Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.414
IF5.414
IF 5-year value: 5.958
IF 5-year
5.958
CiteScore value: 9.7
CiteScore
9.7
SNIP value: 1.517
SNIP1.517
IPP value: 5.61
IPP5.61
SJR value: 2.601
SJR2.601
Scimago H <br class='widget-line-break'>index value: 191
Scimago H
index
191
h5-index value: 89
h5-index89
Preprints
https://doi.org/10.5194/acp-2020-457
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2020-457
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  14 May 2020

14 May 2020

Review status
This preprint is currently under review for the journal ACP.

Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation

Liqing Hao1, Eetu Kari1,a, Ari Leskinen1,2, Douglas R. Worsnop1,3, and Annele Virtanen1 Liqing Hao et al.
  • 1Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
  • 2Finnish Meteorological Institute, Kuopio, Finland
  • 3Aerodyne Research Inc., Billerica, MA 08121-3976, USA
  • anow at: Neste Oyj, Porvoo, Finland

Abstract. Ammonia (NH3), a gasous compound ubiquitiously present in the atmosphere, is involved in the formation of secondary organic aerosol (SOA), but the exact mechanisum is still not well known. This study presents the results of SOA experiments from the photooxidation of α-pinene in the presence of NH3 in the reaction chamber. SOA was formed in nucleation experiment and in seeded experiment with ammonium sulfate particles as seeds. The chemical composition and time-series of compounds in the gas- and particle- phase were characterized by an on-line high-resolution time-of-flight proton transfer reaction mass spectrometer (HR-ToF-PTRMS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), respectively. Our results show that for the aerosol particles in cloud condensation nuclei (CCN) size, the mass concentration of ammonium (NH4+) was still rising even after the mass concentration of organic component started to decrease due to aerosol wall deposition and evaporation, implying the continuous new formation of particle phase ammonium in the process. Stoichiometric neutralization analysis of aerosol indicates that organic acids have a central role in the formation of particle phase ammonium. Our measurements show a good correlation between the gas phase organic mono- and di-carboxylic acids formed in the photooxidation of α-pinene and the ammonium in the particle phase, thus highlighting the contribution of gas-phase organic acids to the ammonium formation in the CCN-size SOA particles. The work shows that the gas-phase organic acids contribute to the SOA formation by forming ammonium salts through acid-base reaction. The changes in aerosol mass, particle size and chemical composition resulting from the NH3-SOA interaction can potentially alter the aerosol direct and indirect forcing and therefore alter its impact on climate change.

Liqing Hao et al.

Interactive discussion

Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Liqing Hao et al.

Viewed

Total article views: 436 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
338 90 8 436 32 5 7
  • HTML: 338
  • PDF: 90
  • XML: 8
  • Total: 436
  • Supplement: 32
  • BibTeX: 5
  • EndNote: 7
Views and downloads (calculated since 14 May 2020)
Cumulative views and downloads (calculated since 14 May 2020)

Viewed (geographical distribution)

Total article views: 438 (including HTML, PDF, and XML) Thereof 438 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

No discussed metrics found.
Latest update: 24 Sep 2020
Publications Copernicus
Download
Short summary
Our work presents secondary organic aerosol (SOA) formation results in the presence of gaseous ammonia. The particle phase ammonium was continuously produced even after SOA formation has ceased. The gas phase organic acids were experimentally observed to contribute to the formed particle phase ammonium salts. This study suggests that the presence of ammonia may change the mass and chemical composition of large-size SOA particles and can potentially alter the aerosol impact on climate change.
Our work presents secondary organic aerosol (SOA) formation results in the presence of gaseous...
Citation
Altmetrics