Not for the first time...

2010:

*****

https://www.monbiot.com/2010/09/07/strong-meat/

'A new book has forced me to reconsider my views on food. [...] [In 2002] After reviewing the figures, I concluded that veganism “is the only ethical response to what is arguably the world’s most urgent social justice issue.” I still believe that the diversion of ever wider tracts of arable land from feeding people to feeding livestock is iniquitous and grotesque. So does the book I’m about to discuss. I no longer believe that the only ethical response is to stop eating meat.

In Meat: a benign extravagance, Simon Fairlie pays handsome tribute to vegans for opening up the debate(2). He then subjects their case to the first treatment I’ve read that is both objective and forensic. His book is an abattoir for misleading claims and dodgy figures, on both sides of the argument.

There’s no doubt that the livestock system has gone horribly wrong. [...] But these idiocies, Fairlie shows, are not arguments against all meat eating, but arguments against the current farming model. [...]

Similarly daft assumptions underlie the UN Food and Agriculture Organisation’s famous claim that livestock are responsible for 18% of the world’s greenhouse gas emissions, a higher proportion than transport(4). Fairlie shows that it made a number of basic mistakes. It attributes all deforestation that culminates in cattle ranching in the Amazon to cattle: in reality it is mostly driven by land speculation and logging. It muddles up one-off emissions from deforestation with ongoing pollution. It makes similar boobs in its nitrous oxide and methane accounts, confusing gross and net production. (Conversely, the organisation greatly underestimates fossil fuel consumption by intensive farming: its report seems to have been informed by a powerful bias against extensive livestock keeping).

Overall, Fairlie estimates that farmed animals produce roughly 10% of the world’s emissions: still too much, but a good deal less than transport(5).

*****

vs. 2022:

*****

https://www.monbiot.com/2022/11/14/silence-of-the-lambs/

Livestock farming is responsible for more greenhouse gas pollution than all the world’s transport. Yet governments won’t touch it.

There are just two actions needed to prevent catastrophic climate breakdown: leave fossil fuels in the ground and stop farming animals. [...]

Livestock farming, a recent paper in the journal Sustainability estimates, accounts for between 16.5% and 28% of all greenhouse gas pollution. The wide range of these figures is an indication of how badly this issue has been neglected. As the same paper shows, the official figure (14.5%), published by the UN Food and Agriculture Organisation, is clearly wrong. Everyone in the field knows it, yet few attempts have been made to update it.

Even if the minimum number (16.5%) applies, this is greater than all the world’s transport emissions. And it is growing fast. [...]

This issue has become even more urgent now we know the heating impact of methane is rising. Livestock farming is the world’s greatest source of methane released by human activities. Yet there is no mention of it in the Global Methane Pledge launched at last year’s climate summit.

*****

Had a brief look at the papers he cites, and could find no indication that the authors had looked at the methane question (though the second paper is behind a paywall), apparently taking its 'global warming potential' as a given:

https://www.mdpi.com/2071-1050/13/11/6276/htm
https://www.nature.com/articles/s43016-021-00358-x

In the absence of anything more persuasive I'm sticking to Fairlie's analysis.

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