ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-11-25473-2011 Optical-microphysical properties of Saharan dust aerosols and composition relationship using a multi-wavelength Raman lidar, in situ sensors and modelling: a case study analysis Papayannis A. 1 Mamouri R. E. 1 Amiridis V. 2 Remoundaki E. 3 Tsaknakis G. 1 Kokkalis P. 1 Veselovskii I. 4 Kolgotin A. 4 Nenes A. 5 6 Fountoukis C. 6 National Technical University of Athens, Laser Remote Sensing Laboratory, Zografou, Greece National Observatory of Athens, Institute for Space Applications and Remote Sensing, Athens, Greece National Technical University of Athens, School of Mining and Metallurgical Engineering, Zografou, Greece Physics Instrumentation Center for General Physics, Troitsk, 142190 Moscow, Russia Georgia Inst. of Tech., School of Earth and Atmos. Sc. and Chem. & Biomolecular Engineering, Atlanta GA, USA Institute of Chemical Engineering and High Temperature Chemical Processes, Foundation for Research and Technology Hellas (FORTH), Patras, Greece 12 09 2011 11 9 25473 25516 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/11/25473/2011/acpd-11-25473-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/25473/2011/acpd-11-25473-2011.pdf

A strong Saharan dust event occurred over the city of Athens, Greece (37.9° N, 23.6° E) between 27 March and 3 April 2009. The BSC-DREAM8b model was used to forecast the dust event and to provide the vertical profiles of the aerosol concentration. Due to mixture of dust particles with low clouds during most of the reported period, the dust event could be followed by the National Technical University of Athens (NTUA) 6-wavelength Raman lidar system only during the unclouded day of 2 April 2009. The lidar data obtained were used to retrieve the vertical profile of the optical (extinction and backscatter coefficients) properties of aerosols in the troposphere. Additionally, a retrieval technique representing dust as a mixture of spheres and spheroids was used to derive the mean aerosol dust microphysical properties (mean and effective radius, number, surface and volume density, and mean refractive index) in different layers between 1.8 and 3.5 km a.s.l. The final data set of the aerosol optical and microphysical properties along with the water vapor profiles obtained by Raman lidar were incorporated into the ISORROPIA II model to infer an in situ aerosol composition consistent with the retrieved refractive index values. PM<sub>10</sub> concentrations levels, PM<sub>10</sub> composition results and SEM-EDX (Scanning Electron Microscope-Energy Dispersive X-ray) analysis results on sizes and mineralogy of particles from samples during the Saharan dust transport event were used to evaluate the retrieval.

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