Dust deposition from air with anomalous characteristics
A singular event related with the fall of a considerable amount of dust with anomalous characteristics is reported here, as well as the physicochemical characteristics of samples collected at the site in Lisbon—Portugal. The dust fall occurred during a rainy autumnal overnight and the geographic delimitation of the affected area, as well as the physical state in situ of the powder samples, are not compatible with the one that would be expected considering the climatic conditions registered at that time. The collected samples have been investigated, particularly by modern techniques involving nanoparticle analysis. The results prove that the samples have a very heterogeneous and granulated composition whose nanoparticle size distribution is bimodal (centered, respectively, about 90 and 120 nm) and containing some nanowhiskers and nanorods. Taking into account the official meteo data, it is likely that dust must have been transported by air and dried in the place (after rain) by unusual extremely localized-heat wave. However, the back trajectories software simulations point to a geographic source of clouds which soil chemical composition has no correlation with the chemical composition of the sample and where no industrial-relevant source is assigned.
KeywordsAtmospheric dust Dust precipitation Nanophysics Ultrafine particles Localized-heat wave
The author thanks CECIF association, in particular Fernando Silva who helped him to carry out the in situ collection of powder samples. Contributions from ICEMS center, and technical support from M.T. Brandao and Dias de Sousa enterprises are gratefully acknowledged, as well as Filipe Inok for software suggestions. Meteorological data provided by the national IPMA institute were very useful and so they are also acknowledged. Finally, the author also wishes to thank the financial support through the projects PTDC/FIS/67018/2006 and PEST (UID/EEA/00066/2013), CTS-UNINOVA.
- Bazzano A, Ardini F, Grotti M, Malandrino M, Giacomino A, Abollino O, Cappelletti D, Becagli S, Traversi R, Udisti R (2016) Elemental and lead isotopic composition of atmospheric particulate measured in the Arctic region (Ny-Ålesund, Svalbard Islands). Rend Fis Acc Lincei 27:73–84CrossRefGoogle Scholar
- Giardi F, Becagli S, Traversi R, Frosini D, Severi M, Caiazzo L, Ancillotti C, Cappelletti D, Moroni B, Grotti M, Bazzano A, Lupi A, Mazzola M, Vitale V, Abollino O, Ferrero L, Bolzacchini E, Viola A, Udisti R (2016) Size distribution and ion composition of aerosol collected at Ny-Ålesund in the spring–summer field campaign 2013. Rend Fis Acc Lincei 27:47–58CrossRefGoogle Scholar