CO₂ emissions: who really has to pay the global bill?

This is an idea that's unsettling because it speaks the only language everyone understands: money. A study published on March 25 in Nature attempts to quantify the economic damage linked to greenhouse gas emissions and, more importantly, to attribute it to identified emitters—states, companies, or individuals. This exercise isn't a laboratory exercise: it relies on observable impacts—heat waves, droughts, storms, effects on health and agriculture—and then links emission volumes to measured economic losses. The ambition is clear: to move beyond the grand global accounting where everyone is responsible, and therefore no one truly is.

The authors acknowledge the political nature of a quantification that is primarily methodological. “The international community has always refused to formally define the concept of loss and damage or to attempt to systematically estimate which emissions cause damage in which countries. Our goal was to fill this gap,” explains Marshall Burke, a Stanford professor and lead author. Behind this term lies an explosive issue: “loss and damage” refers to damage deemed irreversible when neither emissions reductions nor adaptation are sufficient, a topic that has strained climate negotiations for years, with each side fearing the financial consequences and the precedent set.

"Losses and damages" that extend beyond the conference rooms

The study, in fact, puts the figures far ahead, in the trillions of dollars over the last three decades. According to these estimates, US emissions have already resulted in $10.2 trillion in economic losses, China's $8.7 trillion, and the European Union's $6.4 trillion. And the researchers warn that this figure doesn't tell the whole story: carbon dioxide remains in the atmosphere for hundreds of years, its effects continuing after emission, like a loan that was thought to be paid off but whose interest accrues every year.

The major practical question remains: what do we do with these funds? In France, the benchmark carbon price serves as a compass for assessing investments and quantifying the cost of inaction, without directly billing any particular actor. At the European level, the approach relies primarily on standards and the EU-ETS carbon market, while climate disputes and work on the responsibility of major fossil fuel producers maintain pressure. This study adds another piece to the puzzle, more accounting than moral, and could influence how states and businesses will accept being held accountable in the literal sense in the future.