Emission factors express the warming potential of greenhouse gases (GHGs) relative to carbon dioxide (CO₂) , usually known as Global Warming Potentials (GWPs) over a 100‑year period (GWP₁₀₀). The most recently adopted authoritative values come from the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6, 2021) — which many international and regional regulators (including the  EU ETS,  UK DEFRA, and  ISO 14064‑1:2018 updates) have begun using or r