This man looks like the evil Karl Jobst.

Big assumption that Hulk Hogan is in Heaven.

they don’t do this, though, they just charge ahead compiling the data.

Actually, they do exactly this, and how they do it is detailed fairly extensively in the study in Section 2: ‘Methodology’. I hope you understand the preview that Elsevier gives you isn’t the full article. I’m accessing this through the Wikipedia library, but this article happens to be available publicly through Lancaster University.

Section 2.1, “Systematic review strategy”, describes how they gathered articles and what criteria they used to include or exclude them. Next, Section 2.2 (about 2.5 pages) goes into detail about “Synthesizing results for comparison”, detailing how the Global Warming Potentials (GWP) of all of the 369 LCAs were converted into a common functional unit (thereby enabling comparison) for analysis. Finally, a brief Section 2.3 shows how the actual meta-analysis was performed.

I hope this helped. :)

I was just genuinely curious because I’ve seen this pattern from you a lot before, and it’s highly unconventional. I latched onto this comment because I think it had the least salient/debatable/falsifiable point, namely “their methodology isn’t good”.

You’ve accused me elsewhere of appealing to scientific authority (which, yes, neither of us are qualified or experienced in this field in any way; we have to weigh what the relevant experts say and do), then you quote an authority to show that this is actually allegedly bad. But then that same authority says actually, no, this is good. And if you’re referring to the papers they cite in that paragraph as your sources of choice (still an appeal to authority), then you now have the challenge of explaining why those numerous authors whose papers are cited haven’t rebutted not now just one (Poore & Nemecek 2018) but two meta-analyses synthesizing hundreds of LCAs.

Is your pattern of posting multiple replies to the same comment some kind of strategy? One reply per user per comment (sometimes two in weird, extenuating circumstances) isn’t enforced, but it’s the norm because doing what you do makes the comment chain extremely chaotic and messy. I can’t imagine you’re trying to use the comment chain structure itself to muddy the waters, are you? Surely this can’t be an ideal experience for you either?

That’s your characterization here? That’s the level of bad faith you’re acting on? That they spent an entire paragraph right upfront citing other papers talking about potential pitfalls for the express purpose of intentionally implicating themselves before doing it? Are you high? Or just deeply scientifically illiterate?

The entire point of that paragraph is to show that there are pitfalls if taking a naïve approach, but that an appropriately thought-out meta-analysis can meaningfully synthesize LCAs into one set of data, which they go on to explain in their ‘Methodology’.

It’s exceptionally funny to me that you didn’t link to the study you’re quoting, because if you did, people would find out that you’re quoting a systematic review & meta-analysis of 369 LCA studies in the same vein as Poore & Nemecek 2018 did with 1530 LCA studies.

The ENTIRE POINT of the study you just quoted was that “there is a lack of synthesised open access LCA data in the public domain available to consumers to inform decision-making. Therefore this paper presents a systematic literature review and meta-analysis of food LCA studies in the last 15 years to assess the GWP of fresh food.” Thus, they appropriately synthesized the data using a meta-analysis. You’ve literally just disproven your own point. I hope you don’t actually believe that people reading this comment will fall for this.

I’m not trying to taunt you, rather I’m being completely serious: did you read the study you just linked beyond what you quoted?

So what I’m hearing here is that despite this being an ISO standard, thereby rendering this trivially obvious even to someone with zero background in this field:

• Poore & Nemecek saw and see no issue with it.
• The peer reviewers for one of the world’s top academic journals see no issue with it.
• None of the 100+ authors of the 40 papers cited see any issue with it.
• Having read this, none of the hundreds upon hundreds of environmental scientists for whom this is their life’s work and who are orders of magnitude more informed on this than you or I see no issue with it.
• The animal agriculture industry – which again, absolutely has the means and the overwhelming financial motive to refute this – sees no issue with it.

I’m sorry for “appealing to authority” when all you have to offer is the same flimsy, nonsensical vagary over and over again. If you’ll recall, I even asked you last time to point to one of the references calling what Poore & Nemecek did here unjustified, and you refused, likely because you’ve never actually read a single one of the 40 referenced papers in your life.

This is the FUD I was referring to. I’ve asked you before to point to even a single paper responding to this extremely high-profile meta-analysis with something even resembling this vague concern; you haven’t been able to turn one up. This should be trivial, because an LCA is an ISO standard, and thus failure to comply with it would be unambiguous for the hundreds if not thousands of scientists familiar with LCAs who have surely read and even cited this paper. I’ve even pointed out that the animal agriculture industry would be champing at the bit to refute a paper like this and has millions of dollars and teams of scientists to throw at the problem. But you can’t, because one doesn’t exist.

Your entire argument boils down to “Um, actually, meta-analyses are bad science”, which is completely hilarious. Hell, assuming Poore & Nemecek, the peer reviewers, and the entire scientific community ignored this alleged basic oversight, I’ve pointed out to you multiple times that you yourself could author a paper rebutting this and get it published if what you’re saying is even remotely credible. But it isn’t. Because you have no idea what you’re talking about regarding this paper except to the extent that you’re lying.

Edit: I’ve asked you this before: please, learn how to edit your comments so you don’t have to respond to this one with three separate comments.

To clarify what this user is referring to, Poore & Nemecek 2018 is a recent, widely cited meta-analysis covering over 1530 studies assessing the environmental impacts of food. It’s published in one of the world’s top academic journals – Science – and authored by Dr. Joseph Poore, the director of the University of Oxford’s food sustainability program, and Dr. Tomas Nemecek, an expert on agroecology and life cycle assessments from the Zurich University of Applied Sciences.

They somehow constantly appear like a spectre whenever this study gets brought up to try to spread FUD about it through vague and unsubstantiated nonsense. They do this because it’s extremely compelling, effectively unambiguous evidence that many animal products such as dairy are abysmal for the climate (“because it’s devastating to my case!”). I highly encourage anyone interested to read it for themselves. The article is paywalled, but Dr. Poore hosts it for free through their personal website, so you don’t have to take either of our words for it.

Edit: the paper they quote (but conspicuously don’t link to) below to try to refute this methodology is itself a meta-analysis of 369 LCA studies in the same vein as Poore & Nemecek. I can’t; my sides are in orbit. Edit 2: For anyone wanting to read it in full, Lancaster University hosts Clune, Crossin & Verghese 2015 legally and for free as well, so again, you don’t have to take either of our words for it.