xtreme inequality is a major challenge of our time. While global wealth is concentrated among a few individuals 1 , hundreds of millions still live in extreme poverty, defined by having less than US$1.90 to spend per day 2 . While international extreme poverty headcounts have been declining steadily, the impacts of the global COVID-19 pandemic might reverse this trend by putting millions of people into poverty 3 . To tackle this problem, the first of the United Nations (UN) Sustainable Development Goals (SDGs), established in 2015, is to 'end poverty in all its forms everywhere' . 4 Its targets focus on eliminating extreme poverty, as well as halving poverty, defined by national poverty lines, by 2030. Furthermore, the World Bank introduced two additional poverty lines for the global scale, one at US$3.20 per day and one at US$5.50 per day (ref. 5 ), to address poverty in countries with higher income levels.In the same year as the SDGs were established, the global community adopted the Paris Climate Agreement and proposed to keep global temperature increase below 2.0 °C or 1.5 °C. This leaves humanity with a limited carbon budget to emit and, thus, requires sizeable reductions of yearly carbon emissions. Currently, not everybody is contributing equally to these emissions. Due to the unequal distribution of wealth and income, there is an unequal distribution of consumption and, in turn, carbon footprints, which cover the carbon emissions caused by the consumption of an individual over the period of one year 6 . These emissions, too, reveal a picture of extreme 'carbon inequality' [7][8][9][10] . Despite a decrease of carbon inequality in recent decades 11,12 , enormous differences between the global rich and the global poor remain. Moreover, growth of absolute CO 2 emissions over the past 25 years was caused mainly by increasing carbon footprints of the top 10% (ref. 9 ). Hence, carbon inequality is a mirror to extreme income and wealth inequality experienced at a national and global level today.This leads to the question of whether both global challenges can be addressed at the same time. Can we lift millions of people out of poverty while controlling carbon emissions? Answering this question requires looking behind the scenes and quantifying the
