Continued global warming from aviation even under high ambition mitigation scenarios

Decarbonizing the aviation sector is a significant challenge. The International Civil Aviation Organization (ICAO) recently released long-term CO2-focused mitigation goals involving changes in fuel, efficiency improvements, and fossil jet fuel phase-out. The ultimate climate effect of these goals, however, was not assessed and moreover, the non-CO2 emissions were not accounted for. Here, we use the CICERO-SCM climate model and consider global aviation’s life cycle CO2 and non-CO2 emissions (NOx, SO2, H2O, and black carbon) to analyze total changes in global mean surface temperature. Results show that aviation-induced warming will increase to 0.10°C–0.12°C (0.07°C–0.15°C) by 2070, with the most ambitious scenario still more than doubling the present-day aviation-induced warming, despite full phase-out of fossil jet fuel by 2040 as per ICAO’s latest goal. A considerable, albeit uncertain, fraction of 2070 warming is attributed to non-CO2 effects. Our study underlines the need for consideration of non-CO2 impact reduction in parallel with the need for CO2 mitigation.