The CHIMERE v2020r1 online chemistry-transport model

Abstract

Abstract. The CHIMERE v2020r1 model replaces the v2017r5 version and provides numerous novelties. The most important of which is the online coupling with the WRF meteorological model, via the OASIS3-MCT external coupler. The model can still be used in offline mode; the online mode enables taking into account the direct and indirect effects of aerosols on meteorology. This coupling also enables using the meteorological parameters with sub-hourly time-steps. Some new parameterizations are implemented to increase the model performance and the user's choices: DMS emissions, additional schemes for SOA formation with VBS and H2O, improved schemes for mineral dust, biomass burning and sea-salt emissions. The NOx emissions from lightning is added. The model also includes the possibility to use the splitting-operator integration technique. The subgrid scale variability calculation of concentrations due to emission activity sectors is now possible. Finally, a new vertical advection scheme has been implemented, able to simulate more correctly long-range transport of thin pollutants plumes.