Impact of present and future aircraft emissions on atmospheric composition and radiative forcing of climate

International audienceDepending on the nature and the location of the emitted chemical agents, aircrafts contribute to warm or cool the climate. The chemical perturbation and the associated radiative forcing of carbon dioxide, ozone, methane, soot carbon (BC), sulphates, nitrates and organic carbon (OC) due to aircraft emissions have been calculated using five different global emission inventories using a carbon cycle compact climate change model and the climate-chemistry global model LMDz-ORCH-INCA. We found that the impact of the aviation CO2 emissions ranges from 45 ± 2mW/m² (2.5% of the total anthropogenic warming) for an ambitious mitigation strategy scenario (Factor 2) to 78 ± 4 mW/m² (2.5% of the total anthropogenic warming) for the least ambitious mitigation scenario of the study (ICAO based). Apart from CO2, the total radiative forcing related to aviation and modifications of gases and aerosols calculated in this work is negative and varies from -2.5mW/m² for the present scenario REACT4C (-3.6mW/m² in the case QUANTIFY_2000)