Rapid global phaseout of animal agriculture has the potential to stabilize greenhouse gas levels for 30 years and offset 68 percent of CO₂emissions this century

Abstract

We used public data on greenhouse-gas emissions and land use to evaluate the potential impact of eliminating animal agriculture on atmospheric greenhouse gas levels, and global warming potential. We first updated estimates of carbon dioxide, methane, and nitrous oxide emissions from livestock and livestock feed production. We used these data, along with recent estimates of the atmospheric carbon dioxide that could be converted by photosynthesis into perennial biomass on land currently engaged in animal agriculture, to develop models of net anthropogenic emissions under food-system scenarios ranging from business as usual to the complete elimination of animal agriculture. We then used simple simulations to project atmospheric levels of these three gases through the end of the century under each scenario. Using cumulative differences in radiative forcing as a measure of the impact of different diets, we found that a gradual transition over the next 15 years to a plant-only diet would have the same effect through the rest of the century as an annual reduction of 28 Gt of CO2 emissions. This would effectively negate 56 percent of global emissions at the current rate of 50 Gt CO2eq per year, with a net negation of 2,200 gigatonnes of CO2 emissions by the year 2100. The climate benefits would accrue rapidly - most in the first few decades, effectively pausing greenhouse-gas accumulation for 30 years. These results establish the replacement of animal agriculture as by far the most powerful option in our arsenal of climate-defense strategies, especially given the urgency of the climate threat. How to orchestrate such a shift to maximize its beneficial environmental, public health, food security, economic and social consequences and minimize potential harms should therefore be at the center of climate policy discussions.

Climate change and broiler production

“…A recent study exploring the environmental impacts of food products (Figure 2 ) uncovered that poultry meat contributed 9.87 kg CO₂eq per kilogramme, which was lower than that obtainable from cattle (beef and dairy herd), lamb and mutton and pig meat production (Poore & Nemecek, 2018 ). According to estimates, chickens will produce 0.6 Gt of CO 2 ‐equivalent emissions or contribute to 8% of total emissions from the animal industry (Eisen & Brown, 2021 ). Specifically, for broiler production, 78% of feed production, 8% of direct energy consumption on farms, 7% of post‐farm meat processing and shipping and 6% of manure storage and processing are responsible for GHG emissions (MacLeod et al., 2019 ).…”

(Not So) Happy Cows: An Autonomy‐Based Argument for Regulating Animal Industry Misleading Commercial Speech

“…25 Indeed, it is estimated that the end of animal agriculture 'would have the same effect, through the end of the century, as a 68% reduction of CO 2 emissions'. 26 Happy cow messages hide the connection between the animal-based products we find in the market and the environmental problems to which their production contributes.…”

Looking to “junk” food to design healthier options

“…At Impossible Foods, the mission is to protect the environment through dietary change. CEO Patrick Brown recently coauthored a preprint finding that eliminating animal agriculture over the next 15 years would cut 56% of global greenhouse gas emissions by 2100 (1). Not only does the company strive to replicate what consumers love about beef, but "if things are not great, like the environmental footprint, and high cholesterol, we don't put those in," Holz-Schietinger says.…”