Screenshot with the title and abstract of the paper. Abstract As the remaining carbon budget continues to dwindle, economic growth strains efforts to limit global warming to 1.5 °C. Reducing unnecessary production and consumption in high-income regions and among the wealthy, and organising production more around human needs and human well-being, may alleviate pressures on technology-driven decarbonisation strategies. We employ a modified integrated assessment model to explore the interaction between converging per-capita consumption, climate policy stringency and equity. Our pathways demonstrate that lower-consumption futures are associated with substantially lower warming, 0.3–1.1 °C across different carbon price trajectories, relative to high-consumption futures. Comparatively, global convergence of incomes between regions has a small influence on global temperature outcomes (<±0.1 °C). These findings indicate that reducing high per-capita consumption in high-income regions is a primary lever for achieving futures with equitable and decent living standards while meeting global climate targets. While such transformations may face political challenges, our scenarios suggest that unconstrained growth futures make it considerably harder to remain within safe climate limits.

Figure 1 of the paper. Legend: a Five distinct future archetypes emerge from the 36 modelled futures, where lines represent income per capita for each region across the study years. b Year-2100 temperature anomaly outcomes. Values refer to a 1-in-2 chance of not being transgressed by average global temperature anomalies. Roman numerals refer to the five future archetypes (I degrowth relevant, II Global South catch-up, III unequal post-growth, IV current affairs, V SSP2 narrative). Carbon prices shown are the population-weighted averages for the three carbon price scenarios: 0 (no carbon price), 60 (US$ t−1 CO2; C6‑consistent carbon price, 3 °C, >50%); 287 (US$ t−1 CO2; C4‑consistent carbon price, 2 °C, >50%); Carbon price trajectories are in Supplementary Fig. 1. Data for Fig. 1b are in Supplementary Table 1.

Figure 3 of the paper. Legend: a–l show 2020–2100 trajectories of useful energy per capita (GJ cap⁻¹) for the 11 MESSAGEix regions (colours in legend), across 12 combinations of global average consumption (̄c = 5, 10, 20, 50 k US$ cap⁻¹) and interregional Gini index (0, 0.25, 0.5). Results are for C4‑consistent (2 °C, >50%) carbon prices (for no and C6‑consistent (3 °C, >50%) carbon price settings in Supplementary Fig. 8 & 9). Comparison is against the Low-Useful-Energy9 value of 15–41 GJ cap−1 (purple band) and the Decent-Living Useful Energy45 range of 10–14 GJ cap−1 (blue band). Region acronyms: NAM North America, LAM Latin America & the Caribbean, WEU Western Europe, EEU Central & Eastern Europe, FSU Former Soviet Union, CPA Centrally Planned Asia & China, PAO Pacific OECD, PAS Other Pacific Asia, SAS South Asia, MEA Middle East & North Africa, AFR Sub-Saharan Africa. Data are provided in Source Data.