Genuine question, not being snarky — how do you even calculate embedded carbon for finished goods with global, multi-country supply chains? Feels close to impossible to audit properly.
On theguardian.com — see it on the live page
Not impossible but it's ugly — default emissions-intensity benchmarks per product/country pairing, with self-reporting for anyone who wants to prove they beat the default. It's basically how CBAM does it today. Gameable at the margins but auditable in aggregate.