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| Titel |
Nitryl chloride as a ‘new’ radical source and its role in production of ozone in polluted troposphere: an overview of the results from four field campaigns in China |
| VerfasserIn |
Tao Wang, Yee Jun Tham, Likun Xue, Zhe Wang, Xinfeng Wang, Weihao Wang, Hao Wang, Hui Yun, Keding Lu, Min Shao, Peter K. K. Louie, Donald R. Blake, Steven S. Brown, Yuanhang Zhang |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250130786
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| Publikation (Nr.) |
 EGU/EGU2016-11094.pdf |
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| Zusammenfassung |
| Nitryl chloride (ClNO2) - a trace gas produced from heterogeneous reactions of dinitrogen
pentoxide (N2O5) on aerosols containing chorine - can significantly affect radical
budget and concentrations of ozone and other secondary pollutants. However, the
abundance, formation kinetics, and impact of ClNO2are not fully understood under
different environmental conditions. This presentation gives an overview of recent field
campaigns of ClNO2 and related chemical constituents in China, including one at a
mountain top (957 m a.s.l) in Hong Kong of South China in winter 2013 and three
in North China (urban Ji’nan, semi-rural Wangdu, and Mt Tai (1534 m a.s.l)) in
summer 2014. ClNO2 and N2O5 were measured with a chemical ionization mass
spectrometry (CIMS) system with iodide as the primary ions. Ambient concentrations of
several hundreds ppts and up to 4.7 ppbv of ClNO2were observed in these locations,
suggesting existence of elevated ClNO2 in both coastal and inland atmospheres of China.
Measurements in North China exhibited generally low concentrations of N2O5,
indicative of its fast uptake of on aerosols under aerosol and humid conditions.
Indications of anthropogenic sources of chloride were observed at all these sites.
The impact of photolysis of ClNO2 on radical budget and ozone enhancement was
assessed with a MCM model which was updated with detailed chlorine chemistry and
constrained by measurement data for the southern and a northern site. The results
show that the ClNO2 could increase ozone production by 2-16% in the following
day. Overall, our study re-affirms the need to include ClNO2 related reactions in
photochemical models for prediction of ground-level ozone in polluted environments. |
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