This study examines the atmospheric dynamics that facilitated frequent and intense dust storms over the eastern Mediterranean in March 2018 via the synergy of satellite observations, ground-based measurements and reanalysis. The negative NAO phase in March 2018 caused cold weather conditions over the central/west Europe and strengthened the temperature gradient between cold European and warm North-African air at all levels from the surface up to 300 hPa. Large negative mean sea-level pressure -MSLP- anomalies over the western Mediterranean and south Europe strengthened the sea-level pressure and geopotential-height gradients across the Mediterranean, resulting in intensification of the westerlies over the west/central Mediterranean and the development of the Sharav cyclones along the north African coast. In addition, enhanced south/southwesterlies dominated over the eastern Mediterranean, associated with cyclonic conditions and intense dust storms on several days in March 2018. These meteorological conditions resulted in an increase of ~0.3–0.4 in AOD -~100%- and ~200 μg m−3 in surface dust concentration over parts of the eastern Mediterranean, compared to the mean March climatology. The vertical aerosol profiles over the eastern Mediterranean show a large increase in the mean extinction coefficient -~200 Mm−1- due to dust loading at altitudes between ~1 and 4 km. The dust radiative impact caused a significant decrease -~−10 Wm−2- in the incoming solar radiation under clear skies and in the latent and sensible energy fluxes over the eastern Mediterranean in March 2018, thus modulating the radiation/energy budget.

Keywords