Relative impact of roughness and soil texture on mineral dust emission fluxes modeling

Dust production models are widely used to estimate vertical fluxes of mineral aerosols over arid regions. Mineral dust fluxes emitted over western Africa represent one of the largest amount of aerosols in the atmosphere but the emission calculation remains highly uncertain. Several parameters are involved in the emissions calculations: among others, the surface and soil description is crucial. In atmospheric modeling, depending on the modelled area and the horizontal resolution, several surface and soil datasets are available and used. Some datasets are built merging satellite data and field campaigns specifically dedicated to this aerosol type: they are generally area limited. Some other datasets are less fine but available for the whole Earth, used for several model applications, including trends and climate studies. In this paper, different surface and soil databases are used to force the same dust production model. Mineral dust fluxes are calculated and compared in term of intensity and spatialization. It is shown that a combination of ERS satellite derived roughness length, of the USGS surface dataset and of the STATSGO-FAO the soil dataset, used with an explicit calculation of drag efficiency enables to estimates realistic mineral dust fluxes when compared to the LISA dataset, used as a reference and built with local measurements and analysis but restricted to the Saharan and Sahel regions.