Climate change & the global inequality of carbon emissions, 1990-2020
In this study, Lucas Chancel estimates global greenhouse gas (GHG) emissions inequality between 1990 and 2019, based on a newly assembled global dataset of income and wealth inequality from the World Inequality Database and on Environmental Input-Output tables. The data shows that the richest 10% of the global population emits nearly 48% of global emissions in 2019, the top 1% emits 17% of the total, whereas the poorest half of the global population emits 12% of global emissions. While two thirds of the inequality in individual emissions was due to emissions inequalities between countries in 1990, the situation has entirely reversed in 2019: 63% of the global inequality in individual emissions is now due to gaps between low and high emitters within countries. Lastly, a lot of efforts need to be done by governments to properly monitor carbon inequalities. Absent such information, it is impossible to assess the distributional impacts of climate policies.
📥 The latest version of this research was published in Nature Sustainability and should be referred to in priority as it contains more up-to-date data and an enhanced methodology.
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- At the global level, the top 10% of global emitters (771 million individuals) emit on average 31 tonnes of CO2 per person per year and are responsible for about 48% of global CO2 emissions. The bottom 50% are responsible close to 12% of global carbon emissions in 2019 (3.8 billion individuals who emit on average 1.6 tonnes per person). The global top 1% contribute to 17% of CO2 emissions in a year (they emit on average 110 tonnes).
- Global inequality in per capita emission is due to large inequalities in average emissions between countries and to even larger inequalities in emissions in each country. Currently, average emissions in Europe are close to 10 tonnes CO2 per person and per year. In North America, the average individual emits around 20 tonnes. This value is of 8 tonnes in China, 2.6 tonnes in South & South-East Asia and 1.6 tonnes in Sub-Saharan Africa.
- Historical emissions inequality between regions are very large: North America and Europe are responsible for around half of all emissions since the Industrial Revolution. China represents about 11% of the historical total and Sub-Saharan Africa just 4%.
- Since 1990, emissions from the top 1% have risen faster than any other groups because of the rise in economic inequalities within countries and because of the carbon content of their investments.
- Per-capita emissions levels of the poorest half of the global population only moderately increased since 1990, from 1.2 tonnes to 1.6 tonnes over the period. Average emissions of the global bottom 50% remain today about 4 times below the global average and the poorest billion of individuals on earth billion emit less than one tonne CO2 per capita per annum.
- In many rich countries, per capita emissions of the poorest half of the population have declined since 1990, contrary to that of wealthier groups. Current emissions levels of the poorest half the population are close to per-capita 2030 climate targets in the US, the UK, Germany or France. In these countries, policy efforts should therefore be largely focused on reducing emissions levels of the top half of the population and in particular of the top 10%. In low-income and emerging countries, while certain groups will see their emissions levels rise in the coming decades, urgent action is needed to curb down emissions of the wealthy.
- While they officially report carbon emitted within their own territory, governments do not produce systematic data on the carbon imported in goods and services to sustain living standards in their country. Factoring-in emissions embedded in imports and exports (as we do in this study), European emission levels increase by around 25% and reduce reported emissions in China and Sub-Saharan Africa by around 10% and 20%, respectively.
- Since the industrial revolution, around 2500 billion tonnes of CO2 have been emitted by humankind. Based on current emissions rates, the remaining carbon budget to limit global warming to 2°C above preindustrial levels (that is, 900 billion tonnes of CO2) will be entirely depleted in 18 years. To limit global warming to 1.5°C, the remaining budget (300 billion tCO2) will be depleted in 6 years.
- Monitoring. Countries do not possess basic, up-to-date information to track carbon emissions inequalities. It is urgent to develop public monitoring systems to measure carbon emissions of individuals, with a particular focus on carbon emissions embedded in consumption and in investment portfolios.
- Reporting. Based on improved carbon inequality data, public deliberation could set clear targets in terms of emissions reductions per capita (not only in terms of national totals) and develop information systems enabling individuals to check the distance between their own emissions levels and national per capita targets. A systematic assessment of the beneficiaries and losers of climate policies should also be carried out by public authorities.
- Taxing. Climate policies have been disproportionately borne by low-income consumers over the past decades, in particular via carbon and energy taxes. More emphasis should be placed on wealthy polluters. This can be done via policy instruments targeting investments in polluting and fossil activities. Progressive wealth taxes on the ownership of polluting activities could accelerate divestments, reduce pollution levels of the wealthiest and generate much-need resources to scale-up investments in low-carbon infrastructures. Ultimately, the ownership and sale of assets associated to new fossil projects should be prohibited.
- Earmarking. Public actors must significantly scale-up their investments in low-carbon energy production infrastructures, transport and energy efficiency in order to ensure a fair transition. Overall, additional annual investments in the energy transition of around 2% of global GDP are needed (representing an additional $ 1800bn in 2021). A relatively modest progressive global wealth with a pollution top-up, such as the one presented in this study, could generate 1.7% of global income. A significant part of these revenues can be earmarked towards the green transition to finance climate investments without additional financial cost for low- and middle-income groups.
Contacts & Credits
- Lucas Chancel (Paris School of Economics; World Inequality Lab; Sciences Po)
This work benefitted from the support of the United Nations Development Programme.
- Latest version of the research article and its Appendix detailing the methodology of distributional carbon estimates
- See also the complementary Technical Note on the methodology for aggregate CO2 emissions series