Articles | Volume 23, issue 21
https://doi.org/10.5194/acp-23-13597-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-23-13597-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Nov 2023
Research article |
| 01 Nov 2023
| 01 Nov 2023
Mixing state and effective density of aerosol particles during the Beijing 2022 Olympic Winter Games
Aodong Du
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Jiaxing Sun
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
Weiqi Xu
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
Yuting Zhang
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, China
Xubing Du
Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, China
Guangdong Provincial Engineering Research Center for On-Line Source Apportionment System of Air Pollution, Guangzhou 510632, China
Yan Li
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Xiaole Pan
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
Zifa Wang
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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Junhua Wang, Baozhu Ge, Xueshun Chen, Jie Li, Keding Lu, Yayuan Dong, Lei Kong, Zifa Wang, and Yuanhang Zhang
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Revised manuscript not accepted
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Shixian Zhai, Daniel J. Jacob, Drew C. Pendergrass, Nadia K. Colombi, Viral Shah, Laura Hyesung Yang, Qiang Zhang, Shuxiao Wang, Hwajin Kim, Yele Sun, Jin-Soo Choi, Jin-Soo Park, Gan Luo, Fangqun Yu, Jung-Hun Woo, Younha Kim, Jack E. Dibb, Taehyoung Lee, Jin-Seok Han, Bruce E. Anderson, Ke Li, and Hong Liao
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Shujun Zhong, Shuang Chen, Junjun Deng, Yanbing Fan, Qiang Zhang, Qiaorong Xie, Yulin Qi, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Jialei Zhu, Xin Wang, Di Liu, Xiaole Pan, Yele Sun, Zifa Wang, Yisheng Xu, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 23, 2061–2077, https://doi.org/10.5194/acp-23-2061-2023, https://doi.org/10.5194/acp-23-2061-2023, 2023
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This study investigated the role of the secondary organic aerosol (SOA) loading on the molecular composition of wintertime urban aerosols by ultrahigh-resolution mass spectrometry. Results demonstrate that the SOA loading is an important factor associated with the oxidation degree, nitrate group content, and chemodiversity of nitrooxy–organosulfates. Our study also found that the hydrolysis of nitrooxy–organosulfates is a possible pathway for the formation of organosulfates.
Yuying Wang, Rong Hu, Qiuyan Wang, Zhanqing Li, Maureen Cribb, Yele Sun, Xiaorui Song, Yi Shang, Yixuan Wu, Xin Huang, and Yuxiang Wang
Atmos. Chem. Phys., 22, 14133–14146, https://doi.org/10.5194/acp-22-14133-2022, https://doi.org/10.5194/acp-22-14133-2022, 2022
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The mixing state of size-resolved soot particles and their influencing factors were investigated. The results suggest anthropogenic emissions and aging processes have diverse impacts on the mixing state of soot particles in different modes. Considering that the mixing state of soot particles is crucial to model aerosol absorption, this finding is important to study particle growth and the warming effect of black carbon aerosols.
Futing Wang, Ting Yang, Zifa Wang, Haibo Wang, Xi Chen, Yele Sun, Jianjun Li, Guigang Tang, and Wenxuan Chai
Atmos. Meas. Tech., 15, 6127–6144, https://doi.org/10.5194/amt-15-6127-2022, https://doi.org/10.5194/amt-15-6127-2022, 2022
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We develop a new algorithm to get the vertical mass concentration profiles of fine aerosol components based on the synergy of ground-based remote sensing for the first time. The comparisons with in situ observations and chemistry transport models validate the performance of the algorithm. Uncertainties caused by input parameters are also assessed in this paper. We expected that the algorithm can provide a new idea for lidar inversion and promote the development of aerosol component profiles.
Chao Yan, Yicheng Shen, Dominik Stolzenburg, Lubna Dada, Ximeng Qi, Simo Hakala, Anu-Maija Sundström, Yishuo Guo, Antti Lipponen, Tom V. Kokkonen, Jenni Kontkanen, Runlong Cai, Jing Cai, Tommy Chan, Liangduo Chen, Biwu Chu, Chenjuan Deng, Wei Du, Xiaolong Fan, Xu-Cheng He, Juha Kangasluoma, Joni Kujansuu, Mona Kurppa, Chang Li, Yiran Li, Zhuohui Lin, Yiliang Liu, Yuliang Liu, Yiqun Lu, Wei Nie, Jouni Pulliainen, Xiaohui Qiao, Yonghong Wang, Yifan Wen, Ye Wu, Gan Yang, Lei Yao, Rujing Yin, Gen Zhang, Shaojun Zhang, Feixue Zheng, Ying Zhou, Antti Arola, Johanna Tamminen, Pauli Paasonen, Yele Sun, Lin Wang, Neil M. Donahue, Yongchun Liu, Federico Bianchi, Kaspar R. Daellenbach, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Aijun Ding, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 22, 12207–12220, https://doi.org/10.5194/acp-22-12207-2022, https://doi.org/10.5194/acp-22-12207-2022, 2022
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Atmospheric new particle formation (NPF) is a dominant source of atmospheric ultrafine particles. In urban environments, traffic emissions are a major source of primary pollutants, but their contribution to NPF remains under debate. During the COVID-19 lockdown, traffic emissions were significantly reduced, providing a unique chance to examine their relevance to NPF. Based on our comprehensive measurements, we demonstrate that traffic emissions alone are not able to explain the NPF in Beijing.
Mengying Li, Shaocai Yu, Xue Chen, Zhen Li, Yibo Zhang, Zhe Song, Weiping Liu, Pengfei Li, Xiaoye Zhang, Meigen Zhang, Yele Sun, Zirui Liu, Caiping Sun, Jingkun Jiang, Shuxiao Wang, Benjamin N. Murphy, Kiran Alapaty, Rohit Mathur, Daniel Rosenfeld, and John H. Seinfeld
Atmos. Chem. Phys., 22, 11845–11866, https://doi.org/10.5194/acp-22-11845-2022, https://doi.org/10.5194/acp-22-11845-2022, 2022
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This study constructed an emission inventory of condensable particulate matter (CPM) in China with a focus on organic aerosols (OAs), based on collected CPM emission information. The results show that OA emissions are enhanced twofold for the years 2014 and 2017 after the inclusion of CPM in the new inventory. Sensitivity cases demonstrated the significant contributions of CPM emissions from stationary combustion and mobile sources to primary, secondary, and total OA concentrations.
Lichao Yang, Wansuo Duan, Zifa Wang, and Wenyi Yang
Atmos. Chem. Phys., 22, 11429–11453, https://doi.org/10.5194/acp-22-11429-2022, https://doi.org/10.5194/acp-22-11429-2022, 2022
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The initial meteorological state has a great impact on PM2.5 forecasts. Assimilating additional observations is an effective way to improve the accuracy of the initial meteorological state. Here we used an advanced optimization approach to identify where we should preferentially place the meteorological observations associated with PM2.5 forecasts in the Beijing–Tianjin–Hebei region of China. We provide evidence that the target observation strategy is effective for improving PM2.5 forecasts.
Zhiqiang Zhang, Yele Sun, Chun Chen, Bo You, Aodong Du, Weiqi Xu, Yan Li, Zhijie Li, Lu Lei, Wei Zhou, Jiaxing Sun, Yanmei Qiu, Lianfang Wei, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 22, 10409–10423, https://doi.org/10.5194/acp-22-10409-2022, https://doi.org/10.5194/acp-22-10409-2022, 2022
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We present a comprehensive characterization of water-soluble organic aerosol and the first mass spectral characterization of water-insoluble organic aerosol in the cold season in Beijing by integrating online and offline aerosol mass spectrometer measurements. WSOA comprised dominantly secondary OA and showed large changes during the transition season from autumn to winter. WIOA was characterized by prominent hydrocarbon ions series, low oxidation states, and significant day–night differences.
Guohua Zhang, Xiaodong Hu, Wei Sun, Yuxiang Yang, Ziyong Guo, Yuzhen Fu, Haichao Wang, Shengzhen Zhou, Lei Li, Mingjin Tang, Zongbo Shi, Duohong Chen, Xinhui Bi, and Xinming Wang
Atmos. Chem. Phys., 22, 9571–9582, https://doi.org/10.5194/acp-22-9571-2022, https://doi.org/10.5194/acp-22-9571-2022, 2022
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We show a significant enhancement of nitrate mass fraction in cloud water and relative intensity of nitrate in the cloud residual particles and highlight that hydrolysis of N2O5 serves as the critical route for the in-cloud formation of nitrate, even during the daytime. Given that N2O5 hydrolysis acts as a major sink of NOx in the atmosphere, further model updates may improve our understanding about the processes contributing to nitrate production in cloud and the cycling of odd nitrogen.
Xuan Li, Lei Li, Zeming Zhuo, Guohua Zhang, Xubing Du, Xue Li, Zhengxu Huang, Zhen Zhou, and Zhi Cheng
EGUsphere, https://doi.org/10.5194/egusphere-2022-598, https://doi.org/10.5194/egusphere-2022-598, 2022
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The particle size and chemical composition of bioaerosol were analyzed based on single particle aerosol mass spectrometer. Fungal aerosol of 10 μm was measured for the first time and the characteristic spectrum of bioaerosol was updated. The ion peak ratio method can distinguish bioaerosols from interferers by 97 %. The factors influencing the differentiation of bioaerosols are also discussed. Single particle mass spectrometry can be a new method for real-time identification of bioaerosols.
Jiaxing Sun, Yele Sun, Conghui Xie, Weiqi Xu, Chun Chen, Zhe Wang, Lei Li, Xubing Du, Fugui Huang, Yan Li, Zhijie Li, Xiaole Pan, Nan Ma, Wanyun Xu, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 22, 7619–7630, https://doi.org/10.5194/acp-22-7619-2022, https://doi.org/10.5194/acp-22-7619-2022, 2022
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We analyzed the chemical composition and mixing state of BC-containing particles at urban and rural sites in winter in the North China Plain and evaluated their impact on light absorption enhancement. BC was dominantly mixed with organic carbon, nitrate, and sulfate, and the mixing state evolved significantly as a function of relative humidity (RH) at both sites. The absorption enhancement depended strongly on coated secondary inorganic aerosol and was up to ~1.3–1.4 during aging processes.
Junjun Deng, Hao Ma, Xinfeng Wang, Shujun Zhong, Zhimin Zhang, Jialei Zhu, Yanbing Fan, Wei Hu, Libin Wu, Xiaodong Li, Lujie Ren, Chandra Mouli Pavuluri, Xiaole Pan, Yele Sun, Zifa Wang, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 22, 6449–6470, https://doi.org/10.5194/acp-22-6449-2022, https://doi.org/10.5194/acp-22-6449-2022, 2022
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Light-absorbing brown carbon (BrC) plays an important role in climate change and atmospheric chemistry. Here we investigated the seasonal and diurnal variations in water-soluble BrC in PM2.5 in the megacity Tianjin in coastal China. Results of the source apportionments from the combination with organic molecular compositions and optical properties of water-soluble BrC reveal a large contribution from primary bioaerosol particles to BrC in the urban atmosphere.
Haibo Wang, Ting Yang, Zifa Wang, Jianjun Li, Wenxuan Chai, Guigang Tang, Lei Kong, and Xueshun Chen
Geosci. Model Dev., 15, 3555–3585, https://doi.org/10.5194/gmd-15-3555-2022, https://doi.org/10.5194/gmd-15-3555-2022, 2022
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In this paper, we develop an online data coupled assimilation system (NAQPMS-PDAF) with the Eulerian atmospheric chemistry-transport model. NAQPMS-PDAF allows efficient use of large computational resources. The application and performance of the system are investigated by assimilating 1 month of vertical aerosol observations. The results show that NAQPMS-PDAF can significantly improve the performance of aerosol vertical structure simulation and reduce the uncertainty to a large extent.
Jingnan Shi, Juan Hong, Nan Ma, Qingwei Luo, Yao He, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Shuang Han, Long Peng, Linhong Xie, Guangsheng Zhou, Wanyun Xu, Yele Sun, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 4599–4613, https://doi.org/10.5194/acp-22-4599-2022, https://doi.org/10.5194/acp-22-4599-2022, 2022
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In this study, we investigated the hygroscopicity of submicron aerosols at a rural site in the North China Plain during the winter of 2018, using a HTDMA and a CV-ToF-ACSM. We observed differences in aerosol hygroscopicity during two distinct episodes with different primary emissions and secondary aerosol formation processes. These results provide an improved understanding of the complex influence of sources and aerosol evolution processes on their hygroscopicity.
Jing Cai, Cheng Wu, Jiandong Wang, Wei Du, Feixue Zheng, Simo Hakala, Xiaolong Fan, Biwu Chu, Lei Yao, Zemin Feng, Yongchun Liu, Yele Sun, Jun Zheng, Chao Yan, Federico Bianchi, Markku Kulmala, Claudia Mohr, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 22, 1251–1269, https://doi.org/10.5194/acp-22-1251-2022, https://doi.org/10.5194/acp-22-1251-2022, 2022
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This study investigates the connection between organic aerosol (OA) molecular composition and particle absorptive properties in autumn in Beijing. We find that the molecular properties of OA compounds in different episodes influence particle light absorption properties differently: the light absorption enhancement of black carbon and light absorption coefficient of brown carbon were mostly related to more oxygenated OA (low C number and four O atoms) and aromatics/nitro-aromatics, respectively.
Jiaxing Sun, Zhe Wang, Wei Zhou, Conghui Xie, Cheng Wu, Chun Chen, Tingting Han, Qingqing Wang, Zhijie Li, Jie Li, Pingqing Fu, Zifa Wang, and Yele Sun
Atmos. Chem. Phys., 22, 561–575, https://doi.org/10.5194/acp-22-561-2022, https://doi.org/10.5194/acp-22-561-2022, 2022
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We analyzed 9-year measurements of BC and aerosol optical properties from 2012 to 2020 in Beijing, China. Our results showed large reductions in BC and light extinction coefficient due to the Clean Air Action Plan. As a response, both SSA and mass extinction efficiency (MEE) showed considerable increases, demonstrating a future challenge in visibility improvement. The primary and secondary BrC was also separated and quantified, and the changes in radiative forcing of BC and BrC were estimated.
Qian Ye, Jie Li, Xueshun Chen, Huansheng Chen, Wenyi Yang, Huiyun Du, Xiaole Pan, Xiao Tang, Wei Wang, Lili Zhu, Jianjun Li, Zhe Wang, and Zifa Wang
Geosci. Model Dev., 14, 7573–7604, https://doi.org/10.5194/gmd-14-7573-2021, https://doi.org/10.5194/gmd-14-7573-2021, 2021
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We developed a global tropospheric atmospheric chemistry source–receptor model. This model can quantify the contributions of multiple air pollutants from various source regions in one simulation without introducing the nonlinear error of atmospheric chemistry. The S-R relationships of PM2.5 and O3 from a global high-resolution (0.5° × 0.5°) simulation were given and compared with previous studies. This model will be useful for creating a link between the scientific community and policymakers.
