Nitrate-driven urban haze pollution during summertime over the North China Plain
Compared to the severe winter haze episodes in the North China Plain (NCP), haze pollution during summertime has drawn little public attention. In this study, we present the highly time-resolved chemical composition of submicron particles (PM<sub>1</sub>) measured in Beijing and Xinxi...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2018-04-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/18/5293/2018/acp-18-5293-2018.pdf |
| _version_ | 1819267033853853696 |
|---|---|
| author | H. Li Q. Zhang B. Zheng C. Chen N. Wu H. Guo Y. Zhang Y. Zheng X. Li K. He K. He |
| author_facet | H. Li Q. Zhang B. Zheng C. Chen N. Wu H. Guo Y. Zhang Y. Zheng X. Li K. He K. He |
| author_sort | H. Li |
| collection | DOAJ |
| description | Compared to the severe winter haze episodes in the North China Plain (NCP),
haze pollution during summertime has drawn little public attention. In this
study, we present the highly time-resolved chemical composition of submicron
particles (PM<sub>1</sub>) measured in Beijing and Xinxiang in the NCP region
during summertime to evaluate the driving factors of aerosol pollution.
During the campaign periods (30 June to 27 July 2015, for Beijing and 8 to
25 June 2017, for Xinxiang), the average PM<sub>1</sub> concentrations were 35.0
and 64.2 µg m<sup>−3</sup> in Beijing and Xinxiang. Pollution episodes
characterized with largely enhanced nitrate concentrations were observed at
both sites. In contrast to the slightly decreased mass fractions of sulfate,
semivolatile oxygenated organic aerosol (SV-OOA), and low-volatility
oxygenated organic aerosol (LV-OOA) in PM<sub>1</sub>, nitrate displayed a
significantly enhanced contribution with the aggravation of aerosol
pollution, highlighting the importance of nitrate formation as the driving
force of haze evolution in summer. Rapid nitrate production mainly occurred
after midnight, with a higher formation rate than that of sulfate, SV-OOA, or
LV-OOA. Based on observation measurements and thermodynamic modeling, high
ammonia emissions in the NCP region favored the high nitrate production in
summer. Nighttime nitrate formation through heterogeneous hydrolysis of
dinitrogen pentoxide (N<sub>2</sub>O<sub>5</sub>) enhanced with the development of haze
pollution. In addition, air masses from surrounding polluted areas during
haze episodes led to more nitrate production. Finally, atmospheric
particulate nitrate data acquired by mass spectrometric techniques from
various field campaigns in Asia, Europe, and North America uncovered a higher
concentration and higher fraction of nitrate present in China. Although
measurements in Beijing during different years demonstrate a decline in the
nitrate concentration in recent years, the nitrate contribution in PM<sub>1</sub>
still remains high. To effectively alleviate particulate matter pollution in
summer, our results suggest an urgent need to initiate ammonia emission
control measures and further reduce nitrogen oxide emissions over the NCP
region. |
| first_indexed | 2024-12-23T21:10:44Z |
| format | Article |
| id | doaj.art-1e6d780ccc114d078358e873c32bd761 |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-12-23T21:10:44Z |
| publishDate | 2018-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-1e6d780ccc114d078358e873c32bd7612022-12-21T17:31:05ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242018-04-01185293530610.5194/acp-18-5293-2018Nitrate-driven urban haze pollution during summertime over the North China PlainH. Li0Q. Zhang1B. Zheng2C. Chen3N. Wu4H. Guo5Y. Zhang6Y. Zheng7X. Li8K. He9K. He10State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, ChinaMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaLaboratoire des Sciences du Climat et de l'Environnement, CEA-CNRS-UVSQ, UMR8212, Gif-sur-Yvette, FranceMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaSchool of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USAMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaMinistry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, ChinaState Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, ChinaState Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Tsinghua University, Beijing 100084, ChinaCompared to the severe winter haze episodes in the North China Plain (NCP), haze pollution during summertime has drawn little public attention. In this study, we present the highly time-resolved chemical composition of submicron particles (PM<sub>1</sub>) measured in Beijing and Xinxiang in the NCP region during summertime to evaluate the driving factors of aerosol pollution. During the campaign periods (30 June to 27 July 2015, for Beijing and 8 to 25 June 2017, for Xinxiang), the average PM<sub>1</sub> concentrations were 35.0 and 64.2 µg m<sup>−3</sup> in Beijing and Xinxiang. Pollution episodes characterized with largely enhanced nitrate concentrations were observed at both sites. In contrast to the slightly decreased mass fractions of sulfate, semivolatile oxygenated organic aerosol (SV-OOA), and low-volatility oxygenated organic aerosol (LV-OOA) in PM<sub>1</sub>, nitrate displayed a significantly enhanced contribution with the aggravation of aerosol pollution, highlighting the importance of nitrate formation as the driving force of haze evolution in summer. Rapid nitrate production mainly occurred after midnight, with a higher formation rate than that of sulfate, SV-OOA, or LV-OOA. Based on observation measurements and thermodynamic modeling, high ammonia emissions in the NCP region favored the high nitrate production in summer. Nighttime nitrate formation through heterogeneous hydrolysis of dinitrogen pentoxide (N<sub>2</sub>O<sub>5</sub>) enhanced with the development of haze pollution. In addition, air masses from surrounding polluted areas during haze episodes led to more nitrate production. Finally, atmospheric particulate nitrate data acquired by mass spectrometric techniques from various field campaigns in Asia, Europe, and North America uncovered a higher concentration and higher fraction of nitrate present in China. Although measurements in Beijing during different years demonstrate a decline in the nitrate concentration in recent years, the nitrate contribution in PM<sub>1</sub> still remains high. To effectively alleviate particulate matter pollution in summer, our results suggest an urgent need to initiate ammonia emission control measures and further reduce nitrogen oxide emissions over the NCP region.https://www.atmos-chem-phys.net/18/5293/2018/acp-18-5293-2018.pdf |
| spellingShingle | H. Li Q. Zhang B. Zheng C. Chen N. Wu H. Guo Y. Zhang Y. Zheng X. Li K. He K. He Nitrate-driven urban haze pollution during summertime over the North China Plain Atmospheric Chemistry and Physics |
| title | Nitrate-driven urban haze pollution during summertime over the North China Plain |
| title_full | Nitrate-driven urban haze pollution during summertime over the North China Plain |
| title_fullStr | Nitrate-driven urban haze pollution during summertime over the North China Plain |
| title_full_unstemmed | Nitrate-driven urban haze pollution during summertime over the North China Plain |
| title_short | Nitrate-driven urban haze pollution during summertime over the North China Plain |
| title_sort | nitrate driven urban haze pollution during summertime over the north china plain |
| url | https://www.atmos-chem-phys.net/18/5293/2018/acp-18-5293-2018.pdf |
| work_keys_str_mv | AT hli nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT qzhang nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT bzheng nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT cchen nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT nwu nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT hguo nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT yzhang nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT yzheng nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT xli nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT khe nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain AT khe nitratedrivenurbanhazepollutionduringsummertimeoverthenorthchinaplain |