https://thebreakthrough.org/issues/food-agriculture-environm...
In 2013, the Food and Agriculture Organization of the United Nations estimated that livestock production accounted for 14.5% of global greenhouse gas emissions. Though the analysis was based on data from 2004 and 2005—over 15 years ago—it remains the most widely cited estimate of livestock’s global carbon footprint ...
More recent data and science indicate that livestock may contribute a wider range of emissions, potentially more, potentially less. For its part, the Food and Agriculture Organization of the United Nations has released a new, lower estimate that livestock produce 11.1% of global greenhouse gas emissions. Peer-reviewed studies have put the figure higher, at up to 19.6% of emissions.
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Ultimately, it’s unlikely that researchers will agree on a single estimate of livestock’s global contributions to climate change. That figure is a moving target, shifting depending on the year, the method of estimating the warming impact of methane, and many other factors. But one thing is clear: we won’t be able to avoid the worst impacts of global warming without tackling emissions from livestock.