even the type of soil a vegetable is grown in, radically alters the amount of greenhouse gases released into the atmosphere.
In other words, this area is so complex it is probably impossible to reliably calculate. And the protectionists who are pushing this logic maybe should be wary of the outcome:
This could mean that clay soil in one part of the world may release more greenhouse gases than sandy soil elsewhere. Indeed, calculations of carbon dioxide emissions could also include the footprint left by employees involved in the production of food. Per capita carbon dioxide emissions in Britain are 9.2 tonnes, while for Kenya the figure is 0.2 tonnes and for Uganda it is 0.1 tonnes. By this method, importing from Africa would be far less environmentally damaging.
“Food miles” has nothing to do with the environment. It is just a marketing tool that supermarkets have latched onto in Britain. They should be ashamed of themselves for deceiving their customers into thinking they are doing something useful.