ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-7185-2011 Simulation of the mineral dust content over Western Africa from the event to the annual scale with the CHIMERE-DUST model Schmechtig C. 1 Marticorena B. 1 Chatenet B. 1 Bergametti G. 1 Rajot J. L. 2 Coman A. 1 LISA, UMR7583, CNRS, Universités Paris Est-Paris Diderot, Créteil, France IRD-UMR 211 BIOEMCO, Niamey, Niger 22 07 2011 11 14 7185 7207 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/7185/2011/acp-11-7185-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/7185/2011/acp-11-7185-2011.pdf

The chemistry and transport model CHIMERE-DUST have been used to simulate the mineral dust cycle over the Sahara in 2006. Surface measurements deployed during the AMMA field campaign allow to test the capability of the model to correctly reproduce the atmospheric dust load and surface concentrations from the daily to the seasonal time-scale. The simulated monthly mean Aerosol Optical Depths (AOD) and surface concentrations are significantly correlated with the measured ones. The simulated daily concentrations and hourly AOD are in the same range of magnitude than the observed ones despite relatively high simulated dust emissions. The level of agreement between the simulations and the observations has been quantified at different time scales using statistical parameters classically used to evaluate air quality models. The capability of the model to reproduce the altitude of the dust transport was tested for two contrasted cases of low and high altitude transport. These results highlight the sensitivity of the simulations to the surface winds used as external forcing and the necessity to further constrain the dust mass budget at the regional scale.

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