In Situ Samplings and Remote Sensing Measurements to Characterize Aerosol Properties over Southeast Italy

Abstract Ground-based particulate matter (PM) samplers, an XeF Raman lidar operating in the framework of the European Aerosol Research Lidar Network (EARLINET), and a sun/sky radiometer operating in the framework of the Aerosol Robotic Network (AERONET) have been used to characterize vertical profiles, optical and microphysical properties, and chemical composition of aerosols during the 29 June–1 July 2005 dust outbreak that occurred over the central-eastern Mediterranean. Aerosol backscatter coefficient, total depolarization, and lidar ratio vertical profiles revealed that a well-mixed dust layer extending from ∼0.5 to 6 km was present over southeastern Italy on 30 June. Sun/sky radiometer measurements revealed a bimodal lognormal size distribution during all measurement days. The particle volume distribution was found to be well correlated either to the PM mass distribution measured at ground by a seven-stage cascade impactor and to the fine to total suspended PM mass ratio measured by ground-based PM samplers. Scanning electron microscopy and ion chromatography analyses on PM samples revealed that coarse-mode aerosols were mainly made of carbonate, aluminum-silicate, and sea salt particles. Carbon, sulfate, and nitrate particles were the main components of fine-mode aerosols representing more than 50% of the total aerosol load; the significant role of fine-mode anthropogenic particles during a dust event is highlighted. Finally, the potential capabilities of complementary measurements by passive and active remote sensing techniques and in situ observations to retrieve the vertical distribution of the particle number and mass concentration are analyzed and discussed

Relation of air mass source regions to PM10 mass concentrations using back trajectories

Abstract T06A195

Advection patterns and composition of TSP and PM2.5 samples over south-east Italy

24-hour Total Suspended Particulate (TSP) matter and PM2.5 samples have simultaneously been collected at a subrban site of South-East Italy to investigate the dependence of TSP and PM2.5 mass concentrations on long-range transported air masses

Composition of Fine and Coarse Particles in a coastal site of the Central Mediterranean: carbonaceous specie contributions

Total Suspended Particulate (TSP) and PM2.5 samples simultaneously collected at a coastal site (40.4°N; 18.1°E) in the central Mediterranean are analyzed to investigate the relative role of ions (Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, Ca2+) and carbonaceous species in the fine (PM2.5) and coarse (TSP-PM2.5) sampled mass and contribute to the characterization of the Central Mediterranean particulate. A methodology is described to determine carbonate carbon (CC), organic carbon (OC), and elemental carbon (EC) levels from Thermal Optical Transmittance (TOT) measurements since carbonate particles may significantly contribute to the Mediterranean particulate. We have found that CC levels vary up to 1.7 $\mu$g/m3 and 0.8 $\mu$g/m3 in the coarse and fine fraction, respectively. OC and EC levels vary up to 3.0 $\mu$g/m3 and 1.5 $\mu$g/m3, respectively in the coarse fraction, and vary within the 2.2-10 $\mu$g/m3 and 0.5-5 $\mu$g/m3 range, respectively in the fine fraction. Hence, it is shown that OC levels may be quite overestimated mainly in the coarse fraction, if the CC contribution is not accounted for. CO32- levels (calculated from CC concentrations) account on average for 6% and 10% of the fine (PM2.5) and coarse (TSP-PM2.5) sampled mass, respectively and allow balancing the anion deficit resulting from the ionic balance of ions detected by ion-chromatography (IC). Total carbon TC = (OC+EC) accounts on average for 29% and 6% of the fine and coarse mass, respectively. IC ions account for 38% and 17% of the fine and coarse mass, respectively. OC, EC, SO42-, NH4+, and K+ are the major components in the fine fraction, accounting on average for 84% of the analyzed PM2.5mass. Marine- and crust-originated ions (Cl-, Mg2+, Na+, Ca2+, CO32-) and NO3- are mainly in the coarse fraction and represent on average 83% of the analyzed coarse mass. A discussion on the main reactions leading to the loss of ammonium particulate in the coarse fraction is provided. It is also shown that the Cl-/Na+ ratio varies within the 0.1-0.8 and 0.0-1.0 range in the fine and coarse particle fraction, respectively for the occurrence of Cl depletion processes

Composition of fine and coarse particles in a coastal site of the central Mediterranean: Carbonaceous species contributions

Total Suspended Particulate (TSP) and PM2.5 samples simultaneously collected at a coastal site (40.4°N; 18.1°E) in the central Mediterranean are analyzed to investigate the relative role of ions (Cl -, NO3-, SO42-, Na +, NH4+, K +, Mg 2+, Ca 2+) and carbonaceous species in the fine (PM2.5) and coarse (TSP-PM2.5) sampled mass. A methodology is described to determine carbonate carbon (CC), organic carbon (OC), and elemental carbon (EC) levels from Thermal Optical Transmittance (TOT) measurements since carbonate particles may significantly contribute to the Mediterranean particulate. We have found that CC levels vary up to 1.7 μg m -3 and 0.8 μg m -3 in the coarse and fine fraction, respectively. OC and EC levels vary up to 3.0 μg m -3 and 1.5 μg m -3, respectively in the coarse fraction, and vary within the 2.2-10 μg m -3 and 0.5-5 μg m -3 range, respectively in the fine fraction. Hence, OC levels may be overestimated mainly in the coarse fraction, if the CC contribution is not accounted for. CO32- levels (calculated from CC concentrations) account on average for 6% and 10% of the fine and coarse mass, respectively and allow balancing the anion deficit resulting from the ionic balance of ions detected by ion chromatography (IC). Total carbon TC = (OC + EC) accounts on average for 29% and 6% of the fine and coarse mass, respectively. IC ions account for 38% and 17% of the fine and coarse mass, respectively. OC, EC, SO42-, NH4+, and K + are the major components in the fine fraction, accounting on average for 84% of the analyzed PM2.5 mass. Marine- and crust-originated ions (Cl -, Mg 2+, Na +, Ca 2+, CO32-) and NO3- are mainly in the coarse fraction and represent on average 83% of the analyzed coarse mass

Advection patterns and composition of TSP and PM2.5 samples over south-east Italy

24-hour Total Suspended Particulate (TSP) matter and PM2.5 samples have simultaneously been collected at a subrban site of South-East Italy to investigate the dependence of TSP and PM2.5 mass concentrations on long-range transported air masses

Ionic and elemental composition of TSP, PM10, and PM2.5 samples collected over South-East Italy

24-hour TSP, PM10, and PM2.5 samples collected from June to October 2004 at a suburban site of south-east Italy, in the Central Mediterranean, have been analyzed to investigate the dependence of mass concentrations and of ionic (F-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, Ca2+) and elemental (Ti, Al, Si, Fe, Mn, Cu, Zn, Pb, Cd) components on particulate matter (PM) fraction