Simulation of the tropical cyclone Dumile in Meso-NH with a 2-moment microphysics scheme coupled with an aerosol scheme with an explicit emission of sea salt and the MACC analyses of ECMWF
Résumé
The main issue in front of the cyclone threat is to forecast both the track, the intensity and the main consequences (wind, precipitation, storm surge and swell) associated to a tropical cyclone. The past decade has been marked by significant advances in numerical weather prediction of cyclones, which have greatly contributed to the steady decrease of forecast track errors. However, the intensity forecasting remains a major issue in scientific research. The key role of cloud microphysics and aerosols on the structure and intensity of tropical storms has been recently underlined.A 2-moment microphysics scheme (LIMA ; Vié et al., 2015) is being coupled to an aerosol scheme (ORILAM ; Tulet et al., 2005) in the French mesoscale model Meso-NH. Aerosols are initialized by MACC analysis from ECMWF which also monitor the lateral boundary conditions of the aerosol fields (prognostic variables). A parameterization of the emission of sea salt aerosol is implemented as the main source of cloud condensation nuclei in the context of the South-West Indian Ocean.A first evaluation of this aerosol-cloud-microphysics coupling will be done through a simulation of the tropical cyclone Dumile that passed next to La Réunion in January 2013. Available observations (CALIPSO, CLOUDSAT, TRMM and METEOSAT satellites, ground radar and observations from the Maïdo observatory and Meteo-France ground stations) will be used to validate the simulation. The sensitivity of the system structure and intensity to the aerosol type and concentration will be analyzed.