Anthropogenic climate change is caused by multiple climate pollutants, with CO₂, CH₄, and N₂O the three largest individual contributors to global warming (Myhre et al., 2013). Agriculture and food production is associated with all three of these gases, but direct agricultural emissions are unusual in being dominated by CH₄ and N₂O.

Food system CO₂ emissions are somewhat harder to quantify, due to the distinct processes through which they are generated and difficulty in applying uniform accounting methods or sectoral boundaries. The focus on reducing (to net zero) our CO₂ emissions is well justified not just because it is the major anthropogenic climate forcer but also because it acts cumulatively.