Qi En Zhong, Chunlei Cheng, Zaihua Wang, Lei Li, Mei Li, Dafeng Ge, Lei Wang, Yuanyuan Li, Wei Nie, Xuguang Chi, Aijun Ding, Suxia Yang, Duohong Chen, and Zhen Zhou
Atmos. Chem. Phys., 21, 17953–17967, https://doi.org/10.5194/acp-21-17953-2021, https://doi.org/10.5194/acp-21-17953-2021, 2021
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Particulate amines play important roles in new particle formation, aerosol acidity, and hygroscopicity. Most of the field observations did not distinguish the different behavior of each type amine under the same ambient influencing factors. In this study, two amine-containing single particles exhibited different mixing states and disparate enrichment of secondary organics, which provide insight into the discriminated fates of organics during the formation and evolution processes.
Yuting Zhang, Hang Liu, Shandong Lei, Wanyun Xu, Yu Tian, Weijie Yao, Xiaoyong Liu, Qi Liao, Jie Li, Chun Chen, Yele Sun, Pingqing Fu, Jinyuan Xin, Junji Cao, Xiaole Pan, and Zifa Wang
Atmos. Chem. Phys., 21, 17631–17648, https://doi.org/10.5194/acp-21-17631-2021, https://doi.org/10.5194/acp-21-17631-2021, 2021
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In this study, the authors used a single-particle soot photometer (SP2) to characterize the particle size, mixing state, and optical properties of black carbon aerosols in rural areas of the North China Plain in winter. Relatively warm and high-RH environments (RH > 50 %, −4° < T < 4 °) were more favorable to rBC aging than dry and cold environments (RH < 60 %, T < −8°). The paper emphasizes the importance of meteorological parameters in the mixing state of black carbon.
Sihui Jiang, Fang Zhang, Jingye Ren, Lu Chen, Xing Yan, Jieyao Liu, Yele Sun, and Zhanqing Li
Atmos. Chem. Phys., 21, 14293–14308, https://doi.org/10.5194/acp-21-14293-2021, https://doi.org/10.5194/acp-21-14293-2021, 2021
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New particle formation (NPF) can be a large source of CCN and affect weather and climate. Here we show that the NPF contributes largely to cloud droplet number concentration (Nd) but is suppressed at high particle number concentrations in Beijing due to water vapor competition. We also reveal a considerable impact of primary sources on the evaluation in the urban atmosphere. Our study has great significance for assessing NPF-associated effects on climate in polluted regions.
Hong Ren, Wei Hu, Lianfang Wei, Siyao Yue, Jian Zhao, Linjie Li, Libin Wu, Wanyu Zhao, Lujie Ren, Mingjie Kang, Qiaorong Xie, Sihui Su, Xiaole Pan, Zifa Wang, Yele Sun, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 21, 12949–12963, https://doi.org/10.5194/acp-21-12949-2021, https://doi.org/10.5194/acp-21-12949-2021, 2021
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This study presents vertical profiles of biogenic and anthropogenic secondary organic aerosols (SOAs) in the urban boundary layer based on a 325 m tower in Beijing in late summer. The increases in the isoprene and toluene SOAs with height were found to be more related to regional transport, whereas the decrease in those from monoterpenes and sesquiterpene were more subject to local emissions. Such complicated vertical distributions of SOA should be considered in future modeling work.
Junhua Wang, Baozhu Ge, Xueshun Chen, Jie Li, Keding Lu, Yayuan Dong, Lei Kong, Zifa Wang, and Yuanhang Zhang
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-259, https://doi.org/10.5194/gmd-2021-259, 2021
Revised manuscript not accepted
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This paper developed a novel quantitative decoupling analysis (QDA) method to quantify the contributions of emission, meteorology, chemical reaction, and their nonlinear interactions on PM2.5 and applied it to a pollution episode in Beijing. This method can provides the researchers and policy makers with valuable information for understanding of key factors to heavy pollution, but also help the modelers to find out the sources of uncertainties among numerical models.
Yang Yang, Minqiang Zhou, Ting Wang, Bo Yao, Pengfei Han, Denghui Ji, Wei Zhou, Yele Sun, Gengchen Wang, and Pucai Wang
Atmos. Chem. Phys., 21, 11741–11757, https://doi.org/10.5194/acp-21-11741-2021, https://doi.org/10.5194/acp-21-11741-2021, 2021
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This study introduces the in situ CO2 measurement system installed in Beijing (urban), Xianghe (suburban), and Xinglong (rural) in North China for the first time. The spatial and temporal variations in CO2 mole fractions at the three sites between June 2018 and April 2020 are discussed on both seasonal and diurnal scales.
Qiaorong Xie, Sihui Su, Jing Chen, Yuqing Dai, Siyao Yue, Hang Su, Haijie Tong, Wanyu Zhao, Lujie Ren, Yisheng Xu, Dong Cao, Ying Li, Yele Sun, Zifa Wang, Cong-Qiang Liu, Kimitaka Kawamura, Guibin Jiang, Yafang Cheng, and Pingqing Fu
Atmos. Chem. Phys., 21, 11453–11465, https://doi.org/10.5194/acp-21-11453-2021, https://doi.org/10.5194/acp-21-11453-2021, 2021
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This study investigated the role of nighttime chemistry during Chinese New Year's Eve that enhances the formation of nitrooxy organosulfates in the aerosol phase. Results show that anthropogenic precursors, together with biogenic ones, considerably contribute to the formation of low-volatility nitrooxy OSs. Our study provides detailed molecular composition of firework-related aerosols, which gives new insights into the physicochemical properties and potential health effects of urban aerosols.
Ying Wei, Xueshun Chen, Huansheng Chen, Yele Sun, Wenyi Yang, Huiyun Du, Qizhong Wu, Dan Chen, Xiujuan Zhao, Jie Li, and Zifa Wang
Geosci. Model Dev., 14, 4411–4428, https://doi.org/10.5194/gmd-14-4411-2021, https://doi.org/10.5194/gmd-14-4411-2021, 2021
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The sub-grid particle formation (SGPF) in plumes plays an important role in air pollution and climate. We coupled an SGPF scheme to a chemical transport model with an aerosol microphysics module and applied it to investigate the SGPF impact over China. The scheme clearly improved the model performance in simulating aerosol components and particle number at typical sites influenced by point sources. The results indicate the significant effects of SGPF on aerosol particles in industrial areas.
Baozhu Ge, Danhui Xu, Oliver Wild, Xuefeng Yao, Junhua Wang, Xueshun Chen, Qixin Tan, Xiaole Pan, and Zifa Wang
Atmos. Chem. Phys., 21, 9441–9454, https://doi.org/10.5194/acp-21-9441-2021, https://doi.org/10.5194/acp-21-9441-2021, 2021
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In this study, an improved sequential sampling method is developed and implemented to estimate the contribution of below-cloud and in-cloud wet deposition over four years of measurements in Beijing. We find that the contribution of below-cloud scavenging for Ca2+, SO4 2–, and NH4+ decreases from above 50 % in 2014 to below 40 % in 2017. This suggests that the Action Plan has mitigated particulate matter pollution in the surface layer and hence decreased scavenging due to the washout process.
Xueshun Chen, Fangqun Yu, Wenyi Yang, Yele Sun, Huansheng Chen, Wei Du, Jian Zhao, Ying Wei, Lianfang Wei, Huiyun Du, Zhe Wang, Qizhong Wu, Jie Li, Junling An, and Zifa Wang
Atmos. Chem. Phys., 21, 9343–9366, https://doi.org/10.5194/acp-21-9343-2021, https://doi.org/10.5194/acp-21-9343-2021, 2021
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Atmospheric aerosol particles have significant climate and health effects that depend on aerosol size, composition, and mixing state. A new global-regional nested aerosol model with an advanced particle microphysics module and a volatility basis set organic aerosol module was developed to simulate aerosol microphysical processes. Simulations strongly suggest the important role of anthropogenic organic species in particle formation over the areas influenced by anthropogenic sources.
Syuichi Itahashi, Baozhu Ge, Keiichi Sato, Zhe Wang, Junichi Kurokawa, Jiani Tan, Kan Huang, Joshua S. Fu, Xuemei Wang, Kazuyo Yamaji, Tatsuya Nagashima, Jie Li, Mizuo Kajino, Gregory R. Carmichael, and Zifa Wang
Atmos. Chem. Phys., 21, 8709–8734, https://doi.org/10.5194/acp-21-8709-2021, https://doi.org/10.5194/acp-21-8709-2021, 2021
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This study presents the detailed analysis of acid deposition over southeast Asia based on the Model Inter-Comparison Study for Asia (MICS-Asia) phase III. Simulated wet deposition is evaluated with observation data from the Acid Deposition Monitoring Network in East Asia (EANET). The difficulties of models to capture observations are related to the model performance on precipitation. The precipitation-adjusted approach was applied, and the distribution of wet deposition was successfully revised.
Johannes Passig, Julian Schade, Robert Irsig, Lei Li, Xue Li, Zhen Zhou, Thomas Adam, and Ralf Zimmermann
Atmos. Meas. Tech., 14, 4171–4185, https://doi.org/10.5194/amt-14-4171-2021, https://doi.org/10.5194/amt-14-4171-2021, 2021
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Ships are major sources of air pollution; however, monitoring of ship emissions outside harbours is a challenging task. We optimized single-particle mass spectrometry (SPMS) for the detection of bunker fuel emissions and demonstrate the detection of individual ship plumes from more than 10 km in distance. The approach works independently of background air pollution and also when ships use exhaust-cleaning scrubbers. We discuss the potential and limits of SPMS-based monitoring of ship plumes.
Siqi Hou, Di Liu, Jingsha Xu, Tuan V. Vu, Xuefang Wu, Deepchandra Srivastava, Pingqing Fu, Linjie Li, Yele Sun, Athanasia Vlachou, Vaios Moschos, Gary Salazar, Sönke Szidat, André S. H. Prévôt, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 8273–8292, https://doi.org/10.5194/acp-21-8273-2021, https://doi.org/10.5194/acp-21-8273-2021, 2021
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This study provides a newly developed method which combines radiocarbon (14C) with organic tracers to enable source apportionment of primary and secondary fossil vs. non-fossil sources of carbonaceous aerosols at an urban and a rural site of Beijing. The source apportionment results were compared with those by chemical mass balance and AMS/ACSM-PMF methods. Correlations of WINSOC and WSOC with different sources of OC were also performed to elucidate the formation mechanisms of SOC.
Weiqi Xu, Masayuki Takeuchi, Chun Chen, Yanmei Qiu, Conghui Xie, Wanyun Xu, Nan Ma, Douglas R. Worsnop, Nga Lee Ng, and Yele Sun
Atmos. Meas. Tech., 14, 3693–3705, https://doi.org/10.5194/amt-14-3693-2021, https://doi.org/10.5194/amt-14-3693-2021, 2021
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Here we developed a method for estimation of particulate organic nitrates (pON) from the measurements of a high-resolution aerosol mass spectrometer coupled with a thermodenuder based on the volatility differences between inorganic nitrate and pON. The results generally had improvements in reducing negative values due to the influences of a high concentration of inorganic nitrate and a constant ratio of NO+ to NO2+ of organic nitrates (RON).
Jiangchuan Tao, Ye Kuang, Nan Ma, Juan Hong, Yele Sun, Wanyun Xu, Yanyan Zhang, Yao He, Qingwei Luo, Linhong Xie, Hang Su, and Yafang Cheng
Atmos. Chem. Phys., 21, 7409–7427, https://doi.org/10.5194/acp-21-7409-2021, https://doi.org/10.5194/acp-21-7409-2021, 2021
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The mechanism of secondary aerosol (SA) formation can be affected by relative humidity (RH) and has different influences on the particle CCN activity under different RH conditions. In the North China Plain, we find different responses of CCN activity and enhancements of CCN number concentration to SA formation under different RH conditions. In addition, variations of aerosol mixing state due to SA formation contribute some of the largest uncertainties in predicting CCN number concentration.
Jingsha Xu, Di Liu, Xuefang Wu, Tuan V. Vu, Yanli Zhang, Pingqing Fu, Yele Sun, Weiqi Xu, Bo Zheng, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 7321–7341, https://doi.org/10.5194/acp-21-7321-2021, https://doi.org/10.5194/acp-21-7321-2021, 2021
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Source apportionment of fine aerosols in an urban site of Beijing used a chemical mass balance (CMB) model. Seven primary sources (industrial/residential coal burning, biomass burning, gasoline/diesel vehicles, cooking and vegetative detritus) explained an average of 75.7 % and 56.1 % of fine OC in winter and summer, respectively. CMB was found to resolve more primary OA sources than AMS-PMF, but the latter apportioned more secondary OA sources.
Steven J. Campbell, Kate Wolfer, Battist Utinger, Joe Westwood, Zhi-Hui Zhang, Nicolas Bukowiecki, Sarah S. Steimer, Tuan V. Vu, Jingsha Xu, Nicholas Straw, Steven Thomson, Atallah Elzein, Yele Sun, Di Liu, Linjie Li, Pingqing Fu, Alastair C. Lewis, Roy M. Harrison, William J. Bloss, Miranda Loh, Mark R. Miller, Zongbo Shi, and Markus Kalberer
Atmos. Chem. Phys., 21, 5549–5573, https://doi.org/10.5194/acp-21-5549-2021, https://doi.org/10.5194/acp-21-5549-2021, 2021
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In this study, we quantify PM2.5 oxidative potential (OP), a metric widely suggested as a potential measure of particle toxicity, in Beijing in summer and winter using four acellular assays. We correlate PM2.5 OP with a comprehensive range of atmospheric and particle composition measurements, demonstrating inter-assay differences and seasonal variation of PM2.5 OP. Using multivariate statistical analysis, we highlight specific particle chemical components and sources that influence OP.
Long Peng, Lei Li, Guohua Zhang, Xubing Du, Xinming Wang, Ping'an Peng, Guoying Sheng, and Xinhui Bi
Atmos. Chem. Phys., 21, 5605–5613, https://doi.org/10.5194/acp-21-5605-2021, https://doi.org/10.5194/acp-21-5605-2021, 2021
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We build a novel system that utilizes an aerodynamic aerosol classifier (AAC) combined with a single-particle aerosol mass spectrometry (SPAMS) to simultaneously characterize the volume equivalent diameter (Dve), chemical compositions, and effective density (ρe) of individual particles in real time. A test of the AAC-SPAMS with both spherical and aspherical particles shows that the deviations between the measured and theoretical values are less than 6 %.
