Nitrate aerosol formation and source assessment in winter at different regions in Northeast China

Abstract. As one of the intense anthropogenic emission regions across the relatively high latitude (> 40° N) areas on the Earth, Northeast China faces serious problem on regional haze during long winter with half a year. Aerosols in polluted haze in Northeast China are poorly understood compared with the haze in other regions of China such as North China Plain. Here, we for the first time integrated bulk chemical measurements with single particle analysis from transmission electron microscopy (TEM), nanoscale secondary ion mass spectrometer (NanoSIMS), and atomic force microscopy (AFM) to obtain morphology, size, composition, aging process, and sources of aerosol particles collected during two contrasting regional haze events (Haze-I and Haze-II) at an urban site and a mountain site in Northeast China, and further investigated the causes of regional haze formation. Haze-I evolved from moderate (average PM2.5: 76–108 μg/m3) to heavy pollution (151–154 μg/m3), with the dominant PM2.5 component changing from organic matter (OM) (39–45 μg/m3) to secondary inorganic ions (94–101 μg/m3). Similarly, TEM observations showed that S-OM particles elevated from 29 % to 60 % by number at urban site and 64 % to 74 % at mountain site and 75–96 % of Haze-I particles included primary OM. Change of wind direction induced that Haze-I rapidly turned into Haze-II (185–223 μg/m3) with the predominant OM (98–133 μg/m3) and unexpectedly high K+ (3.8 μg/m3). TEM also showed that K-OM particles increased from 4–5 % by number to 50–52 %. Our study revealed a contrasting formation mechanism of these two haze events: Haze-I was induced by accumulation of primary OM emitted from residential coal burning and further deteriorated by secondary aerosol formation via heterogeneous reactions; Haze-II was caused by long-range transport of agricultural biomass burning emissions. Moreover, we found that 75–97 % of haze particles contained tarballs, but only 4–23 % contained black carbon and its concentrations were low at 2.7–4.3 μg/m3. The results highlight that abundant tarballs are important light-absorbing brown carbon in Northeast China during winter haze and further considered in climate models.

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Simulated Impacts of Sulfate and Nitrate Aerosol Formation on Surface-Layer Ozone Concentrations in China

Atmospheric and Oceanic Science Letters ◽

10.1080/16742834.2014.11447204 ◽

2014 ◽

Vol 7 (5) ◽

pp. 441-446 ◽

Cited By ~ 10

Author(s):

Yang Yang ◽

Liao Hong ◽

Lou Si-Jia

Keyword(s):

Surface Layer ◽

Aerosol Formation ◽

Ozone Concentrations ◽

Nitrate Aerosol

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Application of chemometrics to quantitative source assessment of crude oils from the Zhanhua Depression, Bohai Bay Basin, Northeast China

Journal of Asian Earth Sciences ◽

10.1016/j.jseaes.2021.104875 ◽

2021 ◽

pp. 104875

Author(s):

Xiao–Hui Lin ◽

Zhao–Wen Zhan ◽

Yan–Rong Zou ◽

Tian Liang ◽

Ping'an Peng

Keyword(s):

Northeast China ◽

Crude Oils ◽

Bohai Bay ◽

Bohai Bay Basin ◽

Source Assessment

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Nitrate aerosols today and in 2030: a global simulation including aerosols and tropospheric ozone

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-5043-2007 ◽

2007 ◽

Vol 7 (19) ◽

pp. 5043-5059 ◽

Cited By ~ 181

Author(s):

S. E. Bauer ◽

D. Koch ◽

N. Unger ◽

S. M. Metzger ◽

D. T. Shindell ◽

...

Keyword(s):

