Long-term quantitative field study of New Particle Formation (NPF) events as a source of Cloud Condensation Nuclei (CCN) in the urban background of Vienna

Autor(en)

Carmen Dameto de España, A. Wonaschuetz, G. Steiner, B. Rosati, A. Demattio, H. Schuh, R. Hitzenberger

Abstrakt

Many studies have indicated New Particle Formation (NPF) events as an

important source of CCN in the atmosphere. However, most of these

studies are based on indirect determination of CCN concentrations or

were of rather short duration. In this study, we present long-term

measurements of CCN concentrations and particle number size

distributions performed in the urban background of Vienna, Austria,

spanning a period of two years. NPF events occurred on 70 of the 539

measurement days. For 38 of these events, concurrent CCN concentrations

(measured at 0.5% supersaturation) are available. Direct comparisons of

absolute CCN concentrations before and after an event, however, are

inconclusive as other influences can lead to changes in CCN

concentrations. In this study, we developed criteria to take local

emissions of ultrafine particles, atmospheric mixing conditions and

changes in air mass into account. A new normalization procedure

(CCN/PM2.5) is introduced to account for dilution and concentration

effects due to changes in boundary layer height. Other possible

influences, such as weather conditions and traffic emissions were

accounted for by tracking wind direction and velocity, as well as black

carbon (BC) mass concentrations. On 15 event days, all criteria to

exclude other influences were met. On 14 days, NPF was found to be a

source of CCN (at 0.5% supersaturation), with concentration increases by

up to 143%.

Organisation(en)

Aerosolphysik und Umweltphysik

Externe Organisation(en)

Leopold-Franzens-Universität Innsbruck, Universität Wien

Journal

Atmospheric Environment

Band

164

Seiten

289-298

Anzahl der Seiten

10

ISSN

1352-2310

DOI

https://doi.org/10.1016/j.atmosenv.2017.06.001

Publikationsdatum

09-2017

Peer-reviewed

Ja

ÖFOS 2012

103037 Umweltphysik, 103039 Aerosolphysik

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeine Umweltwissenschaft, Atmospheric Science

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/e29293c9-2909-4d2d-83ac-555654f62c31