Weiqi Xu, Chun Chen, Yanmei Qiu, Ying Li, Zhiqiang Zhang, Eleni Karnezi, Spyros N. Pandis, Conghui Xie, Zhijie Li, Jiaxing Sun, Nan Ma, Wanyun Xu, Pingqing Fu, Zifa Wang, Jiang Zhu, Douglas R. Worsnop, Nga Lee Ng, and Yele Sun
Atmos. Chem. Phys., 21, 5463–5476, https://doi.org/10.5194/acp-21-5463-2021, https://doi.org/10.5194/acp-21-5463-2021, 2021
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Here aerosol volatility and viscosity at a rural site (Gucheng) and an urban site (Beijing) in the North China Plain (NCP) were investigated in summer and winter. Our results showed that organic aerosol (OA) in winter in the NCP is more volatile than that in summer due to enhanced primary emissions from coal combustion and biomass burning. We also found that OA existed mainly as a solid in winter in Beijing but as semisolids in Beijing in summer and Gucheng in winter.
Santosh Kumar Verma, Kimitaka Kawamura, Fei Yang, Pingqing Fu, Yugo Kanaya, and Zifa Wang
Atmos. Chem. Phys., 21, 4959–4978, https://doi.org/10.5194/acp-21-4959-2021, https://doi.org/10.5194/acp-21-4959-2021, 2021
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We studied aerosol samples collected in autumn 2007 with day and night intervals in a rural site of Mangshan, north of Beijing, for sugar compounds (SCs) that are abundant organic aerosol components and can influence the air quality and climate. We found higher concentrations of biomass burning (BB) products at nighttime than daytime, whereas pollen tracers and other SCs showed an opposite diurnal trend, because this site is meteorologically characterized by a mountain/valley breeze.
Tabish Umar Ansari, Oliver Wild, Edmund Ryan, Ying Chen, Jie Li, and Zifa Wang
Atmos. Chem. Phys., 21, 4471–4485, https://doi.org/10.5194/acp-21-4471-2021, https://doi.org/10.5194/acp-21-4471-2021, 2021
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We use novel modelling approaches to quantify the lingering effects of 1 d local and regional emission controls on subsequent days, the effects of longer continuous emission controls of individual sectors over different regions, and the effects of combined emission controls of multiple sectors and regions on air quality in Beijing under varying weather conditions to inform precise short-term emission control policies for avoiding heavy haze pollution in Beijing.
Lei Kong, Xiao Tang, Jiang Zhu, Zifa Wang, Jianjun Li, Huangjian Wu, Qizhong Wu, Huansheng Chen, Lili Zhu, Wei Wang, Bing Liu, Qian Wang, Duohong Chen, Yuepeng Pan, Tao Song, Fei Li, Haitao Zheng, Guanglin Jia, Miaomiao Lu, Lin Wu, and Gregory R. Carmichael
Earth Syst. Sci. Data, 13, 529–570, https://doi.org/10.5194/essd-13-529-2021, https://doi.org/10.5194/essd-13-529-2021, 2021
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China's air pollution has changed substantially since 2013. Here we have developed a 6-year-long high-resolution air quality reanalysis dataset over China from 2013 to 2018 to illustrate such changes and to provide a basic dataset for relevant studies. Surface fields of PM2.5, PM10, SO2, NO2, CO, and O3 concentrations are provided, and the evaluation results indicate that the reanalysis dataset has excellent performance in reproducing the magnitude and variation of air pollution in China.
Lei Liu, Jian Zhang, Yinxiao Zhang, Yuanyuan Wang, Liang Xu, Qi Yuan, Dantong Liu, Yele Sun, Pingqing Fu, Zongbo Shi, and Weijun Li
Atmos. Chem. Phys., 21, 2251–2265, https://doi.org/10.5194/acp-21-2251-2021, https://doi.org/10.5194/acp-21-2251-2021, 2021
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We found that large numbers of light-absorbing primary organic particles with high viscosity, especially tarballs, from domestic coal and biomass burning occurred in rural and even urban hazes in the winter of North China. For the first time, we characterized the atmospheric aging process of these burning-related primary organic particles by microscopic analysis and further evaluated their light absorption enhancement resulting from the “lensing effect” of secondary inorganic coatings.
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 2125–2147, https://doi.org/10.5194/acp-21-2125-2021, https://doi.org/10.5194/acp-21-2125-2021, 2021
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To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2 and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model, which shows that under low NO conditions, there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Liya Ma, Yujiao Zhu, Mei Zheng, Yele Sun, Lei Huang, Xiaohuan Liu, Yang Gao, Yanjie Shen, Huiwang Gao, and Xiaohong Yao
Atmos. Chem. Phys., 21, 183–200, https://doi.org/10.5194/acp-21-183-2021, https://doi.org/10.5194/acp-21-183-2021, 2021
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In this study, we investigate three patterns of new particles growing to CCN (cloud condensation nuclei) size, i.e., one-stage growth and two-stage growth-A and growth-B patterns. Combining the observations of gaseous pollutants and measured or modeled particulate chemical species, the three growth patterns were discussed regarding the spatial heterogeneity, formation of secondary aerosols, and evaporation of semivolatile particulates as was the survival probability of new particles to CCN size.
Rutambhara Joshi, Dantong Liu, Eiko Nemitz, Ben Langford, Neil Mullinger, Freya Squires, James Lee, Yunfei Wu, Xiaole Pan, Pingqing Fu, Simone Kotthaus, Sue Grimmond, Qiang Zhang, Ruili Wu, Oliver Wild, Michael Flynn, Hugh Coe, and James Allan
Atmos. Chem. Phys., 21, 147–162, https://doi.org/10.5194/acp-21-147-2021, https://doi.org/10.5194/acp-21-147-2021, 2021
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Black carbon (BC) is a component of particulate matter which has significant effects on climate and human health. Sources of BC include biomass burning, transport, industry and domestic cooking and heating. In this study, we measured BC emissions in Beijing, finding a dominance of traffic emissions over all other sources. The quantitative method presented here has benefits for revising widely used emissions inventories and for understanding BC sources with impacts on air quality and climate.
Hajime Akimoto, Tatsuya Nagashima, Natsumi Kawano, Li Jie, Joshua S. Fu, and Zifa Wang
Atmos. Chem. Phys., 20, 15003–15014, https://doi.org/10.5194/acp-20-15003-2020, https://doi.org/10.5194/acp-20-15003-2020, 2020
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In order to perform proper model simulation of ozone near the ground in the coastal area of northeastern Asia, it has been found that it is very important to select appropriate dry deposition velocities of ozone on the oceanic water of specific area of the northwestern Pacific. Empirical measurement of the mixing ratios and dry deposition flux of ozone over the ocean in this area is highly recommended.
Eloise J. Slater, Lisa K. Whalley, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Leigh R. Crilley, Louisa Kramer, William Bloss, Tuan Vu, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 20, 14847–14871, https://doi.org/10.5194/acp-20-14847-2020, https://doi.org/10.5194/acp-20-14847-2020, 2020
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The paper details atmospheric chemistry in a megacity (Beijing), focussing on radicals which mediate the formation of secondary pollutants such as ozone and particles. Highly polluted conditions were experienced, including the highest ever levels of nitric oxide (NO), with simultaneous radical measurements. Radical concentrations were large during "haze" events, demonstrating active photochemistry. Modelling showed that our understanding of the chemistry at high NOx levels is incomplete.
Jingsha Xu, Shaojie Song, Roy M. Harrison, Congbo Song, Lianfang Wei, Qiang Zhang, Yele Sun, Lu Lei, Chao Zhang, Xiaohong Yao, Dihui Chen, Weijun Li, Miaomiao Wu, Hezhong Tian, Lining Luo, Shengrui Tong, Weiran Li, Junling Wang, Guoliang Shi, Yanqi Huangfu, Yingze Tian, Baozhu Ge, Shaoli Su, Chao Peng, Yang Chen, Fumo Yang, Aleksandra Mihajlidi-Zelić, Dragana Đorđević, Stefan J. Swift, Imogen Andrews, Jacqueline F. Hamilton, Ye Sun, Agung Kramawijaya, Jinxiu Han, Supattarachai Saksakulkrai, Clarissa Baldo, Siqi Hou, Feixue Zheng, Kaspar R. Daellenbach, Chao Yan, Yongchun Liu, Markku Kulmala, Pingqing Fu, and Zongbo Shi
Atmos. Meas. Tech., 13, 6325–6341, https://doi.org/10.5194/amt-13-6325-2020, https://doi.org/10.5194/amt-13-6325-2020, 2020
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An interlaboratory comparison was conducted for the first time to examine differences in water-soluble inorganic ions (WSIIs) measured by 10 labs using ion chromatography (IC) and by two online aerosol chemical speciation monitor (ACSM) methods. Major ions including SO42−, NO3− and NH4+ agreed well in 10 IC labs and correlated well with ACSM data. WSII interlab variability strongly affected aerosol acidity results based on ion balance, but aerosol pH computed by ISORROPIA II was very similar.
Chaomin Wang, Bin Yuan, Caihong Wu, Sihang Wang, Jipeng Qi, Baolin Wang, Zelong Wang, Weiwei Hu, Wei Chen, Chenshuo Ye, Wenjie Wang, Yele Sun, Chen Wang, Shan Huang, Wei Song, Xinming Wang, Suxia Yang, Shenyang Zhang, Wanyun Xu, Nan Ma, Zhanyi Zhang, Bin Jiang, Hang Su, Yafang Cheng, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 20, 14123–14138, https://doi.org/10.5194/acp-20-14123-2020, https://doi.org/10.5194/acp-20-14123-2020, 2020
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We utilized a novel online mass spectrometry method to measure the total concentration of higher alkanes at each carbon number at two different sites in China, allowing us to take into account SOA contributions from all isomers for higher alkanes. We found that higher alkanes account for significant fractions of SOA formation at the two sites. The contributions are comparable to or even higher than single-ring aromatics, the most-recognized SOA precursors in urban air.
Yuzhen Fu, Qinhao Lin, Guohua Zhang, Yuxiang Yang, Yiping Yang, Xiufeng Lian, Long Peng, Feng Jiang, Xinhui Bi, Lei Li, Yuanyuan Wang, Duohong Chen, Jie Ou, Xinming Wang, Ping'an Peng, Jianxi Zhu, and Guoying Sheng
Atmos. Chem. Phys., 20, 14063–14075, https://doi.org/10.5194/acp-20-14063-2020, https://doi.org/10.5194/acp-20-14063-2020, 2020
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Based on the analysis of the morphology and mixing structure of the activated and unactivated particles, our results emphasize the role of in-cloud processes in the chemistry and microphysical properties of individual activated particles. Given that organic coatings may determine the particle hygroscopicity and heterogeneous chemical reactivity, the increase of OM-shelled particles upon in-cloud processes should have considerable implications for their evolution and climate impact.
Junfeng Wang, Jianhuai Ye, Dantong Liu, Yangzhou Wu, Jian Zhao, Weiqi Xu, Conghui Xie, Fuzhen Shen, Jie Zhang, Paul E. Ohno, Yiming Qin, Xiuyong Zhao, Scot T. Martin, Alex K. Y. Lee, Pingqing Fu, Daniel J. Jacob, Qi Zhang, Yele Sun, Mindong Chen, and Xinlei Ge
Atmos. Chem. Phys., 20, 14091–14102, https://doi.org/10.5194/acp-20-14091-2020, https://doi.org/10.5194/acp-20-14091-2020, 2020
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We compared the organics in total submicron matter and those coated on BC cores during summertime in Beijing and found large differences between them. Traffic-related OA was associated significantly with BC, while cooking-related OA did not coat BC. In addition, a factor likely originated from primary biomass burning OA was only identified in BC-containing particles. Such a unique BBOA requires further field and laboratory studies to verify its presence and elucidate its properties and impacts.
Yongjoo Choi, Yugo Kanaya, Masayuki Takigawa, Chunmao Zhu, Seung-Myung Park, Atsushi Matsuki, Yasuhiro Sadanaga, Sang-Woo Kim, Xiaole Pan, and Ignacio Pisso
Atmos. Chem. Phys., 20, 13655–13670, https://doi.org/10.5194/acp-20-13655-2020, https://doi.org/10.5194/acp-20-13655-2020, 2020
Jing Cai, Biwu Chu, Lei Yao, Chao Yan, Liine M. Heikkinen, Feixue Zheng, Chang Li, Xiaolong Fan, Shaojun Zhang, Daoyuan Yang, Yonghong Wang, Tom V. Kokkonen, Tommy Chan, Ying Zhou, Lubna Dada, Yongchun Liu, Hong He, Pauli Paasonen, Joni T. Kujansuu, Tuukka Petäjä, Claudia Mohr, Juha Kangasluoma, Federico Bianchi, Yele Sun, Philip L. Croteau, Douglas R. Worsnop, Veli-Matti Kerminen, Wei Du, Markku Kulmala, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 20, 12721–12740, https://doi.org/10.5194/acp-20-12721-2020, https://doi.org/10.5194/acp-20-12721-2020, 2020
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By applying both OA PMF and size PMF at the same urban measurement site in Beijing, similar particle source types, including vehicular emissions, cooking emissions and secondary formation-related sources, were resolved by both frameworks and agreed well. It is also found that in the absence of new particle formation, vehicular and cooking emissions dominate the particle number concentration, while secondary particulate matter governed PM2.5 mass during spring and summer in Beijing.
Ruqian Miao, Qi Chen, Yan Zheng, Xi Cheng, Yele Sun, Paul I. Palmer, Manish Shrivastava, Jianping Guo, Qiang Zhang, Yuhan Liu, Zhaofeng Tan, Xuefei Ma, Shiyi Chen, Limin Zeng, Keding Lu, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 12265–12284, https://doi.org/10.5194/acp-20-12265-2020, https://doi.org/10.5194/acp-20-12265-2020, 2020
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In this study we evaluated the model performances for simulating secondary inorganic aerosol (SIA) and organic aerosol (OA) in PM2.5 in China against comprehensive datasets. The potential biases from factors related to meteorology, emission, chemistry, and atmospheric removal are systematically investigated. This study provides a comprehensive understanding of modeling PM2.5, which is important for studies on the effectiveness of emission control strategies.
Hwajin Kim, Qi Zhang, and Yele Sun
Atmos. Chem. Phys., 20, 11527–11550, https://doi.org/10.5194/acp-20-11527-2020, https://doi.org/10.5194/acp-20-11527-2020, 2020
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Severe spring haze and influences of long-range transport in the Seoul metropolitan area (SMA) in March 2019 were investigated. Simultaneous downwind (SMA) and upwind (Beijing) measurements using AMS and ACSM over the same period showed that PM species can be transported in approximately 2 d. Nitrate was the most responsible, and sulfate and two regional-transport-influenced SOAs also contributed. Enhancement of Pb also showed that the haze in the SMA was influenced by the regional transport.
