Scientists found in their study that the global food system was responsible for 16 billion metric tons of greenhouse gas emissions in 2018, or a third of all global emissions that year. This is a sharp contrast to the more narrowly defined agriculture sector of the IPCC’s categories for greenhouse gas inventories, which accounted for 5.3 billion metric tons in 2018, or just a tenth of the total.
“The national greenhouse gas inventories, [under] the IPCC guidelines, are breaking up the components of the food emissions, separating them, and burying them in [other] categories.”
The new analysis accounts for those emissions that the IPCC allocates to non-agricultural categories, including carbon dioxide from pre-production, like manufacturing fertilizer and farm equipment, and post-production emissions, such as food waste disposal, refrigeration, packaging, and transportation. It also includes as food-related emissions the conversion of natural ecosystems to agricultural land, which at nearly 3 billion metrics tons per year are the largest single source of greenhouse gas emissions in their analysis.
Source: CivilEats