The food system emits one third of anthropogenic greenhouse gas (GHG) emissions and is projected to contribute 0.9 °C to end-of-century warming. It is also a primary source of methane; a powerful short-lived climate forcer (SLCF) and the second-most important GHG. Most food syste
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The food system emits one third of anthropogenic greenhouse gas (GHG) emissions and is projected to contribute 0.9 °C to end-of-century warming. It is also a primary source of methane; a powerful short-lived climate forcer (SLCF) and the second-most important GHG. Most food system methane emissions result from livestock production and is biogenic (part of the short carbon cycle). As such, livestock emission reductions can actively lower surface temperatures. Despite this, the livestock sector’s current commitments do not meet the IPCC’s 2035 global emissions reduction target. Here, we use the reduced-complexity climate model MAGICC to show that reduction trajectories identified by expert-elicitation for a livestock sector compliant with the Paris Agreement would avoid up to 0.42 °C warming by 2100. Specifically, a reduction in methane emission contributes 76.6% to this cooling in 2050 (of a total of 0.17 °C). Climate studies typically report emissions using GWP100, which underestimates the warming potential of SLCFs in the short term. We assess various climate metrics’ performance relative to MAGICC outcomes, and find better performance for target-aligned time horizons (for both 1.5 °C and 2.0 °C). Our findings reinforce the scientific consensus that reductions in livestock emissions are unavoidable in meeting targets and developing climate policy.