Overshoot, potential air pollution co-benefits and food shortages

Achieving the 1.5°C target will entail a temporary overshoot, with peak temperatures potentially exceeding 1.7°C before declining towards the end of the century. This study examines how different economic growth patterns, energy transitions, and non-CO₂ mitigation strategies influence this trajectory. Our simulations reveal that achieving this target requires confining cumulative CO₂ emissions to 220–370 GtCO₂ by 2100, with a peak around 2060 of 530–650 GtCO₂. Key to success is the transition to net-zero CO₂ by 2060 and the implementation of Carbon Dioxide Removal (CDR) technologies. Effective reductions in CH₄ and N₂O are vital for minimizing additional warming. Significant co-benefits include improved air quality, with SO₂ and NOx emissions decreasing by 60–80 %, enhancing public health. However, aggressive climate policies and resulting high fertilizer prices may reduce food crop yields by up to 16.8 %, highlighting the need to integrate climate and agricultural strategies to balance emission reductions with food security and achieve long-term climate and sustainability goals. The deployment of CDR technologies with low land footprint, such as direct air capture, could help alleviate land-based trade-offs.