Decoupling the cost estimations and equity implications of decarbonisation from carbon pricing

Existing long-term climate mitigation scenarios typically rely on carbon pricing to estimate macroeconomic impacts and equity implications of decarbonization, often projecting adverse distributional outcomes. However, substantial emissions reduction can also be achieved through non-carbon-pricing measures, raising concerns about the insights of these scenarios. Here, we evaluate to what extent non-carbon-pricing measures can mitigate such adverse side effects on macroeconomy and equity by developing and analysing scenarios with and without carbon pricing. We found that non-carbon-pricing decarbonization can reduce global adverse side effects on poverty, hunger risks, and domestic income inequality by 86%, 84%, and 90%, respectively, relative to conventional carbon-pricing-based scenarios. They stem from lower macroeconomic losses and modest increases in food and energy prices. Our findings indicate the great potential to moderate the concerns on the equity implications of climate change mitigation associated with carbon pricing and the need for improved policy representations in scenarios to better inform equitable and sustainable transitions.