Global greenhouse gas emissions from agriculture and food production have risen by 17 percent over the past 30 years, according to UN data, underscoring their importance in limiting climate change. The food system — particularly deforestation from land conversion to agriculture, and methane from the livestock sector — has come under the spotlight for its contribution to global warming.
The sectors accounted for 31 percent of greenhouse gas emissions in 2019, or 16.5bn tonnes of carbon dioxide equivalent, according to a detailed analysis by the UN Food and Agriculture Organization released at the COP26 climate summit in Glasgow.
This compares with the earlier calculation by a UN scientific body, the Intergovernmental Panel on Climate Change, that the agricultural and food systems accounted for 25 to 30 percent of emissions from 2007 to 2016.
Deforestation was the largest source of greenhouse gas emissions in 2019, at about 6 per cent total carbon dioxide equivalent emissions, or 3.1 gigatonnes, according to the FAO. Enteric fermentation, largely from cow burps, accounted for 5 per cent, while livestock manure accounted for 2 per cent.
Methane and nitrous dioxide, gases that are more potent than carbon dioxide because of their shorter-term warming properties, contributed to about 30 per cent of total emissions for the agriculture and food sectors.