Changing global diets could yield biggest cuts in carbon emissions from farming, say scientists
Cows grazing on a ranch in Brazil, the world’s largest beef exporter (Pic: Valerio Pillar/Flickr)
By Gerard Wynn
Cutting meat consumption could large enormous cuts in carbon emissions while avoiding substantial lifestyle changes in target countries, according to a new study.
World meat consumption is growing in line with rising income and population in emerging and developing countries.
But livestock production also has a large carbon footprint, accounting for 50 to 70% of direct agricultural greenhouse gas emissions, according to Friday’s report, “Strategies for Mitigating Climate Change in Agriculture”.
Reducing meat consumptions receives little research attention, perhaps unsurprisingly given the political difficulty of prescribing people’s diets.
Friday’s report suggested that, in addition, advocacy and civil society groups were focused on improving food security, meaning that the issue of changing diets slipped through the cracks.
“Reducing demand of meat by a relatively small amount would have a significant absolute impact on greenhouse gas emissions, human health and the environment associated with livestock production,” found the report, published on Friday by the research groups Climate Focus and California Environmental Associates.
The report used an illustrative “healthy diet” of 90 grams of protein per day.
Data from the UN’s Food and Agriculture Organisation shows that of 174 countries, only 47 nations had diets which exceeded this level of protein intake in the years 2005-2007.
But diets in emerging economies are changing rapidly, meaning that most countries would exceed the threshold in coming decades, if they do not already.
Global adoption of such a diet would cut greenhouse gas emissions by an estimated 2.15 billion tonnes of carbon dioxide equivalent annually in 2030, the report estimated. Present fossil fuel CO2 emissions are 35 billion tonnes annually.
Growing problem
Greenhouse gas emissions from agriculture include both indirect emissions, for example in the manufacture of fertiliser, and direct emissions.
Combined, these account for about a fifth of global greenhouse gases, equivalent to the transport sector, underlining why agriculture cannot be ignored.
Regarding direct emissions, methane from ruminants, especially cattle and sheep, and NOX emissions from their manure accounted for more than half the total.
The present rise in livestock production and meat consumption therefore threatens global efforts to curb greenhouse gases.
Friday’s report argued that the United States and China could lead a shift to lower carbon diets, in the United States by reinforcing a health-induced shift already underway, and in China by encouraging consumption of pork at the expense of beef.
“We suggest focusing on countries with the highest potential mitigation impact, these being primarily China and secondarily the US,” say the authors.
The United States has already started to curb meat consumption, reflecting growing public awareness of the health risks.
“For the first time on record, U.S. per-capita meat consumption declined by 9 percent between 2007 and 2012. Additionally, the US has shifted its red meat consumption to poultry, seeing roughly a 27 percent decline in beef consumption per capita and a 50 percent increase in poultry since 1970.”
“Many consumers cite health concerns as the primary reason for reducing meat consumption.”
In China, the report noted a preference presently for pork, and considered that reinforcing that preference could avoid a shift to beef.
“Interventions in China could be particularly effective, as the strategy would be to mitigate the projected growth of beef demand rather than changing existing consumer behaviour, a relatively easier task. China’s diets and strong cultural preference for other meats allows the avoided shift to beef without incurring losses in welfare or disrupting culture.”