Aerosol-Ozone correlation during Saharan Dust events in a Mediterranean Area

The dominant source of mineral dust for the Mediterranean Basin is the Saharan Desert. In weather conditions favourable to lift dust materials, the atmospheric circulation can transport dust particles over long distances from their point of origin. Fields campaign and modelling studies show an anti-correlation between aerosol and ozone concentration during Saharan Dust intrusions, since aerosols provide reactive surface where heterogeneous reactions can take place. In the middle of April 2002, a Saharan dust storm was blowing dust out over northern Africa and the Mediterranean Sea, all the way to Italy, as satellite images show. In this study the model system LM/DRAIS/MADEdust 1 has been used to simulate the meteorological situation and the transport and diffusion of Saharan Dust during the period April 9-14, 2002. In the MADEdust module the emission of dust particles is calculated using a parameterization which takes in account the relevant processes as saltation. To investigate the influence of mineral dust on the photochemical oxidant cycle, heterogeneous reactions between ozone and mineral dust have been implemented in a box model. Model results will be compared and agreements and differences will be discussed.