On emissions, double counting is not the problem

We’ve just wrapped up the third-hottest year in recorded history, according to results released Jan. 14 by the Copernicus Climate Change Service. The planet is now more than 1.5 °C warmer on a running 3-year average than it was before humanity started powering and synthesizing our society with fossil fuels, a threshold that climate scientists have warned us not to cross (Science 2022, DOI: 10.1126/science.abn7950).Far from supporting an all-hands effort to back away from climate catastrophe, though, some industrial leaders are rehashing old arguments about how to count everyone’s carbon dioxide. We should be skeptical when for-profit multinational corporations in hard-to-abate industries say we must change the methods used to hold them accountable for their greenhouse gas emissions. But the incumbent counting system is flawed. For several years now, the global consensus has been to break emissions into three “scopes.” Scope 1 includes emissions under the operational control of the company in question. For chemical makers, examples are process emissions, the CO2 emitted as a by-product of reactions such as ethanol fermentation, the fuel consumed by company vehicle fleets, and any emissions from R&D labs. Scope 2 is the emissions associated with any energy the company buys.It’s at Scope 3 that the disagreements begin. This outmost layer of emissions includes both upstream activities such as the production of raw materials by vendors and downstream emissions that happen during the sale, use, and final fate of a product. That complex combination of activities gets hard to count. The current system, Scope