Baozhu Ge, Syuichi Itahashi, Keiichi Sato, Danhui Xu, Junhua Wang, Fan Fan, Qixin Tan, Joshua S. Fu, Xuemei Wang, Kazuyo Yamaji, Tatsuya Nagashima, Jie Li, Mizuo Kajino, Hong Liao, Meigen Zhang, Zhe Wang, Meng Li, Jung-Hun Woo, Junichi Kurokawa, Yuepeng Pan, Qizhong Wu, Xuejun Liu, and Zifa Wang
Atmos. Chem. Phys., 20, 10587–10610, https://doi.org/10.5194/acp-20-10587-2020, https://doi.org/10.5194/acp-20-10587-2020, 2020
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Performances of the simulated deposition for different reduced N (Nr) species in China were conducted with the Model Inter-Comparison Study for Asia. Results showed that simulated wet deposition of oxidized N was overestimated in northeastern China and underestimated in south China, but Nr was underpredicted in all regions by all models. Oxidized N has larger uncertainties than Nr, indicating that the chemical reaction process is one of the most importance factors affecting model performance.
Wanyu Zhao, Hong Ren, Kimitaka Kawamura, Huiyun Du, Xueshun Chen, Siyao Yue, Qiaorong Xie, Lianfang Wei, Ping Li, Xin Zeng, Shaofei Kong, Yele Sun, Zifa Wang, and Pingqing Fu
Atmos. Chem. Phys., 20, 10331–10350, https://doi.org/10.5194/acp-20-10331-2020, https://doi.org/10.5194/acp-20-10331-2020, 2020
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Our observations provide detailed information on the abundance and vertical distribution of dicarboxylic acids, oxoacids and α-dicarbonyls in PM2.5 collected at three heights based on a 325 m meteorological tower in Beijing in summer. Our results demonstrate that organic acids at the ground surface are largely associated with local traffic emissions, while long-range atmospheric transport followed by photochemical ageing contributes more in the urban boundary layer than the ground surface.
Shengqiang Zhu, Lei Li, Shurong Wang, Mei Li, Yaxi Liu, Xiaohui Lu, Hong Chen, Lin Wang, Jianmin Chen, Zhen Zhou, Xin Yang, and Xiaofei Wang
Atmos. Meas. Tech., 13, 4111–4121, https://doi.org/10.5194/amt-13-4111-2020, https://doi.org/10.5194/amt-13-4111-2020, 2020
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Single-particle aerosol mass spectrometry (SPAMS) is widely used to detect chemical compositions and sizes of individual aerosol particles. However, it has a major issue: the mass accuracy of high-resolution SPAMS is relatively low. Here we developed an automatic linear calibration method to greatly improve the mass accuracy of SPAMS spectra so that the elemental compositions of organic peaks, such as Cx, CxHy, CxHyOz and CxHyNO peaks, can be directly identified just based on their m / z values.
Junchen Guo, Shengzhen Zhou, Mingfu Cai, Jun Zhao, Wei Song, Weixiong Zhao, Weiwei Hu, Yele Sun, Yao He, Chengqiang Yang, Xuezhe Xu, Zhisheng Zhang, Peng Cheng, Qi Fan, Jian Hang, Shaojia Fan, Xinming Wang, and Xuemei Wang
Atmos. Chem. Phys., 20, 7595–7615, https://doi.org/10.5194/acp-20-7595-2020, https://doi.org/10.5194/acp-20-7595-2020, 2020
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We characterized non-refractory submicron particulate matter (PM1.0) during winter in Guangzhou, south China. Chemical composition and key sources of ambient PM1.0 are revealed, highlighting the significant role of SOA. The relationship with SOA and peroxy radicals indicated gas-phase oxidation contributed predominantly to SOA formation during non-pollution periods, while heterogeneous/multiphase reactions played more important roles in SOA formation during pollution periods.
Daniel J. Bryant, William J. Dixon, James R. Hopkins, Rachel E. Dunmore, Kelly L. Pereira, Marvin Shaw, Freya A. Squires, Thomas J. Bannan, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Bin Ouyang, Tianqu Cui, Jason D. Surratt, Di Liu, Zongbo Shi, Roy Harrison, Yele Sun, Weiqi Xu, Alastair C. Lewis, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 20, 7531–7552, https://doi.org/10.5194/acp-20-7531-2020, https://doi.org/10.5194/acp-20-7531-2020, 2020
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Using the chemical composition of offline filter samples, we report that a large share of oxidized organic aerosol in Beijing during summer is due to isoprene secondary organic aerosol (iSOA). iSOA organosulfates showed a strong correlation with the product of ozone and particulate sulfate. This highlights the role of both photochemistry and the availability of particulate sulfate in heterogeneous reactions and further demonstrates that iSOA formation is controlled by anthropogenic emissions.
Jiani Tan, Joshua S. Fu, Gregory R. Carmichael, Syuichi Itahashi, Zhining Tao, Kan Huang, Xinyi Dong, Kazuyo Yamaji, Tatsuya Nagashima, Xuemei Wang, Yiming Liu, Hyo-Jung Lee, Chuan-Yao Lin, Baozhu Ge, Mizuo Kajino, Jia Zhu, Meigen Zhang, Hong Liao, and Zifa Wang
Atmos. Chem. Phys., 20, 7393–7410, https://doi.org/10.5194/acp-20-7393-2020, https://doi.org/10.5194/acp-20-7393-2020, 2020
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This study evaluated the performance of 12 chemical transport models from MICS-Asia III for predicting the particulate matter (PM) over East Asia. Four model processes were investigated as the possible reasons for model bias with measurements and the factors causing inconsistent predictions of PM from different models: (1) model inputs, (2) gas–particle conversion, (3) dust emission modules and (4) removal mechanisms (wet and dry depositions). The influence of each process was discussed.
Jingyi Li, Haowen Zhang, Qi Ying, Zhijun Wu, Yanli Zhang, Xinming Wang, Xinghua Li, Yele Sun, Min Hu, Yuanhang Zhang, and Jianlin Hu
Atmos. Chem. Phys., 20, 7291–7306, https://doi.org/10.5194/acp-20-7291-2020, https://doi.org/10.5194/acp-20-7291-2020, 2020
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Large gaps still exist in modeled and observed secondary organic aerosol (SOA) mass loading and properties. Here we investigated the impacts of water partitioning into organic aerosol and nonideality of the organic–water mixture on SOA over eastern China using a regional 3D model. SOA is increased more significantly in humid and hot environments. Increases in SOA further cause an enhancement of the cooling effects of aerosols. It is crucial to consider the above processes in modeling SOA.
Weiqi Xu, Yao He, Yanmei Qiu, Chun Chen, Conghui Xie, Lu Lei, Zhijie Li, Jiaxing Sun, Junyao Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Meas. Tech., 13, 3205–3219, https://doi.org/10.5194/amt-13-3205-2020, https://doi.org/10.5194/amt-13-3205-2020, 2020
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We characterized mass spectral features of organic aerosol (OA) and water-soluble OA (WSOA) from 21 cooking, crop straw, wood, and coal burning experiments using aerosol mass spectrometers with standard and capture vaporizers, and we demonstrated the applications of source spectral profiles in improving source apportionment of ambient OA at a highly polluted rural site in the North China Plain in winter.
Jing Yang, Wanyu Zhao, Lianfang Wei, Qiang Zhang, Yue Zhao, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Xiaole Pan, Yele Sun, Zifa Wang, Cong-Qiang Liu, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 20, 6841–6860, https://doi.org/10.5194/acp-20-6841-2020, https://doi.org/10.5194/acp-20-6841-2020, 2020
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Our observations provide novel detailed information on the atmospheric abundances and spatial distributions of dicarboxylic acids, oxoacids, and α-dicarbonyls in marine aerosols collected from the South China Sea to the East Indian Ocean. Our results demonstrate that the continental outflow of both biogenic and anthropogenic precursors followed by photochemical aging is one of the main sources and formation processes of marine organic aerosols over the tropical oceanic regions.
Qiaorong Xie, Sihui Su, Shuang Chen, Yisheng Xu, Dong Cao, Jing Chen, Lujie Ren, Siyao Yue, Wanyu Zhao, Yele Sun, Zifa Wang, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, Guibin Jiang, Cong-Qiang Liu, and Pingqing Fu
Atmos. Chem. Phys., 20, 6803–6820, https://doi.org/10.5194/acp-20-6803-2020, https://doi.org/10.5194/acp-20-6803-2020, 2020
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Current knowledge on firework-related organic aerosols is very limited. Here the detailed molecular composition of organics in urban aerosols was characterized using ultrahigh-resolution FT-ICR mass spectrometry. Our findings highlight that firework emission leads to a sharp increase in CHO, CHNO, and CHOS containing high-molecular-weight species, particularly aromatic-like substances, which affect the physicochemical properties such as the light absorption and health effects of urban aerosols.
Bojiang Su, Zeming Zhuo, Yuzhen Fu, Wei Sun, Ying Chen, Xubing Du, Yuxiang Yang, Si Wu, Fugui Huang, Duohong Chen, Lei Li, Guohua Zhang, Xinhui Bi, and Zhen Zhou
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-443, https://doi.org/10.5194/acp-2020-443, 2020
Revised manuscript not accepted
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In this study, chemical composition, mixing state and aging degree of individual sea spray aerosol (SSA) were measured by single particle aerosol mass spectrometer (SPAMS) during summer monsoon in southern China. Our results show that organic acids has significant contribution to chloride depletion of SSA. A class of biological SSA underwent relative weak chloride depletion compare to other SSA types, which may attribute to organic species (i.e. organic nitrogen and biological phosphate).
Shengzhen Zhou, Luolin Wu, Junchen Guo, Weihua Chen, Xuemei Wang, Jun Zhao, Yafang Cheng, Zuzhao Huang, Jinpu Zhang, Yele Sun, Pingqing Fu, Shiguo Jia, Jun Tao, Yanning Chen, and Junxia Kuang
Atmos. Chem. Phys., 20, 6435–6453, https://doi.org/10.5194/acp-20-6435-2020, https://doi.org/10.5194/acp-20-6435-2020, 2020
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In this work, measurements of size-segregated aerosols were conducted at three altitudes (ground level, 118 m, and 488 m) on the 610 m high Canton Tower in southern China. Vertical variations of PM and size-segregated chemical compositions were investigated. The results indicated that meteorological parameters and atmospheric aqueous and heterogeneous reactions together led to aerosol formation and haze episodes in the Pearl River Delta region during the measurement periods.
Hang Liu, Xiaole Pan, Dantong Liu, Xiaoyong Liu, Xueshun Chen, Yu Tian, Yele Sun, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 20, 5771–5785, https://doi.org/10.5194/acp-20-5771-2020, https://doi.org/10.5194/acp-20-5771-2020, 2020
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The bare black carbon (BC) was in a fractal structure. With coating thickness increasing, BC changed from a fractal structure to a core–shell structure. In the ambient atmosphere, plenty of BC particles were not in a perfect core–shell structure. This study brought attention to the combined effects of morphology and coating thickness on the absorption enhancement of BC-containing particles, which is helpful for determining the climatic effects of BC.
Fanhao Meng, Min Qin, Ke Tang, Jun Duan, Wu Fang, Shuaixi Liang, Kaidi Ye, Pinhua Xie, Yele Sun, Conghui Xie, Chunxiang Ye, Pingqing Fu, Jianguo Liu, and Wenqing Liu
Atmos. Chem. Phys., 20, 5071–5092, https://doi.org/10.5194/acp-20-5071-2020, https://doi.org/10.5194/acp-20-5071-2020, 2020
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Nitrous acid (HONO), a major precursor of the OH radical, plays a key role in atmospheric chemistry, but its sources are still debated. The first high-resolution vertical measurements of HONO and NO2 were conducted in Beijing to investigate the nocturnal sources of HONO at different stages of pollution. The ground surface dominated HONO production by heterogeneous conversion of NO2 during clean episodes, but the aerosol production was an important nighttime HONO source during haze episodes.
Chenjie Yu, Dantong Liu, Kurtis Broda, Rutambhara Joshi, Jason Olfert, Yele Sun, Pingqing Fu, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 20, 3645–3661, https://doi.org/10.5194/acp-20-3645-2020, https://doi.org/10.5194/acp-20-3645-2020, 2020
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This study presents the first atmospheric application of a new morphology-independent measurement for the quantification of the mixing state of rBC-containing particles in urban Beijing as part of the UK–China APHH campaign. An inversion method has been applied for better quantification of rBC mixing state. The mass-resolved rBC mixing state information presented here has implications for detailed models of BC, its optical properties and its atmospheric life cycle.
Shaofeng Xu, Lujie Ren, Yunchao Lang, Shengjie Hou, Hong Ren, Lianfang Wei, Libin Wu, Junjun Deng, Wei Hu, Xiaole Pan, Yele Sun, Zifa Wang, Hang Su, Yafang Cheng, and Pingqing Fu
Atmos. Chem. Phys., 20, 3623–3644, https://doi.org/10.5194/acp-20-3623-2020, https://doi.org/10.5194/acp-20-3623-2020, 2020
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Current knowledge on the size distribution of biogenic primary organic aerosols in urban regions with heavy haze pollution is very limited. Here we performed a year-round study focusing on the organic molecular composition of size-segregated aerosol samples collected in urban Beijing during haze and non-haze days to elucidate the seasonal contributions of biomass burning, fungal spores, and plant debris to organic carbon as well as the influences from local emissions and long-range transport.
Leigh R. Crilley, Ajit Singh, Louisa J. Kramer, Marvin D. Shaw, Mohammed S. Alam, Joshua S. Apte, William J. Bloss, Lea Hildebrandt Ruiz, Pingqing Fu, Weiqi Fu, Shahzad Gani, Michael Gatari, Evgenia Ilyinskaya, Alastair C. Lewis, David Ng'ang'a, Yele Sun, Rachel C. W. Whitty, Siyao Yue, Stuart Young, and Francis D. Pope
Atmos. Meas. Tech., 13, 1181–1193, https://doi.org/10.5194/amt-13-1181-2020, https://doi.org/10.5194/amt-13-1181-2020, 2020
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There is considerable interest in using low-cost optical particle counters (OPCs) for particle mass measurements; however, there is no agreed upon method with respect to calibration. Here we exploit a number of datasets globally to demonstrate that particle composition and relative humidity are the key factors affecting measured concentrations from a low-cost OPC, and we present a simple correction methodology that corrects for this influence.
