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Comment by dbingham | Hacker News Reader

Source please.

There's currently a propaganda war between multiple powerful lobbies - the animal rights lobby, the meat producers, conventional ag producers, and more - which means there is a ton of misinformation flying around about the actual environmental impacts of eating meat. Really, of all things dietary.

Meanwhile there are a bunch of people exploring alternate agriculture systems through agroecological approaches that show a lot of promise, but haven't been studied enough to really make claims about either way.

Further, you cannot just say "x amount of finished beef produces y emissions" because there are so many factors that go into it. Feedlot vs traditional range vs intensive rotational vs silvopasture are all different with completely different environmental impacts - of which carbon is only one.

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https://ourworldindata.org/explorers/food-footprints

Again, that is a chart based on a single source. Which may or may not be open access and I've been through enough of these tonight, but look at my other comments on similar sources to see my problems with them. All too often they are based on "accepted dataset" which are full of all kinds of faulty assumptions and modeling. Meanwhile, there are people going out and actually measuring agroecology systems and finding a totally different result.

https://www.sciencedirect.com/science/article/pii/S0308521X1...

That source is primarily examining conventional feedlot approaches.

> An all grass cow-calf – to – finish operation was included as a minor component in the eastern and northwestern regions

They examined a single all grass finished operation. There are studies that have found grass finishing can cut emissions in cattle by as much as 80%.

> The modeled operations were not intended to be actual operations; they were developed to represent the practices found in each region.

> Environmental footprints for all individually simulated ranch and feedlot operations were integrated into full production systems within their respective study regions using two methods

They also don't appear to be measuring actual operations, but rather modeling operations based on surveys of farmers and ranchers about the characteristics of their operations and then extrapolating from there.

Models have their place for sure, but I wouldn't make any kind of declaration of certainty based on a single model-based study. You have to average the outputs of hundreds or thousands of models, and even then, you can't be sure you have the answer.

A better approach would be one that measures the actual output of each operation at various phases and averages across them. Difficult to do, but I've seen studies that attempted it.

I guess I expected that if you wanted to see sources you would retort with your own published sources.

Gladly, although, with the caveat that science works in the aggregate so any individual paper should be treated with skepticism and that I have no idea what quality of journals these are coming from because the open access literature is currently a royal fucking mess.

But here's a paper that found that properly grazed beef could not only potentially reach net-zero emissions, but might even be a carbon sink: http://www.thefutureoffoodjournal.com/index.php/FOFJ/article...

Here's another study that found that the soil type of the grassland and the dominant species of grass had a significant effect on whether intensively grazing it sequestered or released carbon from the soil overall:

https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.12144

And that one appears to be a literature review of other studies.

Related note, you have to be so careful looking through the studies, here's one that purports to compare the different systems. But when you read the abstract it uses "A deterministic model based on the metabolism and nutrient requirements of the beef population". In other words, they aren't actually measuring anything. They just have numbers in a database for "x lb of beef requires y inputs" and "x lb of beef gives z outputs" and they're crunching those numbers under assumptions about the productivity of each approach. Naturally, they find that conventional feedlots are the most environmentally friendly.

https://www.mdpi.com/2076-2615/2/2/127

Note that one's also in an MDPI journal, which MDPI has begun to get a reputation as a pay to play paper mill.

Thanks! Not my subject area at all, so I'm happy to read these.

I mean, the paper uses data from the National Cattlemen's Beef Association™, which is a beef lobbying group. The third author of the paper is also from the NBCA, and the paper was funded by the Beef Checkoff™, which a beef marketing program. I have my reservations about the accuracy of this paper.

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