67a5ab46-4758-4ac6-91b3-01f836c1620c eng Ev-K2-CNR +39 035 3230511 +39 035 3230551 Via San Bernardino 145 Bergamo BG 24126 Italy metadata@evk2cnr.org http://www.evk2cnr.org/ 2012-03-07T15:06:20 ISO 19115:2003/19139 1.0 Convective transport of particulate matter in an Apennine valley: 2. Time variations in the columnar aerosol mass content and vertical profiles of aerosol mass concentration 2002-07-14T00:00:00 Atmospheric Research Volume 63 1–2 123-146 Atmospheric Research, 63, 2002 0169-8095 Multispectral sun-photometric measurements of aerosol optical depth were performed at five stations located at different altitudes from about 500 to 2165 m amsl in the Leo valley in the Apennines (Italy), on some clear-sky autumn days of 1981 and 1982. These measurements showed that the aerosol optical depth greatly increased during the morning at all stations due to the convective transport of particulate matter induced by the local upslope breezes. To evaluate the corresponding variations of the vertical mass loading of particulate matter, two continental and rural aerosol extinction models were determined: the first provides the spectral series of both volume and mass aerosol extinction coefficients at nine visible and near-infrared wavelengths for 27 aerosol particle size-distribution curves of Junge-type with values of the Ångström exponent ? varying between 0.15 and 1.99; the second is based on linear combinations of three monomodal particle size-distribution curves determined to give form to a nuclei mode, an accumulation mode and a coarse particle mode, respectively, whose particle number concentrations were defined to fit the values of ? characterising the spectral series of aerosol optical depth. These aerosol extinction models were used to obtain estimates of the columnar aerosol mass content at the five stations, finding values mostly ranging between 0.03 and 0.12 g m?2 at the two lower stations, 0.02 and 0.08 g m?2 at the two intermediate stations and between 0.01 and 0.03 g m?2 at the high-altitude Mt. Cimone station. The corresponding hourly mean percentage variations of the vertical aerosol mass loading were found to vary between a few percentages and nearly 100%, with median values ranging from 14% to 29% at the various stations. From these estimates, evaluations of the aerosol mass concentration were obtained within the four layers, varying from 15 to 160 ?g m?3 in the first layer, from 15 to 95 ?g m?3 in the second, from 10 to 60 ?g m?3 in the third and from 5 to 20 ?g m?3 in the fourth. Correspondingly, the hourly mean percentage variations were found to range between ?26% and +124% within the four layers, with median values gradually increasing from +4% to +20%, passing from the first to the fourth layer. Stefano Varani Institute of Atmospheric Sciences and Climate (ISAC) - CNR +39 0516399596 Via Gobetti 101 Bologna BO 40129 Italy S.Marani@isac.cnr.it www.isac.cnr.it Vito Vitale Institute of Atmospheric Sciences and Climate (ISAC) - CNR +39 0516399595 Via Gobetti 101 Bologna BO 40129 Italy V.Vitale@isac.cnr.it www.isac.cnr.it Claudio Tomasi Institute of Atmospheric Sciences and Climate (ISAC) - CNR +39 0516399594 Via Gobetti 101 Bologna BO 40129 Italy C.Tomasi@isac.cnr.it www.isac.cnr.it Elsevier Science Publishing Company nlinfo@sciencedirect.com http://www.elsevier.com/wps/find/homepage.cws_home Angelo Lupi Institute of Atmospheric Sciences and Climate (ISAC) - CNR +39 0516399592 Via Gobetti,101 Bologna BO 40129 Italy A.Lupi@isac.cnr.it www.isac.cnr.it https://geoportal.mountaingenius.org/geonetwork/srv/eng/resources.get?uuid=67a5ab46-4758-4ac6-91b3-01f836c1620c&fname=mountain_witness__s.png thumbnail png SHARE Vertical profiles of aerosol mass concentration Continental and rural aerosol extinction models Columnar aerosol mass content time-variations eng climatologyMeteorologyAtmosphere environment 6.62397 18.5144 36.6492 47.0946 http://www.sciencedirect.com/science/article/pii/S0169809502000376 WWW:LINK-1.0-http--partners Abstract:"Convective transport of particulate matter in an Apennine valley: 2. Time variations in the columnar aerosol mass content and vertical profiles of aerosol mass concentration" https://geoportal.mountaingenius.org/webapp/srv/en/resources.get?id=37685&fname=convective_transport_of_particulate_matter2_.pdf&access=private WWW:DOWNLOAD-1.0-http--download convective_transport_of_particulate_matter2_.pdf Full Text(pdf):"Convective transport of particulate matter in an Apennine valley: 2. Time variations in the columnar aerosol mass content and vertical profiles of aerosol mass concentration" "Convective transport of particulate matter in an Apennine valley: 2. Time variations in the columnar aerosol mass content and vertical profiles of aerosol mass concentration" Atmospheric Research, 63, 2002. Tomasi, C., Marani, S., Vitale, V., Lupi, A.