Dust life cycle (emission, transport and deposition) is strongly interlinked with atmospheric circulation and limate dynamics. This work focuses on dust (storm) properties and examining their dynamic meteorological conditions with trans-portations over the South West (SW) Asia. For the atmospheric and climatic conditions over SW Asia, the North Caspian Sea Pattern (NCP) was found to play an important role on modulating either the wind patterns or the recorded temperature and precipitation over SW Asia. Arid areas (deserts) in SW Asia contain active dust sources resulting in frequent and massive sand/dust storms, especially during the summer season. RegCM4 model simulations indicate that the intense northern Levar wind, the high surface heating and the valley-like characteristics of the region strongly affect the meteorological dynamics and the formation of a low-level jet that are strongly linked with dust exposures. Contrasting anomalies in MSLP between the Caspian Sea and Hindu Kush strengthens the northerly flow along the eastern Iranian borders (Levar wind), resulting in activation of the dust sources over the Sistan and in significantly larger dust outflows over the northern Arabian. Dust mobilization over SW Asia is controlled by contrasting meteorological regimes. For example, the Indian thermal low and the Levar wind are responsible for dust emissions over SW Asia. HYSPLIT back/forward-trajectory analysis at 500 m for air masses on the dust-storm days shows that they usually are originating from the east Caspian Sea and Hindukush and flow from Turkmenistan towards the south following an anti-clockwise direction at elevations usually below 2 km; they initially move southwards and then shift to east-northeast when they are approaching the Arabian Sea coast. This is the result of the influence of the local topography and formation of thermal low-pressure systems over the arid lands. It is found that the dust storms affect the central/south Arabian Sea and India, while they control the aerosol loading over the northernmost Arabian Sea. Aerosol Optical Depth (AOD) and the Infrared Difference Dust Index (IDDI) images, confirm the main pathways of the dust plumes and the importance of Sistan basin as one of the most active dust sources in southwest Asia. Analysis of airborne and soil dust samples shows that the dust mineralogy is dominated mainly by quartz (30–40%), calcite 18–23%), muscovite (10–17%), plagioclase (9–12%), chlorite (6%) and enstatite (3%), with minor components of olomite, microcline, halite and gypsum. The most important oxide compositions of the airborne and soil dust are SiO2, CaO, Al2O3, Na2O, MgO and Fe2O3, exhibiting similar percentages for dust and soil samples. The results suggest that a common dust source region can be inferred, which the eroded sedimentary environment in the extensive Hamoun dry lakes is laying to the north of Sistan.

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