One-third of the global greenhouse gas emissions caused by humans are linked to the process of food production, say a new study published in the journal Nature Food.
The report found that food-system emissions which include the process of production, packaging and transportation represented 34 percent of total greenhouse gas output in 2015.
About half of these emissions were carbon dioxide released from land use, deforestation and the process of packaging, transportation and processing of food items. Methane which is 28 times more potent than CO2 constituted a third of emissions and the remainder was largely nitrous oxide from fertilizers.
The researchers said that the global food system is becoming more energy-intensive with transportation accounting for 4.8 per cent of total 2015 food system emissions and packaging, 5.4 per cent.
Refrigeration and its association with fluorinated gases were also estimated to be responsible for 43 per cent of energy consumption by the retail and supermarket sector.
Asia was found to be the highest contributor producing 35 per cent of global food system emissions in 1990 and 49 per cent in 2015.
The six top food system emitters in 2015 were China (13.5 percent of the global total), Indonesia (8.8 percent), the United States (8.2 percent), Brazil (7.4 percent), the European Union (6.7 percent) and India (6.3 percent).
The research is based on a new global database that provides estimates of food system greenhouse gas emissions from 1990 to 2015 and according to the European Commission's Joint Research Centre, it is the first to encapsulate all countries and sectors from production, packaging and distribution to disposal of food waste.
The study called for policies to improve efficiency , reduce emissions in the supply chain, and enable people to access healthier diets. The authors believe the issue will be discussed in detail and a way to mitigate will be suggested by the UN Food Systems Summit to happen later this year.