Climate Change ◽

Greenhouse Gas ◽

Radiative Forcing ◽

Air Pollutant ◽

Main Role ◽

Aerosol Formation ◽

Near Surface ◽

Sulphate Aerosols ◽

The Future ◽

Nitrate Aerosol

Abstract. Nitrate aerosols are expected to become more important in the future atmosphere due to the expected increase in nitrate precursor emissions and the decline of ammonium-sulphate aerosols in wide regions of this planet. The GISS climate model is used in this study, including atmospheric gas- and aerosol phase chemistry to investigate current and future (2030, following the SRES A1B emission scenario) atmospheric compositions. A set of sensitivity experiments was carried out to quantify the individual impact of emission- and physical climate change on nitrate aerosol formation. We found that future nitrate aerosol loads depend most strongly on changes that may occur in the ammonia sources. Furthermore, microphysical processes that lead to aerosol mixing play a very important role in sulphate and nitrate aerosol formation. The role of nitrate aerosols as climate change driver is analyzed and set in perspective to other aerosol and ozone forcings under pre-industrial, present day and future conditions. In the near future, year 2030, ammonium nitrate radiative forcing is about −0.14 W/m² and contributes roughly 10% of the net aerosol and ozone forcing. The present day nitrate and pre-industrial nitrate forcings are −0.11 and −0.05 W/m², respectively. The steady increase of nitrate aerosols since industrialization increases its role as a non greenhouse gas forcing agent. However, this impact is still small compared to greenhouse gas forcings, therefore the main role nitrate will play in the future atmosphere is as an air pollutant, with annual mean near surface air concentrations, in the fine particle mode, rising above 3 μg/m³ in China and therefore reaching pollution levels, like sulphate aerosols.

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Exploring the inorganic and organic nitrate aerosol formation regimes at a suburban site on the North China Plain

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.144538 ◽

2021 ◽

pp. 144538

Author(s):

Wei Huang ◽

Yuan Yang ◽

Yonghong Wang ◽

Wenkang Gao ◽

Haiyan Li ◽

...

Keyword(s):

North China Plain ◽

North China ◽

Organic Nitrate ◽

Aerosol Formation ◽

The North ◽

The North China Plain ◽

Suburban Site ◽

Nitrate Aerosol ◽

Inorganic And Organic

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Dramatic changes in Harbin aerosol during 2018–2020: the roles of open burning policy and secondary aerosol formation

10.5194/acp-2021-522 ◽

2021 ◽

Author(s):

Yuan Cheng ◽

Qin-qin Yu ◽

Jiu-meng Liu ◽

Xu-bing Cao ◽

Ying-jie Zhong ◽

...

Keyword(s):

Air Pollution ◽

Biomass Burning ◽

Northeast China ◽

Cold Climate ◽

Quality Data ◽

Aerosol Formation ◽

Secondary Aerosol ◽

Open Burning ◽

Measurement Period ◽

Related Increase

Abstract. Despite the growing interest in understanding haze formation in Chinese megacities, air pollution has been largely overlooked for the Harbin-Changchun (HC) metropolitan area located in the severe cold climate region in Northeast China. In this study, we unfolded significant variations of fine particulate matter (PM2.5) in HC’s central city (Harbin) during two sequential heating seasons of 2018–2019 and 2019–2020, and explored major drivers for the observed variations. The two campaigns showed comparable organic carbon (OC) levels but quite different OC sources. The biomass burning (BB) to OC contribution decreased substantially for 2019–2020, which was attributed primarily to the transition of local policies on agricultural fires, i.e., from the “legitimate burning” policy released in 2018 to the “strict prohibition” policy in 2019. Meanwhile, the contribution of secondary OC (OCsec) increased significantly, associated with the much more frequent occurrences of high relative humidity (RH) conditions during the 2019–2020 measurement period. Similar to OCsec, the major secondary inorganic ions, i.e., sulfate, nitrate and ammonium (SNA), also exhibited RH-dependent increases. Given the considerable aerosol water contents predicted for the high-RH conditions, heterogeneous reactions were likely at play in secondary aerosol formation even in the frigid atmosphere in Harbin (e.g., with daily average temperatures down to below −20 °C). In brief, compared to 2018–2019, the 2019–2020 measurement period was characterized by a policy-driven decrease of biomass burning OC, a RH-related increase of OCsec and a RH-related increase of SNA, with the former two factors generally offsetting each other. In addition, we found that open burning activities were actually not eliminated by the “strict prohibition” policy released in 2019, based on a synthesis of air quality data and fire count results. Although not evident throughout the 2019–2020 measurement period, agricultural fires broke out within a short period before crop planting in spring of 2020, and resulted in off-the-chart air pollution for Harbin, with 1- and 24-hour PM2.5 concentrations peaking at ~2350 and 900 μg/m3, respectively. This study indicates that sustainable use of crop residues remains a difficult challenge for the massive agricultural sector in Northeast China.

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Organic nitrate aerosol formation via NO<sub>3</sub> + BVOC in the Southeastern US

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-16235-2015 ◽

2015 ◽

Vol 15 (12) ◽

pp. 16235-16272 ◽

Cited By ~ 6

Author(s):

B. R. Ayres ◽

H. M. Allen ◽

D. C. Draper ◽

S. S. Brown ◽

R. J. Wild ◽

...

