Eradicating extreme poverty and stopping climate change are two urgent global challenges, and they can only be tackled together. Eradicating extreme poverty in a sustainable manner requires limiting the future socioeconomic and environmental impacts of climate change; and there is broad consensus that, to be feasible and sustained, the emissions reductions needed to stop climate change have to be achieved through a just transition, which in particular protects the poorest and most vulnerable.<sup>1,2</sup> The Sustainable Development Goals (SDGs), aspiring to a ‘better and more sustainable future for all’, attest to the combined importance of these issues. The first of the SDGs calls to ‘end poverty in all its forms everywhere’. Eradicating poverty is also atop the agenda of the World Bank, which aims to decrease the share of people living in extreme poverty – with less than $2.15 a day at 2017 PPP – to 3% or less by 2030.<sup>3</sup> SDG 13 focuses on ‘urgent action to combat climate change and its impacts’.<sup>4</sup> To this end, the Paris Agreement was adopted in 2015 by 196 countries with the goal to limit global warming to “ _well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels_ .” This would require reaching global net-zero emissions levels by or close to mid-century, with emission reductions going well beyond the reductions that have been achieved so far.<sup>5,6</sup> Eradicating extreme poverty requires raising the consumption levels of the global poor to at least $2.15 a day. However, rising income and consumption levels have historically been the main drivers of increasing CO2e emissions.<sup>7</sup> This raises the question whether, and under which conditions, containing climate change and eradicating poverty are compatible goals.

Existing research has approached this question by calculating the carbon footprint associated with the consumption of individuals at different income levels using consumption and expenditure surveys.<sup>8–10</sup> These studies simulate shifting up the consumption value of the world’s extreme poor to the poverty line and estimate the emissions associated with this hypothetical consumption shift. Studies using this approach have generally found that eradicating poverty leads to modest increases in global emissions, with estimates ranging from less than 1% to about 3%.

Here we approach this question with a different, more realistic, framing. Poverty reduction occurs by a combination of economic growth and distribution of this growth across households, with 90% of historical poverty alleviation driven by economic growth.<sup>11–14</sup> We estimate the carbon emissions implications of various growth scenarios (for aggregate growth and the distribution of this growth among the population) under which poverty would be eradicated. With this framing, eradicating poverty requires not only to increase the consumption of poor people but also, under realistic assumptions for the distribution of growth based on historical patterns, to increase the consumption of non-poor people. Therefore, eradicating poverty is expected to lead to higher emissions with this framing than in previous studies if the energy and carbon contents of economic growth follow historical patterns.

To achieve the world’s poverty and climate objectives, the future will need to differ markedly from the past. In particular, we analyze how changes in income inequality and in the energy and carbon intensity of economic growth can contribute to reconciling poverty and climate goals. Previous studies have documented stark inequalities in emissions between poorer and richer individuals and households, drawing attention to high emitters in all countries, which contrast with the minimal emissions contributions of the world’s poorest.<sup>15–17</sup> A separate body of research examines whether reducing income inequality increases the emissions intensity of GDP.<sup>10,18–23</sup> Here we show that lower inequality means that less growth is needed to eliminate extreme poverty, which in turn reduces the emissions of poverty alleviation significantly. On the flipside, rising inequality can escalate the carbon cost of poverty alleviation and exacerbate the trade-off between climate goals and eradicating even extreme poverty.

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