This study examines the multiple dust storms that hit the eastern Mediterranean and Greece during March 2018, emphasizing on the atmospheric dynamics for their generation, the source regions, the dust-induced radiative forcing and the impacts on PM concentrations in Athens. In March 2018, several dust storms facilitated by increased cyclonicity in the western Europe/Mediterranean and by the Sharav cyclogenesis along the north African coast resulted in abnormal-high columnar aerosol loading and PM concentrations over Greece. The dusty days were associated with intense winds ->15 - 20 ms−1- from southwestern directions, triggered by cyclonic circulations over the central/eastern Mediterranean and troughs over Italy and the north African coast. Statistical analysis of the backward air-mass trajectories shows that the highest PM10 concentrations are related to dust sources in Libya, while Ceilometer profiles indicate thick dust plumes with highest intensity between the surface and 3 km over Athens. The monthly-averaged hourly PM10 concentrations at several stations in the Athens basin ranged from 37 μgm−3 to 53 μgm−3, while nine days exhibited PM10 daily-means above 50 μgm−3, characterized as dusty days. The PM10 concentrations in Athens maximized on 25–26 March -∼500 μgm−3 at hourly basis-, while the PM2.5 constitutes 38%–59% of PM10, indicating a dominance of coarse particles. Aerosol radiative forcing -ARF- estimates via the synergy of OPAC and SBDART models at three AERONET stations in Greece revealed significant impact of dust on radiation budget, with large -∼−40 W m−2 to −50 W m−2- decrease in surface solar radiation and an overall cooling effect at the top of atmosphere -∼−5 to −30 W m−2-. The atmospheric heating via the dust-aerosol absorption results in heating rates of ∼0.5 K day−1.

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