This work examines a persistent dust event over the Middle East (29 June - 5 July 2011), the vertical dust cross-sections and associated radiative effects, via the synergy of satellite observations, reanalyses and two regional high-resolution models (WRF-Chem and RegCM4). The model s evaluation showed a generally better performance of WRF-Chem in aerosol optical depth (AOD) simulations, but with notable biases against satellite and reanalysis data. The dust storm started from the Tigris-Euphrates plains, passed over Kuwait, and affected the Persian Gulf and east Saudi Arabia. The dust plumes were further escalated with dust emissions from the Rub-Al-Khali and Oman Deserts, while they mixed over the Arabian Sea with dusty air masses coming from southwest Asia. Shamal wind over the alluvial Iraqi plains and the Persian Gulf, combined with strong monsoon southwesterlies over the Arabian Sea and northern Levar wind over SW Asia facilitated dust emissions from various sources. In addition, dust outflow from East Africa to Arabia caused a surface shortwave (SW) radiation reduction of ~100–110 W m− 2 in the southern Red Sea, Gulf of Aden and Oman shorelines. Over the northern Arabian Sea, south Red Sea and Gulf of Aden the net (SW + LW) surface radiative effect ranged from −60 to −80 W m−2. A thick dust plume caused higher SW radiative effects over the southern Caspian Sea (−170 W m−2), with a net forcing of −140 W m−2. The dust radiative cooling resulted in reduction in surface temperature (−1 °C to −2 °C) over the major dust-affected areas. Longwave (LW) radiative forcing (up to 50 W m−2) was simulated over the desert regions due to coarse dust. This study highlights notable differences in dust source functions, emission rates, and dust loading between the reanalysis, satellite datasets and model simulations, which may result in important biases in dust radiative effects.

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