Could our meat-loving Western diets push climate change over the edge? That was the message of a recent report from UK think tank Chatham House that, even if the world moves away from fossil fuels, growth in meat and dairy consumption could still take global warming beyond the safe threshold of 2C.
The report recommends shifting away from this ‘four degree’ Western diet in favour of less meat- and emissions-intensive food.
What the evidence shows is that becoming vegetarian might help reduce your personal footprint—but it will be better to focus on a range of solutions if we want to have an impact on climate change.
How much greenhouse gas do livestock produce?
The most reliable and accepted estimate is that livestock production contributes about 14.5% of total greenhouse gases from people, mainly in the form of methane and nitrous oxide.
An ever-expanding number of studies, including many of our own at the Primary Industries Climate Challenges Centre, show that emissions from livestock are generally higher than from food crops, based on tonnes of greenhouse gas per unit area and mass of product.
However, it is important to note that, when compared on the basis of greenhouse gas per unit protein and per unit nutrient density, then some livestock products (such as cheese) become comparable with crops.
But could the predicted growth in consumption of livestock products make limiting global warming to 2C impossible? No.
Emissions will not necessarily rise in equal proportion to consumption, even without diet change. The world’s rising middle class is predicted to increase from 1.8 billion people to 3.2 billion by 2020 and to 4.9 billion by 2030.
Almost all of this growth (85%) will be in Asia where the increasing demand for animal-based protein is notably greater in white meat (fish, poultry, pigs) than red meat (cattle and sheep).
Thus the majority of the predicted future growth is in the lower-emitting livestock products. And waste could be used to generate energy, effectively bringing these industries close to carbon-neutral.
Vegetarianism isn’t for everyone
Most studies on the impact of changing diets remain theoretically-based and, to my knowledge, there has been no comprehensive global analysis of the political, ethical, moral and socio-economic challenges of changing diets across countries and cultures.
This is where the debate risks running aground: the privilege of choosing a vegetarian diet is limited to the affluent few, who, due to their declining birth rates, are a declining demographic. The majority of the world’s population remain more concerned about from where their next meal comes.
A focus solely on changing diet patterns runs the risk of becoming embroiled in the same moral arguments we’ve witnessed between the developing and developed economies on equitable greenhouse emission reduction targets and contributions to the Green Climate Fund.
Both these issues have stalled international climate negotiations, with the developed world (wealthy) being accused of dictating to the developing world (poor) that they cannot aspire to the same standard of living as has been enjoyed by the West while we created the climate change problem.
In the rather politically-charged debate on how to deal with climate change, the focus on vegetarianism as a solution to global warming also runs the risk of being dismissed as another line of attack for animal rights activists.
Don’t put all your eggs in one basket
Changing diets isn’t the only way to reduce greenhouse gas emissions from agriculture—and these alternatives are often missing in the commentary around meat-eating.
Few studies have reported, for example, on how diet moderation can be combined with clean energy generation from livestock waste, and greater research efforts into reducing methane produced by livestock.
Significant advances have already been made in reducing greenhouse gas emissions from livestock production systems including via livestock diets, breeding and inhibiting the microbes that produce methane.
There are now also well-established technologies for energy generation from livestock waste.
Compare this to the energy generation sector, where many studies have looked at combinations of solutions to reduce greenhouse has emissions, including reduced energy consumption, geo-sequestration, clean coal technologies and switching to alternative energy sources.
It is not the Western diet, but the Western lifestyle that is a ‘four-degree lifestyle’. The rest of the world cannot afford to converge around such levels of excess. We need a range of complementary solutions, rather than putting all our eggs in one basket.