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; Mamouri, RE; Amiridis, V; Remoundaki, E; Tsaknakis, G; Kokkalis, P; Veselovskii, I; Kolgotin, A; Nenes, A; Fountoukis, C

dc.contributor.author	Papayannis, A	en
dc.contributor.author	Mamouri, RE	en
dc.contributor.author	Amiridis, V	en
dc.contributor.author	Remoundaki, E	en
dc.contributor.author	Tsaknakis, G	en
dc.contributor.author	Kokkalis, P	en
dc.contributor.author	Veselovskii, I	en
dc.contributor.author	Kolgotin, A	en
dc.contributor.author	Nenes, A	en
dc.contributor.author	Fountoukis, C	en
dc.date.accessioned	2014-03-01T02:11:51Z
dc.date.available	2014-03-01T02:11:51Z
dc.date.issued	2012	en
dc.identifier.issn	16807316	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/29962
dc.subject.other	aerosol composition	en
dc.subject.other	aerosol property	en
dc.subject.other	chemical property	en
dc.subject.other	dust	en
dc.subject.other	lidar	en
dc.subject.other	mineralogy	en
dc.subject.other	MODIS	en
dc.subject.other	optical depth	en
dc.subject.other	organic carbon	en
dc.subject.other	particulate matter	en
dc.subject.other	radiometer	en
dc.subject.other	refractive index	en
dc.subject.other	sulfate	en
dc.subject.other	troposphere	en
dc.subject.other	vertical profile	en
dc.subject.other	water vapor	en
dc.subject.other	Athens [Attica]	en
dc.subject.other	Attica	en
dc.subject.other	Greece	en
dc.title	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	en
heal.type	journalArticle	en
heal.identifier.primary	10.5194/acp-12-4011-2012	en
heal.identifier.secondary	http://dx.doi.org/10.5194/acp-12-4011-2012	en
heal.publicationDate	2012	en
heal.abstract	A strong Saharan dust event that occurred over the city of Athens, Greece (37.9° N, 23.6° E) 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), while the lidar ratio (LR) values retrieved from the Raman lidar ranged within 75-100 sr (355 nm) and 45-75 sr (532 nm). Inside a selected dust layer region, between 1.8 and 3.5 km height, mean LR values were 83 ± 7 and 54 ± 7 sr, at 355 and 532 nm, respectively, while the Ångström-backscatter-related (ABR355/532) and Ångström-extinction-related (AER355/532) were found larger than 1 (1.17 ± 0.08 and 1.11 ± 0.02, respectively), indicating mixing of dust with other particles. Additionally, a retrieval technique representing dust as a mixture of spheres and spheroids was used to derive the mean aerosol microphysical properties (mean and effective radius, number, surface and volume density, and mean refractive index) inside the selected atmospheric layers. Thus, the mean value of the retrieved refractive index was found to be 1.49( ± 0.10) + 0.007( ± 0.007)i, and that of the effective radiuses was 0.30 ± 0.18 μm. 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 provide a possible aerosol composition consistent with the retrieved refractive index values. Thus, the inferred chemical properties showed 12-40% of dust content, sulfate composition of 16-60%, and organic carbon content of 15-64%, indicating a possible mixing of dust with haze and smoke. PM10 concentrations levels, PM10 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. © 2012 Author(s).	en
heal.journalName	Atmospheric Chemistry and Physics	en
dc.identifier.doi	10.5194/acp-12-4011-2012	en
dc.identifier.volume	12	en
dc.identifier.issue	9	en
dc.identifier.spage	4011	en
dc.identifier.epage	4032	en