To meet ambitious climate targets, the aviation sector needs to neutralize CO₂ emissions and reduce non-CO₂ climatic effects. Despite being responsible for approximately two-thirds of aviation’s impacts on the climate, most of aviation non-CO₂ species are currently excluded from climate mitigation efforts. Here we identify three plausible definitions of climate-neutral aviation that include non-CO₂ forcing and assess their implications considering future demand uncertainty, technological innovation and CO₂ removal. We demonstrate that simply neutralizing aviation’s CO₂ emissions, if nothing is done to reduce non-CO₂ forcing, causes up to 0.4 °C additional warming, thus compromising the 1.5 °C target. We further show that substantial rates of CO₂ removal are needed to achieve climate-neutral aviation in scenarios with little mitigation, yet cleaner-flying technologies can drastically reduce them. Our work provides policymakers with consistent definitions of climate-neutral aviation and highlights the beneficial side effects of moving to aircraft types and fuels with lower indirect climate effects.

为了实现雄心勃勃的气候目标，航空部门需要中和 CO ₂排放并减少非 CO ₂气候影响。尽管航空业对气候造成的影响约占三分之二，但大多数航空业非 CO ₂物种目前被排除在气候减缓工作之外。在这里，我们确定了气候中和航空的三个合理定义，包括非 CO ₂强迫，并在考虑未来需求不确定性、技术创新和 CO ₂去除的情况下评估其影响。我们证明，如果不采取任何措施减少非CO _{2排放，只需中和航空业的 CO 2排放}强迫，导致高达 0.4 °C 的额外升温，从而影响 1.5 °C 的目标。我们进一步表明，在几乎没有缓解措施的情况下，实现气候中和航空需要大量的 CO _{2去除率，但更清洁的飞行技术可以大大减少它们。}我们的工作为政策制定者提供了对气候中和航空的一致定义，并强调了转向具有较低间接气候影响的飞机类型和燃料的有益副作用。