Hygroscopicity and CCN potential of DMS-derived aerosol particles

Autor(en)

B. Rosati, S. Isokääntä, S. Christiansen, M. M. Jensen, S. P. Moosakutty, R. Wollesen de Jonge, A. Massling, M. Glasius, J. Elm, A. Virtanen, M. Bilde

Abstrakt

Dimethyl sulfide (DMS) is emitted by phytoplankton species in the oceans and constitutes the largest source of naturally emitted sulfur to the atmosphere. The climate impact of secondary particles, formed through the oxidation of DMS by hydroxyl radicals, is still elusive. This study investigates the hygroscopicity and cloud condensation nuclei activity of such particles and discusses the results in relation to their chemical composition. We show that mean hygroscopicity parameters, κ, during an experiment for particles of 80 nm in diameter range from 0.46 to 0.52 or higher, as measured at both sub- and supersaturated water vapour conditions. Ageing of the particles leads to an increase in κ from, for example, 0.50 to 0.58 over the course of 3 h (Exp. 7). Aerosol mass spectrometer measurements from this study indicate that this change most probably stems from a change in chemical composition leading to slightly higher fractions of ammonium sulfate compared to methanesulfonic acid (MSA) within the particles with ageing time. Lowering the temperature to 258 K increases κ slightly, particularly for small particles. These κ values are well comparable to previously reported model values for MSA or mixtures between MSA and ammonium sulfate. Particle nucleation and growth rates suggest a clear temperature dependence, with slower rates at cold temperatures. Quantum chemical calculations show that gas-phase MSA clusters are predominantly not hydrated, even at high humidity conditions, indicating that their gas-phase chemistry should be independent of relative humidity.

Organisation(en)

Aerosolphysik und Umweltphysik

Externe Organisation(en)

Aarhus University, University of Eastern Finland, University of the Faroe Islands, Stockholm University, Hamad Bin Khalifa University, Lund University

Journal

Atmospheric Chemistry and Physics

Band

22

Seiten

13449-13466

Anzahl der Seiten

18

ISSN

1680-7316

DOI

https://doi.org/10.5194/acp-22-13449-2022

Publikationsdatum

10-2022

Peer-reviewed

Ja

ÖFOS 2012

103037 Umweltphysik, 103039 Aerosolphysik, 105208 Atmosphärenchemie

Schlagwörter

ASJC Scopus Sachgebiete

Atmospheric Science

Sustainable Development Goals

SDG 13 – Maßnahmen zum Klimaschutz

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/1b9fd894-528e-4cf5-9d44-d7458538e16f