Lu Lei, Conghui Xie, Dawei Wang, Yao He, Qingqing Wang, Wei Zhou, Wei Hu, Pingqing Fu, Yong Chen, Xiaole Pan, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 20, 2877–2890, https://doi.org/10.5194/acp-20-2877-2020, https://doi.org/10.5194/acp-20-2877-2020, 2020
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We characterized aerosol composition and sources near two steel plants in a coastal region in fall and spring seasons. Our results showed substantially different aerosol composition and sources between the two seasons. We observed significant impacts of steel plant emissions on aerosol chemistry nearby, and we found that aerosol particles emitted from the steel plants were dominated by ammonium sulfate/bisulfate; NOx/CO and NOx/SO2 were distinct from those in the absence of industrial plumes.
Syuichi Itahashi, Baozhu Ge, Keiichi Sato, Joshua S. Fu, Xuemei Wang, Kazuyo Yamaji, Tatsuya Nagashima, Jie Li, Mizuo Kajino, Hong Liao, Meigen Zhang, Zhe Wang, Meng Li, Junichi Kurokawa, Gregory R. Carmichael, and Zifa Wang
Atmos. Chem. Phys., 20, 2667–2693, https://doi.org/10.5194/acp-20-2667-2020, https://doi.org/10.5194/acp-20-2667-2020, 2020
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This study gives an overview of acid deposition from the Model Inter-Comparison Study for Asia (MICS-Asia) phase III. Wet deposition simulated by a total of nine models is evaluated with observation data from the Acid Deposition Monitoring Network in East Asia (EANET). The total deposition maps comparing to emissions over Asia are presented. To seek a way to improve the model performance, ensemble approaches and the precipitation-adjusted method are discussed.
Ying Chen, Viacheslav Kozlovskiy, Xubing Du, Jinnuo Lv, Sergei Nikiforov, Jiajun Yu, Alexander Kolosov, Wei Gao, Zhen Zhou, Zhengxu Huang, and Lei Li
Atmos. Meas. Tech., 13, 941–949, https://doi.org/10.5194/amt-13-941-2020, https://doi.org/10.5194/amt-13-941-2020, 2020
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Ion delayed extraction technique in single particle mass spectrometry has been found to improve the mass resolution of instruments. Through further research, it was found that it can improve the aerosol particle detection efficiency because it can eliminate the influence of the electrical field on the charged aerosol trajectory so that more effective data can be obtained in a short time in laboratory or field atmospheric aerosol research, especially in low-concentration aerosol sample analysis.
Jia Yin Sun, Cheng Wu, Dui Wu, Chunlei Cheng, Mei Li, Lei Li, Tao Deng, Jian Zhen Yu, Yong Jie Li, Qianni Zhou, Yue Liang, Tianlin Sun, Lang Song, Peng Cheng, Wenda Yang, Chenglei Pei, Yanning Chen, Yanxiang Cen, Huiqing Nian, and Zhen Zhou
Atmos. Chem. Phys., 20, 2445–2470, https://doi.org/10.5194/acp-20-2445-2020, https://doi.org/10.5194/acp-20-2445-2020, 2020
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Atmospheric aging processes (AAPs) can lead to black carbon (BC) light absorption enhancement (Eabs), which remained poorly characterized at a long timescale. By applying a newly developed approach, the minimum R squared method (MRS), this study investigated the temporal variations of BC Eabs at both seasonal and diel scales in an urban environment. Factors affecting the temporal variability of BC Eabs were also analyzed, including variability in emission sources and various types of AAPs.
Zhining Tao, Mian Chin, Meng Gao, Tom Kucsera, Dongchul Kim, Huisheng Bian, Jun-ichi Kurokawa, Yuesi Wang, Zirui Liu, Gregory R. Carmichael, Zifa Wang, and Hajime Akimoto
Atmos. Chem. Phys., 20, 2319–2339, https://doi.org/10.5194/acp-20-2319-2020, https://doi.org/10.5194/acp-20-2319-2020, 2020
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One goal of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III is to identify strengths and weaknesses of current air quality models to provide insights into reducing uncertainties. This study identified that a 15 km grid would be the optimal horizontal resolution in terms of performance and resource usage to capture average and extreme air quality over East Asia and is thus suggested for use in future MICS-Asia modeling activities if the investigation domain remains the same.
Meng Gao, Zirui Liu, Bo Zheng, Dongsheng Ji, Peter Sherman, Shaojie Song, Jinyuan Xin, Cheng Liu, Yuesi Wang, Qiang Zhang, Jia Xing, Jingkun Jiang, Zifa Wang, Gregory R. Carmichael, and Michael B. McElroy
Atmos. Chem. Phys., 20, 1497–1505, https://doi.org/10.5194/acp-20-1497-2020, https://doi.org/10.5194/acp-20-1497-2020, 2020
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We quantified the relative influences of anthropogenic emissions and meteorological conditions on PM2.5 concentrations in Beijing over the winters of 2002–2016. Meteorological conditions over the study period would have led to an increase of haze in Beijing, but the strict emission control measures have suppressed the unfavorable influences of the recent climate.
Guohua Zhang, Xiufeng Lian, Yuzhen Fu, Qinhao Lin, Lei Li, Wei Song, Zhanyong Wang, Mingjin Tang, Duohong Chen, Xinhui Bi, Xinming Wang, and Guoying Sheng
Atmos. Chem. Phys., 20, 1469–1481, https://doi.org/10.5194/acp-20-1469-2020, https://doi.org/10.5194/acp-20-1469-2020, 2020
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Seasonal atmospheric processing of NOCs was investigated using single-particle mass spectrometry in urban Guangzhou. The abundance of NOCs was found to be strongly enhanced by internal mixing with photochemically produced secondary oxidized organics. A multiple linear regression analysis and a positive matrix factorization analysis were performed to predict the relative abundance of NOCs. More than 70 % of observed NOCs could be well explained by oxidized organics and ammonium.
Meng Gao, Zhiwei Han, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Meng Li, Jung-Hun Woo, Qiang Zhang, Yafang Cheng, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 20, 1147–1161, https://doi.org/10.5194/acp-20-1147-2020, https://doi.org/10.5194/acp-20-1147-2020, 2020
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Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative feedbacks. This paper discusses the estimates of aerosol radiative forcing, aerosol feedbacks, and possible causes for the differences among the models.
Xinxin Fan, Jieyao Liu, Fang Zhang, Lu Chen, Don Collins, Weiqi Xu, Xiaoai Jin, Jingye Ren, Yuying Wang, Hao Wu, Shangze Li, Yele Sun, and Zhanqing Li
Atmos. Chem. Phys., 20, 915–929, https://doi.org/10.5194/acp-20-915-2020, https://doi.org/10.5194/acp-20-915-2020, 2020
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Aerosol effects on visibility and climate are influenced by their hygroscopicity. By contrasting data from two techniques between summer and winter in Beijing, we investigate the effect of aerosol aging, mixing state, and local sources on its hygroscopicity. We revealed that inappropriate use of the density of BC and organics results in large uncertainty in calculating aerosols hygroscopicity. Our results are helpful for parameterization in models.
Xiaoai Jin, Yuying Wang, Zhanqing Li, Fang Zhang, Weiqi Xu, Yele Sun, Xinxin Fan, Guangyu Chen, Hao Wu, Jingye Ren, Qiuyan Wang, and Maureen Cribb
Atmos. Chem. Phys., 20, 901–914, https://doi.org/10.5194/acp-20-901-2020, https://doi.org/10.5194/acp-20-901-2020, 2020
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In this study the aerosol liquid water content (ALWC) is determined from aerosol hygroscopic growth factor (GF) measurement (ALWCHTDMA) and also simulated by the ISORROPIA II thermodynamic model (ALWCISO). We found that ALWC contributed by organics (ALWCOrg) accounts for 30 % ± 22 % of the total ALWC in winter in Beijing. A case study reveals that ALWCOrg plays an important role in the formation of secondary aerosols through multiphase reactions at the initial stage of a heavy-haze episode.
Ye Kuang, Yao He, Wanyun Xu, Pusheng Zhao, Yafang Cheng, Gang Zhao, Jiangchuan Tao, Nan Ma, Hang Su, Yanyan Zhang, Jiayin Sun, Peng Cheng, Wenda Yang, Shaobin Zhang, Cheng Wu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 865–880, https://doi.org/10.5194/acp-20-865-2020, https://doi.org/10.5194/acp-20-865-2020, 2020
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A new method was developed to calculate hygroscopicity parameter κ of organic aerosols (κOA) based on aerosol light-scattering measurements and bulk aerosol chemical-composition measurements. Derived high-time-resolution κOA varied in a wide range (near 0 to 0.25), and the organic aerosol oxidation degree significantly impacts variations in κOA. Distinct diurnal variation in κOA is found, and its relationship with oxygenated organic aerosol is discussed.
Lei Kong, Xiao Tang, Jiang Zhu, Zifa Wang, Joshua S. Fu, Xuemei Wang, Syuichi Itahashi, Kazuyo Yamaji, Tatsuya Nagashima, Hyo-Jung Lee, Cheol-Hee Kim, Chuan-Yao Lin, Lei Chen, Meigen Zhang, Zhining Tao, Jie Li, Mizuo Kajino, Hong Liao, Zhe Wang, Kengo Sudo, Yuesi Wang, Yuepeng Pan, Guiqian Tang, Meng Li, Qizhong Wu, Baozhu Ge, and Gregory R. Carmichael
Atmos. Chem. Phys., 20, 181–202, https://doi.org/10.5194/acp-20-181-2020, https://doi.org/10.5194/acp-20-181-2020, 2020
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Evaluation and uncertainty investigation of NO2, CO and NH3 modeling over China were conducted in this study using 14 chemical transport model results from MICS-Asia III. All models largely underestimated CO concentrations and showed very poor performance in reproducing the observed monthly variations of NH3 concentrations. Potential factors related to such deficiencies are investigated and discussed in this paper.
Yanbing Fan, Cong-Qiang Liu, Linjie Li, Lujie Ren, Hong Ren, Zhimin Zhang, Qinkai Li, Shuang Wang, Wei Hu, Junjun Deng, Libin Wu, Shujun Zhong, Yue Zhao, Chandra Mouli Pavuluri, Xiaodong Li, Xiaole Pan, Yele Sun, Zifa Wang, Kimitaka Kawamura, Zongbo Shi, and Pingqing Fu
Atmos. Chem. Phys., 20, 117–137, https://doi.org/10.5194/acp-20-117-2020, https://doi.org/10.5194/acp-20-117-2020, 2020
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This study provides useful knowledge on the abundance, sources, and formation processes of organic aerosols in the coastal megacity of Tianjin, North China, based on the investigation of the molecular composition, diurnal variation, and winter/summer differences under the influence of land/sea breezes and the Asian summer monsoon.
Yongjoo Choi, Yugo Kanaya, Seung-Myung Park, Atsushi Matsuki, Yasuhiro Sadanaga, Sang-Woo Kim, Itsushi Uno, Xiaole Pan, Meehye Lee, Hyunjae Kim, and Dong Hee Jung
Atmos. Chem. Phys., 20, 83–98, https://doi.org/10.5194/acp-20-83-2020, https://doi.org/10.5194/acp-20-83-2020, 2020
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The relationship between black carbon (BC) and carbon monoxide (CO) can differ by the different structure of fuel consumption. By investigating the representativeness of the BC and CO emission inventory for real-world comparison with reliable observations, this study suggested that accurate CO emissions should be preferentially investigated to enhance the accuracy of the BC emission rate over East Asia.
Danhui Xu, Baozhu Ge, Xueshun Chen, Yele Sun, Nianliang Cheng, Mei Li, Xiaole Pan, Zhiqiang Ma, Yuepeng Pan, and Zifa Wang
Atmos. Chem. Phys., 19, 15569–15581, https://doi.org/10.5194/acp-19-15569-2019, https://doi.org/10.5194/acp-19-15569-2019, 2019
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Wet deposition is one of the most important and efficient removal mechanisms in the evolution of the air pollution. Due to the lack of a localized parameterization scheme and some mechanisms being neglected in theoretical estimations and modeling calculations, below-cloud wet scavenging coefficients (BWSC) have large uncertainties. We compare the BWSCs under the same conditions to perform a multi-method evaluation in order to describe their characteristics.
Hang Liu, Xiaole Pan, Yu Wu, Dawei Wang, Yu Tian, Xiaoyong Liu, Lu Lei, Yele Sun, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 19, 14791–14804, https://doi.org/10.5194/acp-19-14791-2019, https://doi.org/10.5194/acp-19-14791-2019, 2019
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The relationship among the effective density, rBC's coating thickness, and rBC's morphology was investigated. rBC with larger effective density adopted a more regular shape due to more coating thickness. The effective density distribution of ambient rBC was also measured. From the information of effective density, the ambient rBC mainly adopts an irregular shape, which can cause large uncertainties in the rBC's optical properties.
Jie Li, Tatsuya Nagashima, Lei Kong, Baozhu Ge, Kazuyo Yamaji, Joshua S. Fu, Xuemei Wang, Qi Fan, Syuichi Itahashi, Hyo-Jung Lee, Cheol-Hee Kim, Chuan-Yao Lin, Meigen Zhang, Zhining Tao, Mizuo Kajino, Hong Liao, Meng Li, Jung-Hun Woo, Jun-ichi Kurokawa, Zhe Wang, Qizhong Wu, Hajime Akimoto, Gregory R. Carmichael, and Zifa Wang
Atmos. Chem. Phys., 19, 12993–13015, https://doi.org/10.5194/acp-19-12993-2019, https://doi.org/10.5194/acp-19-12993-2019, 2019
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This study evaluated and intercompared 14 CTMs with ozone observations in East Asia, within the framework of the Model Inter-Comparison Study for ASIA Phase III (MICS-Asia III). Potential causes of the discrepancies between model results and observation were investigated by assessing the planetary boundary layer heights, emission fluxes, dry deposition, chemistry and vertical transport among models. Finally, a multi-model estimate of pollution distributions was provided.
Lei Chen, Yi Gao, Meigen Zhang, Joshua S. Fu, Jia Zhu, Hong Liao, Jialin Li, Kan Huang, Baozhu Ge, Xuemei Wang, Yun Fat Lam, Chuan-Yao Lin, Syuichi Itahashi, Tatsuya Nagashima, Mizuo Kajino, Kazuyo Yamaji, Zifa Wang, and Jun-ichi Kurokawa
Atmos. Chem. Phys., 19, 11911–11937, https://doi.org/10.5194/acp-19-11911-2019, https://doi.org/10.5194/acp-19-11911-2019, 2019
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Simulated aerosol concentrations from 14 CTMs within the framework of MICS-Asia III are detailedly evaluated with an extensive set of measurements in East Asia. Similarities and differences among model performances are also analyzed. Although more considerable capacities for reproducing the aerosol concentrations and their variations are shown in current CTMs than those in MICS-Asia II, more efforts are needed to reduce diversities of simulated aerosol concentrations among air quality models.
