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

Journal metrics

Journal metrics

  • IF value: 5.509 IF 5.509
  • IF 5-year value: 5.689 IF 5-year 5.689
  • CiteScore value: 5.44 CiteScore 5.44
  • SNIP value: 1.519 SNIP 1.519
  • SJR value: 3.032 SJR 3.032
  • IPP value: 5.37 IPP 5.37
  • h5-index value: 86 h5-index 86
  • Scimago H index value: 161 Scimago H index 161
Discussion papers | Copyright
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 06 Aug 2018

Research article | 06 Aug 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).

Nitrate formation from heterogeneous uptake of dinitrogen pentoxide during a severe winter haze in southern China

Hui Yun1, Weihao Wang1, Tao Wang1, Men Xia1, Chuan Yu1,2, Zhe Wang1, Steven C. N. Poon1, Dingli Yue3, and Yan Zhou3 Hui Yun et al.
  • 1Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
  • 2Environment Research Institute, Shandong University, Jinan, China
  • 3Guangdong Environmental Monitoring Center, State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangzhou, China

Abstract. Nitrate (NO3) has become a major component of fine particulate matter (PM2.5) during hazy days in China. However, the role of the heterogeneous reactions of dinitrogen pentoxide (N2O5) in nitrate formation is not well constrained. In January 2017, a severe haze event occurred in the Pearl River Delta (PRD) of southern China during which high levels of PM2.5 (~400μgm−3) and O3 (~160ppbv) were observed at a semi-rural site (Heshan) in the western PRD. Nitrate concentrations were up to 108μgm−3 (1h time resolution), and the contribution of nitrate to PM2.5 reached nearly 40%. Concurrent increases in NO3 and ClNO2 (with a maximum value of 8.3ppbv in 1min time resolution) were observed in the first several hours after sunset, indicating an intense N2O5 heterogeneous uptake on aerosols. The formation potential of NO3 via N2O5 heterogeneous reactions was estimated to be 39.7 to 77.3μgm−3 in the early hours (3 to 6h) after sunset based on the measurement data, which could completely explain the measured increase in the NO3 concentration during the same time period. Daytime production of nitric acid from the gas-phase reaction of OH+NO2 was calculated with a chemical box model built using the Master Chemical Mechanism (MCM v3.3.1) and constrained by the measurement data. The integrated nocturnal nitrate formed via N2O5 chemistry was comparable to or even higher than the nitric acid formed during the daytime. This study confirms that N2O5 heterogeneous chemistry was a significant source of aerosol nitrate during hazy days in southern China.

Hui Yun 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/Co-Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Hui Yun et al.
Total article views: 433 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
318 110 5 433 18 5 13
  • HTML: 318
  • PDF: 110
  • XML: 5
  • Total: 433
  • Supplement: 18
  • BibTeX: 5
  • EndNote: 13
Views and downloads (calculated since 06 Aug 2018)
Cumulative views and downloads (calculated since 06 Aug 2018)
Viewed (geographical distribution)
Total article views: 433 (including HTML, PDF, and XML) Thereof 431 with geography defined and 2 with unknown origin.
Country # Views %
  • 1
No saved metrics found.
No discussed metrics found.
Latest update: 20 Oct 2018
Publications Copernicus
Special issue
Short summary
Based on the data analysis of simultaneous measurement of N2O5 and ClNO2 in a severe winter haze in the Pearl River Delta, this study underscores the importance of N2O5 heterogeneous reactions in nitrate formation and calls for better parameterization of N2O5 heterogeneous chemistry in order to predict haze pollution in China.
Based on the data analysis of simultaneous measurement of N2O5 and ClNO2 in a severe winter haze...