dot
Detailansicht
Katalogkarte GBA
Katalogkarte ISBD
Suche präzisieren
Drucken
Download RIS
Hier klicken, um den Treffer aus der Auswahl zu entfernen
Titel The formation and growth of ultrafine particles in two contrasting environments: a case study
VerfasserIn  Sobhan Kumar Kompalli, S. Suresh Babu, K. Krishna Moorthy, Mukunda M. Gogoi, Vijayakumar S. Nair, Jai Prakash Chaubey
Medientyp Artikel
Sprache Englisch
ISSN 0992-7689
Digitales Dokument URL
Erschienen In: Annales Geophysicae ; 32, no. 7 ; Nr. 32, no. 7 (2014-07-22), S.817-830
Datensatznummer 250121083
Publikation (Nr.) Volltext-Dokument vorhandencopernicus.org/angeo-32-817-2014.pdf
 
Zusammenfassung
Formation of ultrafine particles and their subsequent growth have been examined during new particle formation (NPF) events in two contrasting environments under varying ambient conditions, one for a tropical semi-urban coastal station, Trivandrum, and the other for a high-altitude free-tropospheric Himalayan location, Hanle. At Trivandrum, NPF bursts took place in the late evening/night hours, whereas at Hanle the burst was a daytime event. During the nucleation period, the total number concentration reached levels as high as ~ 15 900 cm−3 at Trivandrum, whereas at Hanle, the total number concentration was ~ 2700 cm−3, indicating the abundant availability of precursors at Trivandrum and the pristine nature of Hanle. A sharp decrease was associated with NPF for the geometric mean diameter of the size distribution, and a large increase in the concentration of the particles in the nucleation regime (Dp < 25 nm). Once formed, these (secondary) aerosols grew from nucleation (diameter Dp < 25 nm) to Aitken (25 ≤ Dp ≤ 100 nm) regime and beyond, to the accumulation size regimes (100 ≤ Dp ≤ 1000 nm), with varying growth rates (GR) for the different size regimes at both the locations. A more rapid growth ~ 50 nm h−1 was observed at Trivandrum, in contrast to Hanle where the growth rate ranged from 0.1 to 20 nm h−1 for the transformation from the nucleation to accumulation – a size regime that can potentially act as cloud condensation nuclei (CCN). The faster coagulation led to lifetimes of < 1 h for nucleation mode particles.
 
Teil von