Paper: Livestock, Methane and Climate
Livestock, Methane and Climate
D. Alexander [1], J. D. Ferguson [2], A. Glatzle [3], W. Happer [4], and W. A. van Wijngaarden [5]
January 27, 2026The CO₂ Coalition has released a compelling new paper, "Livestock, Methane and Climate" (January 27, 2026), co-authored by D. Alexander, with four CO₂ Coalition members: J.D. Ferguson, A. Glatzle, W. Happer, and W.A. van Wijngaarden. This rigorous analysis demonstrates that methane emissions from ruminant livestock—such as cattle and sheep—have an effectively undetectable influence on Earth's temperature.
The authors use precise calculations grounded in atmospheric physics, emission data, and radiative forcing models. Their findings are striking: Eliminating all ~1.6 billion cattle worldwide in 2025 would reduce atmospheric methane enough to lower global temperatures by just ΔT = −0.04°C.
For the world's ~1.3 billion sheep, the effect is even smaller: ΔT = −0.004°C. These represent maximum possible savings, assuming no replacement emissions from wild ruminants or termites in rewilded grasslands.
The paper pays special attention to New Zealand's ambitious pledge to cut livestock methane emissions by 14–24% below 2017 levels by 2050. The calculated temperature impact? A minuscule ΔT = −0.000005 to −0.000008°C—far too small to measure with any instrument. Even using IPCC-aligned parameters for cooling capacity yields only marginally larger (yet still negligible) figures.
Why the Minimal Effect?
Ruminants produce methane through essential rumen fermentation, where microbes break down cellulose into nutritious volatile fatty acids, enabling animals to thrive on forage. While methane is a potent greenhouse gas on a per-molecule basis (30 times CO₂), its atmospheric concentration from livestock remains a tiny fraction of the total inventory. Cattle contribute about 17% and sheep ~2% of current methane levels, with short atmospheric lifetimes (9–12 years) limiting long-term buildup.
The authors emphasize that policies targeting these emissions deliver "all pain, no gain."
Drastic measures—like culling herds or imposing heavy regulations—would harm food production, rural economies, and nutrition with no meaningful climate benefit. Natural systems often exhibit negative feedbacks, consistent with Le Chatelier’s Principle, further dampening any effects.
This publication joins other CO₂ Coalition work highlighting that methane concerns (from livestock or pipelines) are overstated relative to their real-world influence. It underscores the need for evidence-based policy over alarmist narratives. Farmers, policymakers, and citizens deserve facts, not fear-driven mandates that threaten agriculture while delivering imperceptible temperature changes.
Paper Abstract
Methane emissions by livestock have a negligible effect on Earth’s temperature. For example, killing all of the approximately 1.6 billion cattle on Earth in the year 2025, when this paper was written, would only reduce atmospheric methane concentrations enough to change the temperature by ∆T = −0.04 C. Killing all 1.3 billion sheep would lead to a temperature change of ∆T = −0.004 C. New Zealand’s pledge to reduce methane emissions of their livestock by 14% to 24% from those in the year 2017 would change the temperature by ∆T = −0.000005 to − 0.000008 C, far too small to measure. These are maximum temperature savings where methane emissions from domestic livestock are not replaced by other sources (such as wild ruminants and termites) during the inevitable rewilding of managed grasslands and rangelands.