Qinhao Lin, Yuxiang Yang, Yuzhen Fu, Guohua Zhang, Feng Jiang, Long Peng, Xiufeng Lian, Fengxian Liu, Xinhui Bi, Lei Li, Duohong Chen, Mei Li, Jie Ou, Mingjin Tang, Xinming Wang, Ping'an Peng, and Guoying Sheng
Atmos. Chem. Phys., 19, 10469–10479, https://doi.org/10.5194/acp-19-10469-2019, https://doi.org/10.5194/acp-19-10469-2019, 2019
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The effects of the chemical composition and size of sea-salt-containing particles on their cloud condensation nuclei activity are incompletely understood. Our results showed that submicron sea-salt-containing particles can enrich in small cloud droplets, likely due to change in the chemical composition, while supermicron sea-salt-containing particles tended in the large cloud droplets less affected by chemical composition. This difference might further influence their atmospheric residence time.
Weiqi Xu, Conghui Xie, Eleni Karnezi, Qi Zhang, Junfeng Wang, Spyros N. Pandis, Xinlei Ge, Jingwei Zhang, Junling An, Qingqing Wang, Jian Zhao, Wei Du, Yanmei Qiu, Wei Zhou, Yao He, Ying Li, Jie Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 19, 10205–10216, https://doi.org/10.5194/acp-19-10205-2019, https://doi.org/10.5194/acp-19-10205-2019, 2019
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We present the first aerosol volatility measurements in Beijing in summer using a thermodenuder coupled with aerosol mass spectrometers. Our results showed that organic aerosol (OA) comprised mainly semi-volatile organic compounds in summer, and the freshly oxidized secondary OA was the most volatile component. We also found quite different volatility distributions in black-carbon-containing primary and secondary OA, ambient OA, ambient secondary OA and the WRF-Chem model.
Michael Hollaway, Oliver Wild, Ting Yang, Yele Sun, Weiqi Xu, Conghui Xie, Lisa Whalley, Eloise Slater, Dwayne Heard, and Dantong Liu
Atmos. Chem. Phys., 19, 9699–9714, https://doi.org/10.5194/acp-19-9699-2019, https://doi.org/10.5194/acp-19-9699-2019, 2019
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This study, for the first time, uses combinations of aerosol and lidar data to drive an offline photolysis scheme. Absorbing species are shown to have the greatest impact on photolysis rate constants in the winter and scattering aerosol are shown to dominate responses in the summer. During haze episodes, aerosols are shown to produce a greater impact than cloud cover. The findings demonstrate the potential photochemical impacts of haze pollution in a highly polluted urban environment.
Huiyun Du, Jie Li, Xueshun Chen, Zifa Wang, Yele Sun, Pingqing Fu, Jianjun Li, Jian Gao, and Ying Wei
Atmos. Chem. Phys., 19, 9351–9370, https://doi.org/10.5194/acp-19-9351-2019, https://doi.org/10.5194/acp-19-9351-2019, 2019
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Regional transport and heterogeneous reactions play crucial roles in haze formation. Using a chemical transport model, we found that chemical transformation of SO2 along the transport pathway from source regions to Beijing was the major source of sulfate. Heterogeneous chemistry had a stronger effect under high humidity and high pollution levels. Aerosols underwent aging during transport which altered the aerosol size and the degree of aging.
Tabish Umar Ansari, Oliver Wild, Jie Li, Ting Yang, Weiqi Xu, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 19, 8651–8668, https://doi.org/10.5194/acp-19-8651-2019, https://doi.org/10.5194/acp-19-8651-2019, 2019
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We explore the effectiveness of short-term emission controls on haze events in Beijing in October–November 2014 with high-resolution model studies. The model captures observed hourly variation in key pollutants well, but representation of boundary layer processes remains a key constraint. The controls contributed to improved air quality in early November but would not have been sufficient had the meteorology been less favourable. We quantify the much more stringent controls needed in that case.
Xiaole Pan, Hang Liu, Yu Wu, Yu Tian, Yele Sun, Conghui Xie, Xiaoyong Liu, Tianhai Cheng, and Zifa Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-433, https://doi.org/10.5194/acp-2019-433, 2019
Revised manuscript not accepted
Ying Wei, Xueshun Chen, Huansheng Chen, Jie Li, Zifa Wang, Wenyi Yang, Baozhu Ge, Huiyun Du, Jianqi Hao, Wei Wang, Jianjun Li, Yele Sun, and Huili Huang
Atmos. Chem. Phys., 19, 8269–8296, https://doi.org/10.5194/acp-19-8269-2019, https://doi.org/10.5194/acp-19-8269-2019, 2019
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This study presents a full description and evaluation of a global–regional nested aerosol and atmospheric chemistry model (IAP-AACM). The simulation for 2014 is evaluated against model datasets and a range of observational datasets. The results show that IAP-AACM is within the range of other models, and reproduces both spatial and seasonal variation of trace gases and aerosols over most areas well. In future, we recommend improving the model's ability to capture high spatial variation of PM2.5.
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
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APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Yugo Kanaya, Kazuyuki Miyazaki, Fumikazu Taketani, Takuma Miyakawa, Hisahiro Takashima, Yuichi Komazaki, Xiaole Pan, Saki Kato, Kengo Sudo, Takashi Sekiya, Jun Inoue, Kazutoshi Sato, and Kazuhiro Oshima
Atmos. Chem. Phys., 19, 7233–7254, https://doi.org/10.5194/acp-19-7233-2019, https://doi.org/10.5194/acp-19-7233-2019, 2019
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Ozone and carbon monoxide levels were uniquely observed (for > 10 000 h) over oceans from 67° S to 75° N. Tropospheric chemistry reanalysis v2 reproduced the observed evolution of pollution plumes from continents but underpredicted and overpredicted ozone levels in the Arctic and in the western Pacific equatorial region, respectively. Processes to explain the gaps are proposed, including halogen-mediated destruction in the low latitudes. Our open data set will complement the TOAR data collection.
Linlin Wang, Junkai Liu, Zhiqiu Gao, Yubin Li, Meng Huang, Sihui Fan, Xiaoye Zhang, Yuanjian Yang, Shiguang Miao, Han Zou, Yele Sun, Yong Chen, and Ting Yang
Atmos. Chem. Phys., 19, 6949–6967, https://doi.org/10.5194/acp-19-6949-2019, https://doi.org/10.5194/acp-19-6949-2019, 2019
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Urban boundary layer (UBL) affects the physical and chemical processes of the pollutants, and UBL structure can also be altered by pollutants. This paper presents the interactions between air pollution and the UBL structure by using the field data mainly collected from a 325 m meteorology tower, as well as from a Doppler wind lidar, during a severe heavy pollution event that occurred during 1–4 December 2016 in Beijing.
Dantong Liu, Rutambhara Joshi, Junfeng Wang, Chenjie Yu, James D. Allan, Hugh Coe, Michael J. Flynn, Conghui Xie, James Lee, Freya Squires, Simone Kotthaus, Sue Grimmond, Xinlei Ge, Yele Sun, and Pingqing Fu
Atmos. Chem. Phys., 19, 6749–6769, https://doi.org/10.5194/acp-19-6749-2019, https://doi.org/10.5194/acp-19-6749-2019, 2019
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This study provides source attribution and characterization of BC in the Beijing urban environment in both winter and summer. For the first time, the physically and chemically based source apportionments are compared to evaluate the primary source contribution and secondary processing of BC-containing particles. A method is proposed to isolate the BC from the transportation sector and coal combustion sources.
Xionghui Qiu, Qi Ying, Shuxiao Wang, Lei Duan, Jian Zhao, Jia Xing, Dian Ding, Yele Sun, Baoxian Liu, Aijun Shi, Xiao Yan, Qingcheng Xu, and Jiming Hao
Atmos. Chem. Phys., 19, 6737–6747, https://doi.org/10.5194/acp-19-6737-2019, https://doi.org/10.5194/acp-19-6737-2019, 2019
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Current chemical transport models cannot capture the diurnal and nocturnal variation in atmospheric nitrate, which may be relative to the missing atmospheric chlorine chemistry. In this work, the Community Multiscale Air Quality (CMAQ) model with improved chlorine heterogeneous chemistry is applied to simulate the impact of chlorine chemistry on summer nitrate concentrations in Beijing. The results of this work can improve our understanding of nitrate formation.
Jialin Li, Meigen Zhang, Guiqian Tang, Yele Sun, Fangkun Wu, and Yongfu Xu
Atmos. Chem. Phys., 19, 6481–6495, https://doi.org/10.5194/acp-19-6481-2019, https://doi.org/10.5194/acp-19-6481-2019, 2019
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There are large uncertainties in the sources of secondary organic aerosol (SOA). Simulations of SOA concentrations in China with aqueous SOA formation pathway updated and glyoxal simulation improved reveal that dicarbonyl-derived SOA (AAQ) can explain a significant fraction of the unaccounted SOA sources. The mean AAQ can contribute 60.6 % and 64.5 % to the total concentration of SOA in summer and fall, respectively.
Jingyuan Shao, Qianjie Chen, Yuxuan Wang, Xiao Lu, Pengzhen He, Yele Sun, Viral Shah, Randall V. Martin, Sajeev Philip, Shaojie Song, Yue Zhao, Zhouqing Xie, Lin Zhang, and Becky Alexander
Atmos. Chem. Phys., 19, 6107–6123, https://doi.org/10.5194/acp-19-6107-2019, https://doi.org/10.5194/acp-19-6107-2019, 2019
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Sulfate is a key species contributing to particle formation and growth during wintertime Chinese haze events. This study combines observations and modeling of oxygen isotope signatures in sulfate aerosol to investigate its formation mechanisms, with a focus on heterogeneous production on aerosol surface via H2O2, O3, and NO2 and trace metal catalyzed oxidation. Contributions from different formation pathways are presented.
Zhenying Xu, Mingxu Liu, Minsi Zhang, Yu Song, Shuxiao Wang, Lin Zhang, Tingting Xu, Tiantian Wang, Caiqing Yan, Tian Zhou, Yele Sun, Yuepeng Pan, Min Hu, Mei Zheng, and Tong Zhu
Atmos. Chem. Phys., 19, 5605–5613, https://doi.org/10.5194/acp-19-5605-2019, https://doi.org/10.5194/acp-19-5605-2019, 2019
Kate R. Smith, Peter M. Edwards, Peter D. Ivatt, James D. Lee, Freya Squires, Chengliang Dai, Richard E. Peltier, Mat J. Evans, Yele Sun, and Alastair C. Lewis
Atmos. Meas. Tech., 12, 1325–1336, https://doi.org/10.5194/amt-12-1325-2019, https://doi.org/10.5194/amt-12-1325-2019, 2019
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Clusters of low-cost, low-power atmospheric gas sensors were built into a sensor instrument to monitor NO2 and O3 in Beijing, alongside reference instruments, aiming to improve the reliability of sensor measurements. Clustering identical sensors and using the median sensor signal was used to minimize drift over short and medium timescales. Three different machine learning techniques were used for all the sensor data in an attempt to correct for cross-interferences, which worked to some degree.
Hui Wang, Junmin Lin, Qizhong Wu, Huansheng Chen, Xiao Tang, Zifa Wang, Xueshun Chen, Huaqiong Cheng, and Lanning Wang
Geosci. Model Dev., 12, 749–764, https://doi.org/10.5194/gmd-12-749-2019, https://doi.org/10.5194/gmd-12-749-2019, 2019
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A new framework was designed for the widely used Carbon Bond Mechanism Z (CBM-Z) gas-phase chemical kinetics kernel to adapt the single-instruction, multiple-data (SIMD) technology in next-generation processors like Knights Landing (KNL) to improve their calculation performance. The optimization is aimed at implementing the fine-grain level parallelization of CBM-Z. The test results showed significant acceleration with our optimization on both CPU and KNL platforms.
Shaojie Song, Meng Gao, Weiqi Xu, Yele Sun, Douglas R. Worsnop, John T. Jayne, Yuzhong Zhang, Lei Zhu, Mei Li, Zhen Zhou, Chunlei Cheng, Yibing Lv, Ying Wang, Wei Peng, Xiaobin Xu, Nan Lin, Yuxuan Wang, Shuxiao Wang, J. William Munger, Daniel J. Jacob, and Michael B. McElroy
Atmos. Chem. Phys., 19, 1357–1371, https://doi.org/10.5194/acp-19-1357-2019, https://doi.org/10.5194/acp-19-1357-2019, 2019
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Chemistry responsible for sulfate production in northern China winter haze remains mysterious. We propose a potentially key pathway through the reaction of formaldehyde and sulfur dioxide that has not been accounted for in previous studies. The special atmospheric conditions favor the formation and existence of their complex, hydroxymethanesulfonate (HMS).
Jun Chen, Zhanqing Li, Min Lv, Yuying Wang, Wei Wang, Yingjie Zhang, Haofei Wang, Xing Yan, Yele Sun, and Maureen Cribb
Atmos. Chem. Phys., 19, 1327–1342, https://doi.org/10.5194/acp-19-1327-2019, https://doi.org/10.5194/acp-19-1327-2019, 2019
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The hygroscopic growth function of aerosol particles is derived from Raman lidar, whose dependence on aerosol chemical composition is investigated using data from an aerosol chemical speciation monitor (ACSM) and a hygroscopic tandem differential mobility analyzer (H-TDMA) deployed in China. Two distinct cases were chosen with marked differences in their hygroscopic growth, which was fitted by the Kasten model. The differences were attributed to different amounts of chemical species.
Hajime Akimoto, Tatsuya Nagashima, Jie Li, Joshua S. Fu, Dongsheng Ji, Jiani Tan, and Zifa Wang
Atmos. Chem. Phys., 19, 603–615, https://doi.org/10.5194/acp-19-603-2019, https://doi.org/10.5194/acp-19-603-2019, 2019
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The regional model intercomparison study called MICS-Asia III revealed that substantial discrepancy still exists for surface ozone simulation in East Asia, even though common emissions, meteorological field, and boundary conditions have been used among the models. Three factors have been identified as possible causes of such discrepancy, (1) chemistry sub-models, (2) heterogeneous reactions, and (3) vertical transport parameters, and each component has been discussed.
Junfeng Wang, Dantong Liu, Xinlei Ge, Yangzhou Wu, Fuzhen Shen, Mindong Chen, Jian Zhao, Conghui Xie, Qingqing Wang, Weiqi Xu, Jie Zhang, Jianlin Hu, James Allan, Rutambhara Joshi, Pingqing Fu, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 447–458, https://doi.org/10.5194/acp-19-447-2019, https://doi.org/10.5194/acp-19-447-2019, 2019
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This work is part of the UK-China APHH campaign. We used a laser-only Aerodyne soot particle aerosol mass spectrometer, for the first time, to investigate the concentrations, size distributions and chemical compositions for those ambient submicron aerosol particles only with black carbon as cores. Our findings are valuable to understand the BC properties and processes in the densely populated megacities.
