I recently had an Opinion Editorial published in The Age, with two co-authors, which discussed something most people don’t think a whole lot about – how their diet affects their carbon footprint. It was a response to the draft Garnaut Review on the economic impact of climate change on Australia. Here is a snippet.
PROFESSOR Ross Garnaut has managed to write a 548-report on climate change in which he mentions Australia’s largest current contribution to climate change precisely once — in the glossary, where we find a definition of “enteric fermentation”.
Never heard of it? It’s what goes on in the digestive systems of ruminants, like cattle and sheep. It produces methane, Australia’s largest but also most under-appreciated contribution to climate change over the next few decades. The second-largest current contribution is coal. It gets mentioned 272 times in the report — as it should.
Why is methane so under-appreciated? There’s a political reason and a technical reason.
The political reason is that if telling Australians that they need to pay more for petrol and electricity is tough, telling them they need to consume less beef, lamb and dairy products is going to be tougher still.
As for the technical reason, maybe the best way to explain it is like this: Suppose I offer you $1000 if you let me hold a blowtorch to your leg for 10 seconds. When you decline, I explain that you should not focus on just that 10 seconds when the torch is applied to your leg. I have calculated that the average temperature applied to your leg over the 20-minute period that starts when I apply the blowtorch, will be only 48 degrees, which is hot, but quite bearable.
That, in effect, is the approach Garnaut takes to methane in his draft report…
Continue reading here.
A more detailed overview, written for the layperson, is given in an Australasian Science article I published last year, which you can download for free. It shows that if you follow the recommended weekly dietary intake of beef, then your food will contribute more to global warming than if you also owned a large 4WD vehicle.
Of course, small things will amuse small minds…
Barry W. Brook