Chapter 01 · Climate & transitionClimate & Greenhouse Gas Emissions
Agricultural emissions
Definition
Greenhouse gases released from agricultural activity, principally methane from livestock digestion (enteric fermentation), rice cultivation and manure management, and nitrous oxide from fertilised soils. Unlike most sectors, agriculture's emissions are overwhelmingly non-CO₂ gases, which are far more potent per tonne than carbon dioxide.
References
US sector shares (~10% of GHGs; ~45% of non-CO₂); sources (enteric fermentation, manure, fertilised soils, rice); trends since 1990.
Global livestock shares (44% of methane, 53% of nitrous oxide); GWP figures (27× and 273× CO₂ over 100 years); emissions-intensity variation.
AFOLU context — agriculture within the ~22% land-sector share of global emissions.
Overview
What it means
In the United States, agriculture accounted for about 10% of total GHG emissions in 2024 but nearly half of all non-CO₂ emissions — 92% of the sector's emissions were methane or nitrous oxide. Globally, livestock are responsible for about 44% of methane and 53% of nitrous oxide emissions. Agricultural emissions form part of the wider AFOLU sector but exclude land-use change and forestry.
How it is used
Countries report agricultural emissions in national GHG inventories using IPCC methods (enteric fermentation, manure management, rice, agricultural soils, field burning). Mitigation options include feed additives, manure management, fertiliser efficiency and dietary shifts. The sector's dispersed, biologically driven sources make measurement and regulation harder than for energy or industry.
Why it matters
Methane and nitrous oxide have 100-year warming potencies roughly 27 and 273 times that of CO₂ respectively, so agricultural emissions punch above their tonnage. Feeding a growing population while cutting these emissions — without offshoring impacts — is one of the hardest problems in climate policy.
Definitions and controversy
Boundary matters: figures quoted as "agriculture" may or may not include land-use change (AFOLU), fisheries, or food-system energy use, producing very different totals.