Keyword(s):

Mass Spectrometry ◽

Thermal Dissociation ◽

Organic Nitrate ◽

Organic Nitrates ◽

Ionization Mass ◽

Aerosol Formation ◽

Phase Measurements ◽

Aerosol Mass ◽

Southeastern Us ◽

Nitrate Aerosol

Abstract. Gas- and aerosol-phase measurements of oxidants, biogenic volatile organic compounds (BVOC) and organic nitrates made during the Southern Oxidant and Aerosol Study (SOAS campaign, Summer 2013) in central Alabama show that nitrate radical (NO3) reaction with monoterpenes leads to significant secondary aerosol formation. Cumulative losses of NO3 to terpenes are calculated and correlated to gas and aerosol organic nitrate concentrations made during the campaign. Correlation of NO3 radical consumption to organic nitrate aerosol as measured by Aerosol Mass Spectrometry (AMS) and Thermal Dissociation – Laser Induced Fluorescence (TD-LIF) suggests a range of molar yield of aerosol phase monoterpene nitrates of 23–44 %. Compounds observed via chemical ionization mass spectrometry (CIMS) are correlated to predicted nitrate loss to terpenes and show C10H17NO5, likely a hydroperoxy nitrate, is a major nitrate oxidized terpene product being incorporated into aerosols. The comparable isoprene product C5H9NO5 was observed to contribute less than 0.5 % of the total organic nitrate in the aerosol-phase and correlations show that it is principally a gas-phase product from nitrate oxidation of isoprene. Organic nitrates comprise between 30 and 45 % of the NOy budget during SOAS. Inorganic nitrates were also monitored and showed that during incidents of increased coarse-mode mineral dust, HNO3 uptake produced nitrate aerosol mass loading comparable to that of organic nitrate produced via NO3 + BVOC.

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Exploring wintertime regional haze in northeast China: role of coal and biomass burning

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-5355-2020 ◽

2020 ◽

Vol 20 (9) ◽

pp. 5355-5372 ◽

Cited By ~ 4

Author(s):

Jian Zhang ◽

Lei Liu ◽

Liang Xu ◽

Qiuhan Lin ◽

Hujia Zhao ◽

...

Keyword(s):

Biomass Burning ◽

Northeast China ◽

Aerosol Particles ◽

Urban Site ◽

Particle Analysis ◽

Aerosol Formation ◽

Tar Balls ◽

Mountain Site ◽

Regional Haze ◽

Haze Formation

Abstract. As one of the intense anthropogenic emission regions across the relatively high-latitude (>40∘ N) areas on Earth, northeast China faces the serious problem of regional haze during the heating period of the year. Aerosols in polluted haze in northeast China are poorly understood compared with the haze in other regions of China such as the North China Plain. Here, we integrated bulk chemical measurements with single-particle analysis from transmission electron microscopy (TEM), nanoscale secondary ion mass spectrometry (NanoSIMS), and atomic force microscopy (AFM) to obtain morphology, size, composition, aging process, and sources of aerosol particles collected during two contrasting regional haze events (Haze-I and Haze-II) at an urban site and a mountain site in northeast China and further investigated the causes of regional haze formation. Haze-I evolved from moderate (average PM2.5: 76–108 µg m−3) to heavy pollution (151–154 µg m−3), with the dominant PM2.5 component changing from organic matter (OM) (39–45 µg m−3) to secondary inorganic ions (94–101 µg m−3). Similarly, TEM observations showed that S-rich particles internally mixed with OM (named S-OM) increased from 29 % to 60 % by number at an urban site and 64 % to 74 % at a mountain site from the moderate Haze-I to heavy Haze-I events, and 75 %–96 % of Haze-I particles included primary OM. We found that change of wind direction caused Haze-I to rapidly turn into Haze-II (185–223 µg m−3) with predominantly OM (98–133 µg m−3) and unexpectedly high K+ (3.8 µg m−3). TEM also showed that K-rich particles internally mixed with OM (named K-OM) increased from 4 %–5 % by number to 50 %–52 %. The results indicate that there were different sources of aerosol particles causing the Haze-I and Haze-II formation: Haze-I was mainly induced by accumulation of primary OM emitted from residential coal burning and further deteriorated by secondary aerosol formation via heterogeneous reactions; Haze-II was caused by long-range transport of agricultural biomass burning emissions. Moreover, abundant primary OM particles emitted from coal and biomass burning were considered to be one typical brown carbon, i.e., tar balls. Our study highlights that large numbers of light-absorbing tar balls significantly contribute to winter haze formation in northeast China and they should be further considered in climate models.

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