Voluntary climate pledges widen what firms measure, not what they abate
This study finds that voluntary science-based climate pledges primarily lead firms to expand the scope of their emissions reporting—specifically by including more Scope 3 categories—rather than driving actual reductions in emissions, suggesting that observed increases in reported figures reflect accounting changes rather than genuine abatement.
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To understand the climate challenge facing the modern world, one must first grasp how companies are asked to measure their impact. For decades, the primary tool for tracking corporate pollution has been a system of voluntary promises. Thousands of large businesses have signed up to reduce their greenhouse gas emissions, often committing to targets that align with the global goal of limiting warming. These promises are judged by the numbers companies report to themselves and to the public. The logic seems straightforward: if a company promises to cut pollution, its reported emissions should go down over time. If the numbers drop, the promise is being kept; if they stay the same or rise, the company is failing. This system relies on the assumption that the way a company counts its pollution remains constant, so that any change in the total reflects a real change in the physical amount of carbon released into the atmosphere.
However, a new study challenges this fundamental assumption. It suggests that the act of making a promise changes not just the pollution, but the very ruler used to measure it. When a company commits to a science-based target, it is required to look much deeper into its supply chain, counting emissions from purchased goods, transportation, and the use of sold products—categories that were often ignored or only partially counted before. The research finds that this shift in measurement creates a confusing picture: companies appear to be emitting more simply because they are finally counting more of what they were already emitting. The study concludes that the visible rise in reported numbers is often a sign of better bookkeeping, not a failure to act, and that the actual reduction of pollution remains hidden behind the expanding scope of the count.
Florian Pothin, a researcher at the University of Rennes, set out to test whether these voluntary pledges actually lead to less pollution or simply lead to more complete reporting. He analyzed data from thousands of companies over an eight-year period, comparing those that made a pledge to those that had not yet made one. The study focused on three types of emissions: direct pollution from a company's own operations, indirect pollution from the energy they buy, and the vast, complex web of pollution created by their supply chains and products. By using a rigorous statistical method that accounts for the timing of when different companies made their promises, Pothin could isolate the specific effect of the pledge itself.
The results revealed a clear and immediate change in behavior. Within four years of making a pledge, a company began reporting on roughly two and a half more categories of supply-chain emissions than it had before. This was not a gradual improvement; the shift happened quickly after the commitment was made. As a result, the total amount of emissions reported by these companies jumped significantly in the first two years. The data showed that reported emissions from the supply chain increased by a large margin, but this increase was entirely driven by the fact that the companies were now counting categories they had previously left out. It was as if a person who had only been weighing their groceries on a small scale suddenly started weighing their entire pantry; the total weight would go up, not because they bought more food, but because they finally measured everything they already owned.
When the researcher looked at the direct emissions from a company's own operations, the story was different. These numbers, which are the hardest to manipulate and do not rely on certificates or estimates, showed no significant change. They remained flat, suggesting that the companies were not reducing their direct pollution at a pace that could be detected by the study. The slight drop seen in the total emissions of some companies was traced entirely to the purchase of renewable energy certificates, which allow a company to claim a reduction on paper without necessarily changing the physical fuel they burn. In the most critical area, the supply chain where the majority of a company's footprint lies, the reported numbers rose sharply. But when the researcher adjusted the data to keep the measurement boundary fixed—forcing the companies to count only the same categories they counted before the pledge—the rise disappeared. In fact, within that fixed boundary, the numbers showed a slight decline, suggesting that some real reduction might be happening, but it was completely masked by the expansion of what was being counted.
The study argues that this phenomenon creates a major problem for anyone trying to judge corporate climate action. Because the companies themselves decide which categories to include in their reports, the act of promising to reduce emissions changes the yardstick used to measure success. A company can appear to be making no progress, or even getting worse, simply because it has started to count more of its pollution. Conversely, a company could be making genuine cuts, but those cuts would be invisible if they were offset by the inclusion of new categories. The research shows that the increase in transparency is real, but it is not a reliable indicator of whether pollution is actually decreasing. The numbers on the page reflect a change in accounting rules, not necessarily a change in the physical world.
This finding suggests that the current system of voluntary pledges is flawed not because companies are lying, but because the system rewards a broader inventory of data rather than a reduction in the data itself. The study concludes that to truly know if a company is cutting its emissions, observers cannot rely on the total numbers the company reports, as those totals are constantly shifting. Instead, evaluations need to use a fixed standard that does not change when the company makes a promise, or rely on independent verification that does not depend on the company's own choices about what to count. Until such measures are in place, the rising or flat numbers seen in corporate reports should be understood as a sign of better measurement, not a failure to act, and the true progress of the private sector in fighting climate change remains largely hidden from view.
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