Investigating the role of new emission parameterizations in a regional model of the Saharan dust cycle

• Applicant: Dr. Benoit Laurent
• Subject Area: Atmospheric Science
• Term: from 2008 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 65492768

The scientific aim of this project is to investigate the Saharan mineral dust cycle and its links with the environment. Mineral dust is one of the major tropospheric aerosol components but its concentrations are highly variable in time and space. In fact, mineral dust emissions are sporadic and spatially heterogeneous and have to be described rigorously. Moreover, the dust cycle is sensitive to size dependent processes occurring during atmospheric transport, like dry and wet deposition. Recently, successful campaigns studied mineral dust over the North Africa (BoDEx, AMMA, and SAMUM). In the framework of SAMUM, recent modelling works point out the ability of the DES-LM-MUSCAT regional model to describe dust transport in the meso-scale and the regional dust radiative effect. Nevertheless, these first results indicate that a more complete study of the dust emissions (expertise on surface features and surface wind velocities), and dust size distribution near the source is needed to better simulate the Saharan mineral dust cycle. Such an expertise is not yet integrated in the modelling work of SAMUM. Our first objective is thus to test and improve the emissions and the size distribution of the DES-LM-MUSCAT model. The second objective is to simulate mineral dust cycle with DES-LM-MUSCAT model using the new developments for regional applications during the SAMUM period. The coupled dust-environment system at the sources, the present regional budgets of the Saharan dust emissions and depositions, and the radiative effect of the mineral dust will be then investigated.

• DFG Programme: Research Grants