
they combine disparately methodized LCA data. this is explicitly against good practice. the fact that they found outrageous disparities got them great headlines and impressive graphs, but the underlying science is questionable at best. I could go deeper but this is the thousand foot view.



of course it’s not. Meta analyzes fly in the face of the guidance for LCAs. it’s just not good science.
since I’m already being tasked to address this again, it’s worth pointing out that poore and nemecek didn’t even gather the LCA data themselves. they, themselves, actually cite other meta-analyzes of LCA data. those meta-analyzes do recognize that they are violating best practices in the text themselves, and just go ahead and do it anyway. egregiously, poore and nemecek Don’t even acknowledge this faux pas and pass off their “findings” as sound investigation.