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 A. Papayannis1, R. E. Mamouri1, V. Amiridis2, E. Remoundaki3, G. Tsaknakis1, P. Kokkalis1, I. Veselovskii4, A. Kolgotin4, A. Nenes5,6, and C. Fountoukis6 1National Technical University of Athens, Laser Remote Sensing Laboratory, Zografou, Greece,
[email protected] 2National Observatory of Athens, Institute for Space Applications and Remote Sensing, Athens, Greece 3National Technical University of Athens, School of Mining and Metallurgical Engineering, Zografou, Greece 4Physics Instrumentation Center for General Physics, Troitsk, 142190 Moscow, Russia 5Georgia Inst. of Tech., School of Earth and Atmos. Sc. and Chem. & Biomolecular Engineering, Atlanta GA, USA 6Institute of Chemical Engineering and High Temperature Chemical Processes, Foundation for Research and Technology Hellas (FORTH), Patras, Greece ABSTRACT A strong Saharan dust event occurred over the city of Athens, Greece (37.9oN, 23.6oE) between 27 March and 3 April 2009, was followed by a synergy of three instruments: a 6-wavelength Raman lidar, a CIMEL sun-sky radiometer and the MODIS sensor. The BSC-DREAM model was used to forecast the dust event and to simulate 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 lidar only during the cloud-free 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. The aerosol optical depth (AOD) values derived from the CIMEL ranged from 0.33-0.91 (355 nm) to 0.18-0.60 (532 nm), 1 while the lidar ratio (LR) values retrieved from the Raman lidar ranged within 75-100 sr (355 nm) and 45-75 sr (532 nm).