The Sistan, located in the Iran-Afghanistan-Pakistan region belongs to the “desert dust belt” that extends from the west coast of North Africa, over the Middle east, Central and South Asia, to China [1]. It is considered as one of the most active dust source regions in South west Asia. The specificity of the Sistan region is its limited spatial extent, its intense satellite signal and its complexity resulting from its rough topography, at the junction of basins and deserts. Thus, the region is associated with a complex wind pattern, strongly constrained by this topography, which controls the dust emission and transport. In spite of the local but intense signature in satellite observations of dust emissions and frequent dust storms, this dust source zone is relatively unknown. A consequence of the complex geographic situation of the Sistan region is the poorly availableground-basedmeasurementsofaerosolsproperties,exceptthoseprovidedbymeteorologicalstations(especially visibility and wind measurements available in Zabol and other stations in Iran and Pakistan). The nearest AERONET station is the one of Karachi in Pakistan. So, satellites observations and modeling are complementary tools to study and to understand dust emission and transport from Sistan sources. In this work, we present two components: first part is a climatological analysis of satellite observations over the 2007-2016periodbasedonAODderivedfromMODIS(DeepBluecombinedtoDarkTargetproduct)andAerosol Index from OMI; the second part is the RAMS (Regional atmospheric modeling system) analysis of desert dust emission and transport from the Sistan region. Our objectives are to identify the most intense dust events during the time period of the last ten years; to study their seasonal and inter-annual variability; to validate numerical simulationsofdusteventsfrommeso-scalemodelinunderstandingemissionandtransportofdustprocessesinthe specific Sistan region. Complementary dust observations from MSG/IDDI will help to characterize specific dust events that will be investigated in details. This analysis is part of a LEFE/INSU project [2] that combines model simulations with ground-based and satellite measurements to study desert dust emission and transport from the Sistan.

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