Unequal Emissions, Unequal Impacts: How High-Income Groups Disproportionately Contribute to Climate Extremes Worldwide

One of the fundamental injustices of climate change is that those least responsible often bear the brunt of its impacts. This injustice persists not only between countries but also on the individual level within societies. Here, we assess how greenhouse gas emissions from consumption and investments attributable to the wealthiest population groups from 1990 to 2019 have influenced present-day (2020) global mean temperature levels as well as monthly temperature and potential drought extremes. We combine emission inequality data with an emulator-based modelling framework, enabling a systematic attribution of changes in regional extremes worldwide. We find that the top 10% wealthiest individuals globally contributed about 6.5 times the global average to global warming (0.40°C ± 0.16°C), the top 1% even 20 times the average (0.12°C ± 0.05°C). These disproportionate contributions further amplify for extreme events, with the top 10% contributing about 7 times more to the emergence of 1-in-100 year heat and potential drought events than the global average (11.5 ± 3.9 and 4.7 ± 2.8 additional occurrences), the top 1% 25 times more (4.0 ± 1.3 and 1.7 ± 0.9 additional occurrences). Emissions from the the wealthiest 10% in the United States and China, the two largest greenhouse gas emitters, are associated with a two- to three-fold increase in the frequency of heat and drought extremes across vulnerable regions. Quantifying the relationship between wealth disparities and climate change impacts can assist the discourse on climate equity and justice.