Numerical simulations of the urban atmosphere of Marseille during the UBL/ESCOMPTE experiment that took place in June?July 2001 are presented. The atmospheric model is the SUBMESO version with grid-nesting, coupled to the urban soil model SM2U, with new parameterisations for sea surface and lateral boundary forcing. Urban characteristics are reproduced with a high degree of realism through a land-use/morphology analysis of Marseille urban fabric. The simulations of the intense observation period IOP2b, characterised by land/sea-breeze regimes, are confronted against measurements to validate the set of models. The 25 June meteorological situation is analysed in detail and a sensitivity study to the city representation is conducted to highlight the city influence on the flow dynamics, especially the urban heat island process and the wind field alterations.
Keywords: urban boundary layer, numerical simulation, topography, grid nesting, soil model, urban classification, turbulent fluxes, sea breezes, urban heat island, France, Marseille, atmospheric modelling, flow dynamics, air quality, air pollution, dispersion modelling, pollutant dispersion, sea-city interactions