Observation of sea-salt fraction in sub-100 nm diameter particles at Cape Grim

Cravigan, Luke T., Ristovski, Zoran, Modini, Robin L., Keywood, Melita D., & Gras, John L. (2015) Observation of sea-salt fraction in sub-100 nm diameter particles at Cape Grim. Journal of Geophysical Research: Atmospheres, 120(5), pp. 1848-1864.

View at publisher

Abstract

Volatility-hygroscopicity tandem differential mobility analyzer measurements were used to infer the composition of sub-100 nm diameter Southern Ocean marine aerosols at Cape Grim in November and December 2007. This study focuses on a short-lived high sea spray aerosol (SSA) event on 7–8 December with two externally mixed modes in the Hygroscopic Growth Factor (HGF) distributions (90% relative humidity (RH)), one at HGF > 2 and another at HGF~1.5. The particles with HGF > 2 displayed a deliquescent transition at 73–75% RH and were nonvolatile up to 280°C, which identified them as SSA particles with a large inorganic sea-salt fraction. SSA HGFs were 3–13% below those for pure sea-salt particles, indicating an organic volume fraction (OVF) of up to 11–46%. Observed high inorganic fractions in sub-100 nm SSA is contrary to similar, earlier studies. HGFs increased with decreasing particle diameter over the range 16–97 nm, suggesting a decreased OVF, again contrary to earlier studies. SSA comprised up to 69% of the sub-100 nm particle number, corresponding to concentrations of 110–290 cm−3. Air mass back trajectories indicate that SSA particles were produced 1500 km, 20–40 h upwind of Cape Grim. Transmission electron microscopy (TEM) and X-ray spectrometry measurements of sub-100 nm aerosols collected from the same location, and at the same time, displayed a distinct lack of sea salt. Results herein highlight the potential for biases in TEM analysis of the chemical composition of marine aerosols.

Impact and interest:

3 citations in Scopus
Search Google Scholar™
3 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

14 since deposited on 26 Apr 2016
14 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 95128
Item Type: Journal Article
Refereed: Yes
Additional URLs:
Keywords: marine aerosol, sea spray, CCN, hygroscopic growth, deliquescence, Cape Grim, entrainment
DOI: 10.1002/2014JD022601
ISSN: 2169-897X
Subjects: Australian and New Zealand Standard Research Classification > EARTH SCIENCES (040000) > ATMOSPHERIC SCIENCES (040100) > Atmospheric Aerosols (040101)
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2015 American Geophysical Union
Deposited On: 26 Apr 2016 01:21
Last Modified: 03 Dec 2016 22:27

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page