The western Mediterranean basin as an aged aerosols reservoir. Insights from an old-fashioned but efficient radiotracer. (September 2016)

• Record Type: Journal Article
• Authors: Brattich, E.; Hernández-Ceballos, M.A.; Orza, J.A.G.; Bolívar, J.P.; Tositti, L.
• Is Part Of: Atmospheric environment. Volume 141(2016)
• Page Start: 481
• Page End: 493
• Publication Date: 2016-09
• Subjects: 210Pb -- PM10 -- Radiotracer -- Source identification -- Residence time -- PSCF -- Mediterranean basin -- Saharan dust; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2016.07.022
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: The long-term contemporary 210 Pb time series acquired during the period 2004–2011 at two distant sites of different altitude in the Mediterranean basin, El Arenosillo (40 m a.s.l. in southwestern Spain) and Mt. Cimone (2165 m a.s.l. in northern Italy), are analyzed and compared. Besides being considered a tracer of continental air masses, 210 Pb radionuclide is also a proxy of fine stable aerosol. For this reason, the measurements of PM10 mass concentrations collected at the same time and the corresponding 210 Pb/PM10 ratio at the two sites are considered to gain better insights into the origin and size of the particles. Three statistical trajectory methods are applied to identify and characterize the 210 Pb source regions at the two sites. The three methods yield similar outcomes in the source identification, which strengthens the robustness of our results. In addition to the importance of the transport from areas of continental Europe, this study highlights the relevant role of the Mediterranean Sea as a major 210 Pb reservoir layer associated to the aged air masses that accumulate in the western Mediterranean basin. The analysis of the sources points out the significant influence of northern Africa to 210 Pb increases at both sites as well, even though the most intensive episodes are not of Saharan origin. Highlights: Long-term 210 Pb concentrations at two sites in the Mediterranean basin. Comparison of 210 Pb and PM10 sources at two distant sites of different altitude. Influence of Saharan dust transport on 210 Pb concentrations. Relevant role of the Mediterranean sea as a 210 Pb reservoir layer. Importance of aged air masses on 210 Pb increases in the western Mediterranean.