Improving aviation aerosol scavenging representation in LMDZ-OR-INCA model

The radiative forcing of aviation aerosol-cloud interactions remains very uncertain. Its quantification relies on climate models. One of the main drivers of aerosol concentrations and long-range vertical and horizontal transport in climate models is wet scavenging, which can be parameterised in different ways with several tunable parameters. In this work, we use the LMDZ-OR-INCA climate to investigate the impact of different scavenging parameterisations on aerosol transport, using regional and seasonal vertical profiles obtained from ATom and HIPPO airborne measurements to discriminate between parameterisations. Results show that the residence time and the mass budgets of BC from all sources are both significantly influenced by the scavenging parameterisation. Moreover, the ability of a BC scavenging parameterisation to simulate vertical aerosol concentration profiles depends on geographical location, altitude and season. Near-surface aerosol concentrations, mainly due to Landing and Take-off Operations (LTO), are also affected by the choice of a wet scavenging parameterisation. Results suggest it may be possible to design a new scavenging routine for LMDZ-OR-INCA model to better represent the long-range transport of aviation aerosols and reduce uncertainties in aviation aerosol-cloud interaction radiative forcing.