Farming accounts for 35pc of it
Beef industry alone responsible for some 25 percent of all food emissions
Rice is the worst plant offender, accounting for 12 percent
Animal farming accounts for twice as many greenhouse gas emissions as plants grown for consumption, according to a study published Monday that mapped agricultural activities worldwide.
What humans eat accounts for a major chunk of the emissions behind climate-change -- transportation, deforestation, cold-storage and the digestive systems of cattle all send polluting gases into the atmosphere.
Researchers looked at carbon dioxide, methane and nitrous oxide released by food production and consumption from farming on land. And they found that, from 2007 to 2013, the emissions amounted to 17.318 billion metric tonnes of CO2 equivalent greenhouse gases per year -- or 35 percent of all human-caused emissions.
The study, which modelled net emissions for over 170 plant and 16 animal products in nearly 200 countries, calculated that 57 percent of food-related emissions were from animal-based foods -- including crops grown to feed livestock.
Plants grown for human consumption generated 29 percent of food emissions, the study published in Nature Food found, and the rest was attributed to other commodities like cotton and rubber. It did not include emissions from fisheries.
For better understanding, the research team broke down the globe's farmland into some 60,000 grid squares. This allowed the researchers to model location-specific emissions data for dozens of major crops and animal products.
Beef was the largest-contributing commodity, responsible for some 25 percent of food emissions, and rice was the worst plant offender, accounting for 12 percent.
This helped place cattle-farming South America and rice-growing Southeast Asia as the biggest emitters of greenhouse gasses related to food production.
The study noted the growing demand for food worldwide and the industry's potential to exacerbate global warming.