Hygroscopic properties of smoke-generated organic aerosol particles emitted in the marine atmosphere
Abstract
During the Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE), a plume of organic aerosol was produced by a smoke generator and emitted into the marine atmosphere from aboard the R/V Point Sur. In this study, the hygroscopic properties and the chemical composition of the plume were studied at plume ages between 0 and 4 h in different meteorological conditions. In sunny conditions, the plume particles had very low hygroscopic growth factors (GFs): between 1.05 and 1.09 for 30 nm and between 1.02 and 1.1 for 150 nm dry size at a relative humidity (RH) of 92%, contrasted by an average marine background GF of 1.6. New particles were produced in large quantities (several 10 000 cm^−3), which lead to substantially increased cloud condensation nuclei (CCN) concentrations at supersaturations between 0.07 and 0.88%. Ratios of oxygen to carbon (O : C) and water-soluble organic mass (WSOM) increased with plume age: from < 0.001 to 0.2, and from 2.42 to 4.96 μg m^−3, respectively, while organic mass fractions decreased slightly (~ 0.97 to ~ 0.94). High-resolution aerosol mass spectrometer (AMS) spectra show that the organic fragment m/z 43 was dominated by C_(2)H_(3)O^+ in the small, new particle mode and by C_(3)H_(7)^+ in the large particle mode. In the marine background aerosol, GFs for 150 nm particles at 40% RH were found to be enhanced at higher organic mass fractions: an average GF of 1.06 was observed for aerosols with an organic mass fraction of 0.53, and a GF of 1.04 for an organic mass fraction of 0.35.
Additional Information
© Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. Received: 15 April 2013; Published in Atmos. Chem. Phys. Discuss.: 6 May 2013; Revised: 12 August 2013; Accepted: 13 August 2013; Published: 7 October 2013. This work was funded by ONR grants N00014-11-1-0783, N00014-10-1-0200, and N00014-10-1-0811, and NSF grants AGS-1013381, AGS-10131423, and AGS-1008848. The measurements at sea were made possible by the support of the R/V Point Sur crew and staff. We acknowledge NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, for providing weather maps from their website at http://www.esrl.noaa.gov/psd/. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model and READY website (http://ready.arl.noaa.gov) used in this publication. Regina Hitzenberger is acknowledged for helpful comments and suggestions. Edited by: M. C. FacchiniAttached Files
Published - acp-13-9819-2013.pdf
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Additional details
- Eprint ID
- 42520
- Resolver ID
- CaltechAUTHORS:20131118-100634113
- N00014-11-1-0783
- Office of Naval Research (ONR)
- N00014-10-1-0200
- Office of Naval Research (ONR)
- N00014-10-1-0811
- Office of Naval Research (ONR)
- AGS-1013381
- NSF
- AGS-10131423
- NSF
- AGS-1008848
- NSF
- Created
-
2013-11-18Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field