Are climate goals compatible with reducing poverty?

In order to avoid more than 1.5°C of global warming, the world has eight years to halve its greenhouse-gas (ghg) emissions relative to 2010 levels. The un’s Sustainable Development Goals require emissions to halve by 2030. They also aim to eradicate extreme poverty—defined as those living on less than $1.90 a day, measured at purchasing-power parity—by the same date. Are these two in conflict? Not as much as you might think.

A study published in Nature Sustainability this week demonstrates how eliminating extreme poverty should not imperil efforts to mitigate climate change. A team led by Benedikt Bruckner of the University of Groningen has, for the first time, compiled a comprehensive estimate of the distribution of carbon consumption across 116 countries, accounting for 87% of the world’s population. The data cover 201 categories of spending on goods and services, such as rice and hairdressing. The researchers calculated the amount of CO₂ associated with each activity or product consumed—including both direct and indirect CO₂ emissions—across households, governments and companies. By linking spending to carbon footprints they were then able to split out the dirtiest and cleanest emitters in every country.

The research highlights enormous inequalities in emissions. It finds that the top 1% of global emitters were responsible for 15% of global emissions in 2014, while the bottom half accounted for just 10% of emissions. The average American had a carbon footprint 11 times larger than that of the average Indian. The top 20% of American emitters had an average footprint 400 times larger than that of the bottom 20% in sub-Saharan Africa.

The researchers then model what effect poverty reduction might have on ghg emissions. Because they consume little, people living in extreme poverty typically have a tiny carbon footprint—emitting about one-tenth of the carbon of the average person on Earth. In 2014, the 350m Indians in extreme poverty were thought to account for just one-tenth of their country's emissions. Lifting them out of extreme poverty would increase India's emissions by just 4%. And lifting the 1.2bn people included in the analysis out of extreme poverty in 2014 is reckoned to lead to an increase of just 1% in global emissions.

Of course, if every person on Earth consumed at the rate of the average American, carbon emissions would increase greatly—about three-fold. The environmental consequences of that scenario would be devastating. But even if 3.6bn people were lifted above a poverty line of $5.50 a day, emissions would increase by just 18%. By contrast, if the world's top 50% of emitters halved their carbon footprints, total emissions would fall by 40%. Although the burden of reducing carbon emissions will fall on all countries, the new research is a timely reminder to some governments that reducing poverty should not excuse their commitment to averting a climate disaster. ■

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