Cutting an American family’s meat consumption by half is equivalent to getting rid of a car. Why isn’t the pressure on, asks Tim Benton.
The most recent figures for carbon dioxide levels in the atmosphere give one pause for thought. There was a bigger increase in CO2 in the atmosphere over the last year than had been recorded for many years; despite all we know, carbon is increasing faster than ever, and faster than imagined in IPCC’s ‘worst case’ scenarios.
In a meeting in late Spring, we were discussing what interventions could conceivably make a significant reduction in our personal carbon budgets that wouldn’t need a radical (and thus scary) lifestyle change. My thought was that by changing our consumption of meat we could have a surprisingly large impact.
‘Surprisingly’ because, although often discussed in foodie circles, it is not widely appreciated how much our meat consumption contributes to greenhouse-gas (GHG) emissions.
A top-down view of global emissions
Agriculture (including forestry and other land uses) is a very major component of our emissions. According to IPCC, global greenhouse gas emissions are 49Gt CO2e (i.e. methane and other greenhouse gases converted to equivalent units of CO2). Of these 14% are for the transport sector (that’s 6.86Gt), and 24% are for agriculture and forestry (and other land uses: so called AFOLU, so that’s 11.76Gt).
Deforestation for agriculture is a major source of GHG emissions.
Copyright: Jane Boles on Flickr
Looking at the transport sector’s emissions, in the US, 42% is due to domestic cars (EPA fastfacts data sheet: 787/1834mt), in the UK its 52% (64/123mt: DECC figures) and in the EU it’s about 41% (670/1650mt, EU data).
Car ownership is higher in the EU and North America than many parts of the world, so it is likely that somewhere less than 50% of global transport will come from cars (i.e. <3.43Gt). In contrast, livestock produce 7.1Gt of agriculture and forestry’s 11.76Gt. These figures are made up from methane from cow digestion (44%), land-use conversion to produce feed (27%) and 29% from cattle feed (grain, soya etc). Of this, about 4.6Gt CO2e is from cattle.
Thus, simply on a global basis, emissions from cattle probably exceed car emissions
Car for cow
Such a macro-analysis clearly has limitations. So, to get a feeling for this on a more personal basis, I looked up figures for the US – because I was asked to by someone who works in the US car industry.
USDA data, available online, shows that average American’s per capita annual meat consumption is 59lb beef, 48lb pork, 70lb chickens. A
recent paper suggests that the CO2e emissions per kg of meat are 32.15kg for beef, 3.91kg for poultry and 5.91kg for pork. (Another recent paper provides a similar estimate for beef at 31kg CO2e per kg meat.)
My way or the highway: reducing meat consumption is roughly equivalent to taking a car off the road. Copyright: David Kingham on Flickr
That suggests an average American’s meat consumption produces about 1.12 tonnes of carbon equivalents – the lion’s share of this is 862kg from beef.
Now let’s look at the data for domestic car use. According to US Federal Highway’s Agency, on average, each US car drives 12334 miles per year (19862km). A modern compact fuel efficient car is about 0.11kg CO2e per km. A two-car family would therefore, on average, emit about 4.37 tonnes of carbon from driving their 24668 miles. If that two-car family had four people in it (imagine parents and two teenagers), their meat emissions would be essentially the same at 4.44 tonnes.
Beef’s greenhouse gas footprint is very large (as Eshel’s paper highlights) because they are very inefficient at converting anything other than grass into meat. Increasingly, and especially in the US, demand for meat is leading to animals being fed concentrated food. On a global scale, enough calories to feed four billion humans is now being fed to livestock.
This concentrated diet turns beef cows into the resource-hungry SUVs of the livestock world.
Rearing cattle is an energy intensive and inefficient business.
Copyright: Taylorandayumi on Flickr
But in many parts of the world, livestock production is nutritionally, economically, socially or environmentally important. In the UK, for example, much less concentrated food is used, so the GHG emissions per kilo of meat are typically lower than in the US. So while the analysis above may be taken as a vegetarian agenda this is too blunt a conclusion.
The point is that all our consumption (whether for food, water, cars or other goods) requires energy, and by changing patterns of consumption we can change emissions. For the US analysis, a family eating half the meat could make the same GHG saving as getting rid of a car, and this may have less of an impact on lifestyle and therefore be easier to achieve.
The person for the US car industry ended up shouting at me down the phone: “My industry has been under enormous pressure to reduce GHG emissions, and every driver knows about the need for efficiency. Why isn’t the same pressure being put on me to change my diet?”
About Tim Benton
Tim Benton is GFS Champion and an interdisciplinary researcher working on issues around agriculture-environment interactions. Formerly, he was Research Dean in the Faculty of Biological Sciences, University of Leeds, and Chair of the Africa College Partnership, an interdisciplinary virtual research institute concerned with sustainable agriculture in sub-Saharan Africa. He has worked on the links between farming and biodiversity (and ecosystem services) for many years.