Qiang Huang, Jiubin Chen, Weilin Huang, John R. Reinfelder, Pingqing Fu, Shengliu Yuan, Zhongwei Wang, Wei Yuan, Hongming Cai, Hong Ren, Yele Sun, and Li He
Atmos. Chem. Phys., 19, 315–325, https://doi.org/10.5194/acp-19-315-2019, https://doi.org/10.5194/acp-19-315-2019, 2019
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Although the specific reactions and mechanisms in fine aerosols could not be explicitly determined from this field study, our results provide isotopic evidence that local daily photochemical reduction of divalent Hg is of critical importance to the fate of PM2.5-Hg in urban atmospheres and that, in addition to variation in sources, photochemical reduction appears to be an important process that affects both the particle mass-specific abundance and isotopic composition of PM2.5-Hg.
Xiaole Pan, Baozhu Ge, Zhe Wang, Yu Tian, Hang Liu, Lianfang Wei, Siyao Yue, Itsushi Uno, Hiroshi Kobayashi, Tomoaki Nishizawa, Atsushi Shimizu, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 19, 219–232, https://doi.org/10.5194/acp-19-219-2019, https://doi.org/10.5194/acp-19-219-2019, 2019
Conghui Xie, Weiqi Xu, Junfeng Wang, Qingqing Wang, Dantong Liu, Guiqian Tang, Ping Chen, Wei Du, Jian Zhao, Yingjie Zhang, Wei Zhou, Tingting Han, Qingyun Bian, Jie Li, Pingqing Fu, Zifa Wang, Xinlei Ge, James Allan, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 165–179, https://doi.org/10.5194/acp-19-165-2019, https://doi.org/10.5194/acp-19-165-2019, 2019
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We present the first simultaneous real-time online measurements of aerosol optical properties at ground level and at 260 m on a meteorological tower in urban Beijing in winter. The vertical similarities and differences in scattering and absorption coefficients were characterized. The increases in MAC of BC were mainly associated with the coating materials on rBC. Coal combustion was the dominant source contribution of brown carbon followed by biomass burning and SOA in winter in Beijing.
Yu Tian, Xiaole Pan, Tomoaki Nishizawa, Hiroshi Kobayashi, Itsushi Uno, Xiquan Wang, Atsushi Shimizu, and Zifa Wang
Atmos. Chem. Phys., 18, 18203–18217, https://doi.org/10.5194/acp-18-18203-2018, https://doi.org/10.5194/acp-18-18203-2018, 2018
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East Asia is characterized by severe anthropogenic pollution and dust storms due to fuel consumption and the downwind location of dust sources. We studied the mixing states of dust and pollutants using an optical particle counter equipped with a polarization detection module, providing a deeper understanding of possible mechanisms of aerosols’ morphological change. In Beijing, the heterogeneous processes in the mixture of dust and emitted pollutants have a great influence on smog formation.
Yangyang Zhang, Aohan Tang, Dandan Wang, Qingqing Wang, Katie Benedict, Lin Zhang, Duanyang Liu, Yi Li, Jeffrey L. Collett Jr., Yele Sun, and Xuejun Liu
Atmos. Chem. Phys., 18, 16385–16398, https://doi.org/10.5194/acp-18-16385-2018, https://doi.org/10.5194/acp-18-16385-2018, 2018
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Our study is the first to continually monitor the vertical concentration profile of NH3 in urban Beijing. Weekly concentrations averaged 13.3 ± 4.8 μg m−3. The highest NH3 concentrations were always observed between 32 and 63 m, decreasing toward the surface and toward higher altitudes. Our results demonstrate a NH3 rich atmosphere in urban Beijing, from the ground to at least 320 m. Regional transport from the south (intensive agricultural regions) contributed high NH3 concentrations in Beijing.
Yingjie Zhang, Wei Du, Yuying Wang, Qingqing Wang, Haofei Wang, Haitao Zheng, Fang Zhang, Hongrong Shi, Yuxuan Bian, Yongxiang Han, Pingqing Fu, Francesco Canonaco, André S. H. Prévôt, Tong Zhu, Pucai Wang, Zhanqing Li, and Yele Sun
Atmos. Chem. Phys., 18, 14637–14651, https://doi.org/10.5194/acp-18-14637-2018, https://doi.org/10.5194/acp-18-14637-2018, 2018
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We have a comprehensive characterization of aerosol chemistry and particle growth events at a downwind site of a highly polluted city in the North China Plain. Aerosol particles at the urban downwind site were highly aged and mainly from secondary formation. New particle growth events were also frequently observed on both clean and polluted days. While both sulfate and SOA played important roles in particle growth during clean periods, SOA was more important than sulfate during polluted events.
Lei Liu, Jian Zhang, Liang Xu, Qi Yuan, Dao Huang, Jianmin Chen, Zongbo Shi, Yele Sun, Pingqing Fu, Zifa Wang, Daizhou Zhang, and Weijun Li
Atmos. Chem. Phys., 18, 14681–14693, https://doi.org/10.5194/acp-18-14681-2018, https://doi.org/10.5194/acp-18-14681-2018, 2018
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Using transmission electron microscopy, we studied individual cloud droplet residual and interstitial particles collected in cloud events at Mt. Tai in the polluted North China region. We found that individual cloud droplets were an extremely complicated mixture containing abundant refractory soot (i.e., black carbon), fly ash, and metals. The complicated cloud droplets have not been reported in clean continental or marine air before.
Mingjie Kang, Pingqing Fu, Kimitaka Kawamura, Fan Yang, Hongliang Zhang, Zhengchen Zang, Hong Ren, Lujie Ren, Ye Zhao, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 18, 13947–13967, https://doi.org/10.5194/acp-18-13947-2018, https://doi.org/10.5194/acp-18-13947-2018, 2018
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Molecular characterization and spatial distribution of biogenic primary organic aerosol (POA) and secondary organic aerosol (SOA) in the marine atmosphere are not well known. Here, we analysed the organic molecular composition of marine aerosols collected during a marine cruise in the East China Sea during May–June 2014. Our results suggest that the Asian continent can be a natural emitter of biogenic POA and SOA, which can be transported to the downwind marine atmosphere.
Yuying Wang, Zhanqing Li, Yingjie Zhang, Wei Du, Fang Zhang, Haobo Tan, Hanbing Xu, Tianyi Fan, Xiaoai Jin, Xinxin Fan, Zipeng Dong, Qiuyan Wang, and Yele Sun
Atmos. Chem. Phys., 18, 11739–11752, https://doi.org/10.5194/acp-18-11739-2018, https://doi.org/10.5194/acp-18-11739-2018, 2018
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Very different aerosol hygroscopicities and mixing states were found at these sites in the North China Plain. The PDF for 40–200 nm particles showed the particles were highly aged and internally mixed at Xingtai because of high pollution and strong photochemical reactions. A good proxy for the chemical comical composition (kappa = 0.31) in calculating CCN concentration was found. Importantly, our study investigated the influence of industrial emissions on the aerosol properties.
Wei Zhou, Jian Zhao, Bin Ouyang, Archit Mehra, Weiqi Xu, Yuying Wang, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Qi Chen, Conghui Xie, Qingqing Wang, Junfeng Wang, Wei Du, Yingjie Zhang, Xinlei Ge, Penglin Ye, James D. Lee, Pingqing Fu, Zifa Wang, Douglas Worsnop, Roderic Jones, Carl J. Percival, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 18, 11581–11597, https://doi.org/10.5194/acp-18-11581-2018, https://doi.org/10.5194/acp-18-11581-2018, 2018
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We present measurements of gas-phase N2O5 and ClNO2 by ToF-CIMS during summer in urban Beijing as part of the APHH campaign. High reactivity of N2O5 indicative of active nocturnal chemistry was observed. The lifetime of N2O5 as a function of aerosol surface area and relative humidity was characterized, and N2O5 uptake coefficients were estimated. We also found that the N2O5 loss in this study is mainly attributed to its indirect loss via reactions of NO3 with VOCs and NO.
Chunlei Cheng, Zuzhao Huang, Chak K. Chan, Yangxi Chu, Mei Li, Tao Zhang, Yubo Ou, Duohong Chen, Peng Cheng, Lei Li, Wei Gao, Zhengxu Huang, Bo Huang, Zhong Fu, and Zhen Zhou
Atmos. Chem. Phys., 18, 9147–9159, https://doi.org/10.5194/acp-18-9147-2018, https://doi.org/10.5194/acp-18-9147-2018, 2018
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Particulate amines play an important role for the particle acidity and hygroscopicity. We found amines were internally mixed with sulfate and nitrate at a rural site in the PRD, China, suggesting the formation of aminium sulfate and nitrate salts. The ammonium-poor state of amine particles in summer was associated with the low emission sources of ammonia and a possible contribution of ammonium–amine exchange reactions. Amines could be a buffer for the particle acidity of ammonium-poor particles.
Yele Sun, Weiqi Xu, Qi Zhang, Qi Jiang, Francesco Canonaco, André S. H. Prévôt, Pingqing Fu, Jie Li, John Jayne, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 18, 8469–8489, https://doi.org/10.5194/acp-18-8469-2018, https://doi.org/10.5194/acp-18-8469-2018, 2018
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We present a 2–year analysis of organic aerosol (OA) from highly time–resolved measurements by an aerosol chemical speciation monitor in the megacity of Beijing. The sources of OA were analyzed with the advanced factor analysis of a multilinear engine (ME-2). Our results showed very different seasonal patterns, relative humidity and temperature dependence, and sources regions among different OA factors. The sources and processes of OA factors, and their roles in haze pollution are elucidated.
Xiao-Xiao Zhang, Brenton Sharratt, Lian-You Liu, Zi-Fa Wang, Xiao-Le Pan, Jia-Qiang Lei, Shi-Xin Wu, Shuang-Yan Huang, Yu-Hong Guo, Jie Li, Xiao Tang, Ting Yang, Yu Tian, Xue-Shun Chen, Jian-Qi Hao, Hai-Tao Zheng, Yan-Yan Yang, and Yan-Li Lyu
Atmos. Chem. Phys., 18, 8353–8371, https://doi.org/10.5194/acp-18-8353-2018, https://doi.org/10.5194/acp-18-8353-2018, 2018
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The impact of a strong East Asian dust event during 2–7 May 2017 was quantified and assessed based upon environmental observations, lidar measurements, and satellite products along with simulation techniques. This dust storm impacted a wide area of China and other Asian nations and reached North America within 1 week. Dust storms are a significant contributor to the global dust budget. Asian dust storms such as that observed in early May 2017 may lead to wider climate forcing on a global scale.
Jie Zhang, Sara Lance, Jeffrey M. Freedman, Yele Sun, Brian A. Crandall, Xiuli Wei, and James J. Schwab
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-529, https://doi.org/10.5194/acp-2018-529, 2018
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The impact of fireworks (FW) events on air quality was studied using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and collocated instruments during the Independence Day (July 4) holiday. The Independence Day FW events resulted in significant increases in both organic and inorganic (potassium, sulfate, chloride) chemical components, and the contribution from different aerosol sources was discussed.
Shaojie Song, Meng Gao, Weiqi Xu, Jingyuan Shao, Guoliang Shi, Shuxiao Wang, Yuxuan Wang, Yele Sun, and Michael B. McElroy
Atmos. Chem. Phys., 18, 7423–7438, https://doi.org/10.5194/acp-18-7423-2018, https://doi.org/10.5194/acp-18-7423-2018, 2018
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Severe haze events occur frequently over northern China, especially in winter. Acidity plays a critical role in the formation of secondary PM2.5 and its toxicity. Using field measurements of gases and particles to critically evaluate two thermodynamic models routinely employed to determine particle acidity, we found that China's winter haze particles are generally within a moderately acidic range (pH 4–5) and not highly acidic (0) or neutral (7) as has been previously reported in the literature.
Jingye Ren, Fang Zhang, Yuying Wang, Don Collins, Xinxin Fan, Xiaoai Jin, Weiqi Xu, Yele Sun, Maureen Cribb, and Zhanqing Li
Atmos. Chem. Phys., 18, 6907–6921, https://doi.org/10.5194/acp-18-6907-2018, https://doi.org/10.5194/acp-18-6907-2018, 2018
Meng Gao, Zhiwei Han, Zirui Liu, Meng Li, Jinyuan Xin, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Yafang Cheng, Yuesi Wang, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Jung-Hun Woo, Qiang Zhang, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 18, 4859–4884, https://doi.org/10.5194/acp-18-4859-2018, https://doi.org/10.5194/acp-18-4859-2018, 2018
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Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative and microphysical feedbacks. A comprehensive overview of the MICS-ASIA III Topic 3 study design is presented.
Wei Zhou, Qingqing Wang, Xiujuan Zhao, Weiqi Xu, Chen Chen, Wei Du, Jian Zhao, Francesco Canonaco, André S. H. Prévôt, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 18, 3951–3968, https://doi.org/10.5194/acp-18-3951-2018, https://doi.org/10.5194/acp-18-3951-2018, 2018
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We present a 3-month analysis of submicron aerosols that were measured at 260 m on a meteorological tower in Beijing, China. The sources of organic aerosol (OA) were analyzed by using a multi-linear engine (ME-2). Our results showed significant changes in both primary and secondary OA composition from the non-heating season to the heating season. We also observed a considerable contribution (10–13%) of cooking OA at 260 m and very different OA composition between ground level and 260 m.
Wanyu Zhao, Kimitaka Kawamura, Siyao Yue, Lianfang Wei, Hong Ren, Yu Yan, Mingjie Kang, Linjie Li, Lujie Ren, Senchao Lai, Jie Li, Yele Sun, Zifa Wang, and Pingqing Fu
Atmos. Chem. Phys., 18, 2749–2767, https://doi.org/10.5194/acp-18-2749-2018, https://doi.org/10.5194/acp-18-2749-2018, 2018
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In this paper, we investigate the seasonal trends in concentrations and compound-specific stable carbon isotope ratios of low molecular weight dicarboxylic acids (C2–C12) and related compounds in fine aerosols (PM2.5) in Beijing. Our study demonstrates that, in addition to the production via photo-oxidation, high abundances of diacids and related compounds in Beijing are largely associated with anthropogenic primary emissions such as biomass burning, fossil fuel combustion and plastic burning.
Qingqing Wang, Yele Sun, Weiqi Xu, Wei Du, Libo Zhou, Guiqian Tang, Chen Chen, Xueling Cheng, Xiujuan Zhao, Dongsheng Ji, Tingting Han, Zhe Wang, Jie Li, and Zifa Wang
Atmos. Chem. Phys., 18, 2495–2509, https://doi.org/10.5194/acp-18-2495-2018, https://doi.org/10.5194/acp-18-2495-2018, 2018
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We conducted the first real-time continuous vertical measurements of particle extinction, NO2, and BC from ground level to 260 m during two severe winter haze episodes in urban Beijing, China. Our results show very complex and dynamic vertical profiles that interact closely with boundary layer and meteorological conditions. Further analysis demonstrate that vertical convection, temperature inversion, and local emissions are three major factors affecting the changes in vertical profiles.
