Countries that emit more than their fair share of global emissions owe around $192trn in compensation to low-emitting countries, finds a new study published in Nature Sustainability on 5 June. On average, climate reparations would amount to more than $6trn a year for the next three decades, with the US having the largest climate debt at $2.6trn a year, or $7,236 annually per capita.

The authors calculated the compensation owed based on each nation’s share of global emissions and of the global carbon budget. The carbon budget is the amount of greenhouse gases the world can still emit and limit global temperature rise to 1.5°C above pre-industrial levels. In addition to being disproportionally responsible for climate change, the world’s highest emitters are overshooting their fair share of the remaining carbon budget.

The remaining carbon budget is being rapidly depleted. An Energy Monitor investigation published in January 2023 revealed that the expansion plans of Big Oil alone would eat up the entire remaining carbon budget.

The Nature Sustainability study authors argue that since the atmosphere is shared, everyone should have equal use. From that perspective, the carbon budget should be shared equally as well. When one country emits more than its fair share, it appropriates the carbon budget of another country and should pay compensation, or climate reparations, they argue.

Projections from the analysis show that under business-as-usual, the world will blow the remaining carbon budget by 2030. With ambitious mitigation global warming could be limited to 1.5°C, but it would mean high-emitting countries eat into the carbon budget of low-emitting countries.

Even if countries in the Global North achieve net zero by 2050, they will still use three times their share of the 1.5°C carbon budget, appropriating half of the carbon share of the Global South, the study finds. According to the analysis, the 129 countries in the Global South are home to more than 80% of the world’s population. The Global North comprises just 39 countries.