Retrieval of effective aerosol diameter from satellite observations

Abstract. Dust aerosol particle size plays a crucial role in determining dust cycle in the atmosphere and the extent of its impact on the other atmospheric parameters. The in-situ measurements of dust particle size are very costly, spatially sparse and time-consuming. This paper presents an algorithm to retrieve effective dust diameter using infrared band brightness temperature from SEVIRI (the Spinning Enhanced Visible and InfaRed Imager) on the Meteosat satellite. An empirical model was constructed that directly relates differences in brightness temperatures of 8.7, 10.8 and 12.0 μm bands to effective dust diameter using the Mie extinction efficiency factor. Three case studies are used to test the model. The results showed consistency between the model and in-situ aircraft measurements. A severe dust storm over the Middle-East is presented to demonstrate the use of the model. This algorithm is expected to contribute to filling the gap created by the discrepancies between the current size distributions retrieval techniques and aircraft measurements. Potential applications include enhancing the accuracy of atmospheric modelling and forecasting horizontal visibility and solar energy system performance over regions affected by dust storms.