Fair National Carbon Accountability for past and future emissions

Abstract

Quantifying fair national shares of the remaining global carbon budget has proven challenging for the Paris Agreement. Here, we propose a new indicator – Fair National Carbon Accountability – that quantifies countries’ responsibility for mitigation and CO2 removal in addition to achieving their own targets. Considering carbon debts since 1990 and future claims due to countries’ emission pathways, the indicator uses an equal cumulative emissions per capita approach to allocate accountability in proportion to countries’ total excessive carbon claims. The carbon budget is exceeded by 565 Gt fossil CO2 when limiting warming below 1.5oC (50% probability). The accountability for these excessive claims is highest for China and the USA, and highest per capita for the United Arab Emirates, Russia, Saudi Arabia, and the United States. The ability to pay for this accountability, however, is challenging for Iran, Kazakhstan and several BRICS members, in contrast to the G7 members.