I'm on mobile rn. can you link the bibliography

I didn't lie at all: the other user doesn't seem to know how poore and nemeceks lcas are calculated in the first place

you know as well as I do that the meta analysis is depending on studies that do exactly what I said, and relying on papers that employ a flawed methodology is, itself, a flawed methodology.

I have and you are splitting hairs about this

this is splitting hairs.

the conclusion is "beef produces 85kg co2e". it's calculating exactly what I said.

they take a myopic view of the inputs and outputs for food sources, not considering, for instance, that much of what is fed to animals would otherwise be wasted. the beef doesn't produce all that CO2, poore & nemecek were calculating all the co2 that goes into the inputs. i mentioned elsewhere cottonseed, but frankly i know that only takes up a minute portion of what they're calculating. instead, they are also counting soy, and that's almost as dishonest as you can get. nearly all soy is pressed for oil, and after that, the waste product is what is fed to cattle and other livestock. technically, you could eat it, but most people don't and don't want to. feeding it to livestock actually reclaims waste products. and even the calculation for the soy itself is skewed since it often also counts the deforestation that has already taken place as an emission source, regardless of whether that particular plot of land has been deforested for decades.

as just one facet, they count everything fed to beef, including cottonseed, when calculating the inputs. but cotton isn't grown for cottonseed. if we didn't feed a large portion of our annual cottonseed to livestock, it would just be wasted. vegans will tell you that the return is only 1/10 of the input, but that's a lot better than 0/10.

the paper tries to quantify all the inputs and outputs for foods, but it fails to actually calculate either the actualy outputs (like non-food animal products), or the actual costs of the inputs (many of which would be waste products)

if you total all the inputs that go into a product (the water, the carbon emissions, the land use, etc), then you can see what it would cost to produce it if you made no other products. but that's not actually the environment in which meat dairy and eggs are produced.

the most illustrative example is cotton. cotton is not a food. it is grown for textiles. it wrecks the soil and it is THIRSTY. after you harvest the cotton and separate the fiber from the stalk and seed, you have seed left over. way more seed than you need to replant. cottonseed can be and is pressed for oil, but it takes much less processing to mix it into cattle fodder. why should the water used to grow cotton count against the water inputs for beef and milk? it's actually a conservation of resources. these industries are all interconnected, and trying to just put a singular value on every product in the absence of the context of its production is not actually useful in determining what would be ecologically responsible.

poore nemecek's methodology is flawed.

poore nemecek had flawed methodology and should not be the basis of policy decisions.

this is based on the poore-nemecek study and should not be regarded as "true". it's "true if they methodology reflects reality" but it does not.