Guohua Zhang, Qinhao Lin, Long Peng, Xinhui Bi, Duohong Chen, Mei Li, Lei Li, Fred J. Brechtel, Jianxin Chen, Weijun Yan, Xinming Wang, Ping'an Peng, Guoying Sheng, and Zhen Zhou
Atmos. Chem. Phys., 17, 14975–14985, https://doi.org/10.5194/acp-17-14975-2017, https://doi.org/10.5194/acp-17-14975-2017, 2017
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The mixing state of black carbon (BC)-containing particles and the mass scavenging efficiency of BC in cloud were investigated at a mountain site (1690 m a.s.l.) in southern China. The measured BC-containing particles were internally mixed extensively with sulfate, and thus the number fraction of scavenged BC-containing particles is close to that of all the measured particles. BC-containing particles with higher fractions of organics were scavenged relatively less.
Zheng Fang, Wei Deng, Yanli Zhang, Xiang Ding, Mingjin Tang, Tengyu Liu, Qihou Hu, Ming Zhu, Zhaoyi Wang, Weiqiang Yang, Zhonghui Huang, Wei Song, Xinhui Bi, Jianmin Chen, Yele Sun, Christian George, and Xinming Wang
Atmos. Chem. Phys., 17, 14821–14839, https://doi.org/10.5194/acp-17-14821-2017, https://doi.org/10.5194/acp-17-14821-2017, 2017
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Primary emissions and aging of open straw burning plumes were characterized in ambient dilution conditions in a chamber. Rich in alkenes, the plumes have high O3 formation potential. The emissions of specific particulate and gaseous compounds were less when the straws were fully burned. Organic aerosol (OA) mass increased by a factor of 2–8 with 3–9 h photo-oxidation, yet > 70 % of the mass cannot be explained by the known precursors. OA gained more O- and N-containing compounds during aging.
Yunjiang Zhang, Lili Tang, Philip L. Croteau, Olivier Favez, Yele Sun, Manjula R. Canagaratna, Zhuang Wang, Florian Couvidat, Alexandre Albinet, Hongliang Zhang, Jean Sciare, André S. H. Prévôt, John T. Jayne, and Douglas R. Worsnop
Atmos. Chem. Phys., 17, 14501–14517, https://doi.org/10.5194/acp-17-14501-2017, https://doi.org/10.5194/acp-17-14501-2017, 2017
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We conducted the first field measurements of non-refractory fine aerosols (NR-PM2.5) in a megacity of eastern China using a PM2.5-ACSM along with a PM1-ACSM measurement. Inter-comparisons demonstrated that the NR-PM2.5 components can be characterized. Substantial mass fractions of aerosol species were observed in the size range of 1–2.5 μm, with sulfate and SOA being the two largest contributors. The impacts of aerosol water driven by secondary inorganic aerosols on SOA formation were explored.
Itsushi Uno, Kazuo Osada, Keiya Yumimoto, Zhe Wang, Syuichi Itahashi, Xiaole Pan, Yukari Hara, Yugo Kanaya, Shigekazu Yamamoto, and Thomas Duncan Fairlie
Atmos. Chem. Phys., 17, 14181–14197, https://doi.org/10.5194/acp-17-14181-2017, https://doi.org/10.5194/acp-17-14181-2017, 2017
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We analyzed long-term fine- and coarse-mode nitrate and related aerosols synergetic observations at Fukuoka, Japan. GEOS Chem model including dust and sea-salt acid uptake processes was used to assess the observed seasonal variation, and the impact of long-range transport from the Asian continent. A numerical model reproduced the seasonal variations of fine aerosols. For coarse nitrate, large-scale dust-nitrate outflow from China was confirmed during all dust events between January and June.
Xiaole Pan, Yugo Kanaya, Fumikazu Taketani, Takuma Miyakawa, Satoshi Inomata, Yuichi Komazaki, Hiroshi Tanimoto, Zhe Wang, Itsushi Uno, and Zifa Wang
Atmos. Chem. Phys., 17, 13001–13016, https://doi.org/10.5194/acp-17-13001-2017, https://doi.org/10.5194/acp-17-13001-2017, 2017
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Characteristics of refractory black carbon (rBC) from open biomass burning (OBB) have a great impact on regional pollution and climate, in particular in East Asia. However, experimental study on characteristics of rBC from agricultural residue burning in East China was limited. This study performed laboratory experiments: we found that emission of rBC is highly related to flaming burning, and non-rBC to smoldering burning. Rapid condensation of semi-volatile organics resulted in coated rBC.
Chunlei Cheng, Mei Li, Chak K. Chan, Haijie Tong, Changhong Chen, Duohong Chen, Dui Wu, Lei Li, Cheng Wu, Peng Cheng, Wei Gao, Zhengxu Huang, Xue Li, Zhijuan Zhang, Zhong Fu, Yanru Bi, and Zhen Zhou
Atmos. Chem. Phys., 17, 9519–9533, https://doi.org/10.5194/acp-17-9519-2017, https://doi.org/10.5194/acp-17-9519-2017, 2017
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Oxalic acid is an abundant and ubiquitous constituent in secondary organic aerosol (SOA) and can be an effective tracer for the oxidative processes leading to the formation of SOA. In this work photochemical reactions have a significant contribution to oxalic acid formation in summer, while in winter the formation of oxalic acid is closely associated with the oxidation of organic precursors in the aqueous phase.
Yujiao Zhu, Caiqing Yan, Renyi Zhang, Zifa Wang, Mei Zheng, Huiwang Gao, Yang Gao, and Xiaohong Yao
Atmos. Chem. Phys., 17, 9469–9484, https://doi.org/10.5194/acp-17-9469-2017, https://doi.org/10.5194/acp-17-9469-2017, 2017
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This study reports the distinct effects of street canyons on new particle formation (NPF) under warm or cold ambient temperature conditions because of on-road vehicle emissions; i.e., stronger condensation sinks are responsible for the reduced NPF in the springtime, but efficient nucleation and partitioning of gaseous species contribute to the enhanced NPF in the wintertime. The oxidization of biogenic organics is suggested to play an important role in growing new particles.
Hui Wang, Huansheng Chen, Qizhong Wu, Junmin Lin, Xueshun Chen, Xinwei Xie, Rongrong Wang, Xiao Tang, and Zifa Wang
Geosci. Model Dev., 10, 2891–2904, https://doi.org/10.5194/gmd-10-2891-2017, https://doi.org/10.5194/gmd-10-2891-2017, 2017
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We introduced some methods to port our Global Nested Air Quality Prediction Modeling System (GNAQPMS) model on Intel Knight Landing (KNL). In this paper, we introduced both common and specific methods to accelerate out model better. With the guidance of the resources material on Intel Websites (http://www.intel.com/content/www/us/en/products/processors/xeon-phi.html) and relative books, this paper could be an example for the model developers to take advantage of KNL for their model.
Wei Du, Jian Zhao, Yuying Wang, Yingjie Zhang, Qingqing Wang, Weiqi Xu, Chen Chen, Tingting Han, Fang Zhang, Zhanqing Li, Pingqing Fu, Jie Li, Zifa Wang, and Yele Sun
Atmos. Chem. Phys., 17, 6797–6811, https://doi.org/10.5194/acp-17-6797-2017, https://doi.org/10.5194/acp-17-6797-2017, 2017
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We conducted the first simultaneous measurements of size-resolved particle number concentrations at ground level and 260 m in urban Beijing. The vertical differences strongly depend on particle sizes, with accumulation-mode particles being highly correlated at the two heights. We further demonstrated that regional emission controls have a dominant impact on accumulation-mode particles, while the influences on Aitken particles were much smaller due to the enhanced NPF events.
Ting Yang, Zifa Wang, Wei Zhang, Alex Gbaguidi, Nobuo Sugimoto, Xiquan Wang, Ichiro Matsui, and Yele Sun
Atmos. Chem. Phys., 17, 6215–6225, https://doi.org/10.5194/acp-17-6215-2017, https://doi.org/10.5194/acp-17-6215-2017, 2017
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Predicting air pollution events over megacities requires, notably, continuous and accurate determination of the boundary layer height (BLH). Based on gravity wave theory, a new approach (CRGM) is developed to overcome existing algorithms' weakness in order to accurately reproduce the fluctuations of the BLH under various atmospheric pollution conditions from lidar observation. Comprehensive evaluation highlights strong effectiveness of this new method.
Yuying Wang, Fang Zhang, Zhanqing Li, Haobo Tan, Hanbing Xu, Jingye Ren, Jian Zhao, Wei Du, and Yele Sun
Atmos. Chem. Phys., 17, 5239–5251, https://doi.org/10.5194/acp-17-5239-2017, https://doi.org/10.5194/acp-17-5239-2017, 2017
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A series of strict emission control measures were implemented in Beijing and the surrounding seven provinces to ensure good air quality during the 2015 China Victory Day parade, rendering a unique opportunity to investigate anthropogenic impact of aerosol properties. Submicron aerosol hygroscopicity and volatility were measured during and after the control period. By comparison we found aerosol particles became more hydrophobic and volatile due to the emission control measures.
Jian Zhao, Wei Du, Yingjie Zhang, Qingqing Wang, Chen Chen, Weiqi Xu, Tingting Han, Yuying Wang, Pingqing Fu, Zifa Wang, Zhanqing Li, and Yele Sun
Atmos. Chem. Phys., 17, 3215–3232, https://doi.org/10.5194/acp-17-3215-2017, https://doi.org/10.5194/acp-17-3215-2017, 2017
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We conducted aerosol particle composition measurements at ground level and 260 m with two aerosol mass spectrometers in Beijing during the 2015 China Victory Day parade. Our results showed a stronger impact of emission controls on inorganic aerosol than OA. A larger decrease in more oxidized SOA than the less oxidized one during the control period was also observed. Our results indicate that emission controls and the changes in meteorological conditions have affected SOA formation mechanisms.
Xiao-Xiao Zhang, Brenton Sharratt, Xi Chen, Zi-Fa Wang, Lian-You Liu, Yu-Hong Guo, Jie Li, Huan-Sheng Chen, and Wen-Yi Yang
Atmos. Chem. Phys., 17, 1699–1711, https://doi.org/10.5194/acp-17-1699-2017, https://doi.org/10.5194/acp-17-1699-2017, 2017
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To improve our understanding of the fate and transport of airborne dust, there is a need for long-term records of dust deposition and concentration. This study characterized the spatial and temporal distribution in dust deposition and concentration in central Asia. The occurrence of high dust deposition and concentration suggests this region is a potential contributor to the global dust budget. This work will strengthen our comprehension of aerosol transport in global desertification regions.
Shurui Chen, Liang Xu, Yinxiao Zhang, Bing Chen, Xinfeng Wang, Xiaoye Zhang, Mei Zheng, Jianmin Chen, Wenxing Wang, Yele Sun, Pingqing Fu, Zifa Wang, and Weijun Li
Atmos. Chem. Phys., 17, 1259–1270, https://doi.org/10.5194/acp-17-1259-2017, https://doi.org/10.5194/acp-17-1259-2017, 2017
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Many studies have focused on the unusually severe hazes instead of the more frequent light and moderate hazes (22–63 %) in winter in the North China Plain (NCP). The morphology, mixing state, and size of organic aerosols in the L & M hazes were characterized. We conclude that the direct emissions from residential coal stoves without any pollution controls in rural and urban outskirts contribute large amounts of primary OM particles to the regional L & M hazes in winter in the NCP.
Biwu Chu, Xiao Zhang, Yongchun Liu, Hong He, Yele Sun, Jingkun Jiang, Junhua Li, and Jiming Hao
Atmos. Chem. Phys., 16, 14219–14230, https://doi.org/10.5194/acp-16-14219-2016, https://doi.org/10.5194/acp-16-14219-2016, 2016
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The interactive effects between inorganic and organic species under highly complex pollution conditions remain uncertain and were studied in a smog chamber. This study indicated that the synergistic formation of secondary inorganic and organic aerosol might increase the secondary aerosol load in the atmosphere and contribute haze pollution in eastern China. These synergistic effects were related to the heterogeneous process on aerosol surface and need to be considered in air quality models.
Meng Gao, Gregory R. Carmichael, Pablo E. Saide, Zifeng Lu, Man Yu, David G. Streets, and Zifa Wang
Atmos. Chem. Phys., 16, 11837–11851, https://doi.org/10.5194/acp-16-11837-2016, https://doi.org/10.5194/acp-16-11837-2016, 2016
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The WRF-Chem model was used to examine how the winter PM2.5 concentrations change in response to changes in emissions and meteorology in North China from 1960 to 2010. The discussions in this study indicate that dramatic changes in emissions are the main cause of increasing haze events in North China, and long-term trends in atmospheric circulations maybe another important cause. We also found aerosol feedbacks have been significantly enhanced from 1960 to 2010, due to higher aerosol loadings.
Yugo Kanaya, Xiaole Pan, Takuma Miyakawa, Yuichi Komazaki, Fumikazu Taketani, Itsushi Uno, and Yutaka Kondo
Atmos. Chem. Phys., 16, 10689–10705, https://doi.org/10.5194/acp-16-10689-2016, https://doi.org/10.5194/acp-16-10689-2016, 2016
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Wet removal of atmospheric black carbon particles was quantitatively characterized in terms of accumulated precipitation along a backward trajectory (APT) using long-term observations at Fukue Island, western Japan, receiving Asian continental outflow with variable degrees of influence from precipitation. The emission inventory of BC over East Asia was assessed in terms of the observed BC/CO ratios. Model simulations should be diagnosed with these improved knowledge on the emission and removal.
Xiaole Pan, Itsushi Uno, Yukari Hara, Kazuo Osada, Shigekazu Yamamoto, Zhe Wang, Nobuo Sugimoto, Hiroshi Kobayashi, and Zifa Wang
Atmos. Chem. Phys., 16, 9863–9873, https://doi.org/10.5194/acp-16-9863-2016, https://doi.org/10.5194/acp-16-9863-2016, 2016
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Polarization properties of aerosol particles at a suburban site in the western Japan was studied on the basis of long-term observation and trajectory analysis. This study provides the detailed information on the polarization characteristics of particles from different origins, and proposed a reliable criterion to classify spherical and non-spherical particles. This study introduced a new method to investigate the mixed state of dust particle with anthropogenic pollutant.
Junfeng Wang, Xinlei Ge, Yanfang Chen, Yafei Shen, Qi Zhang, Yele Sun, Jianzhong Xu, Shun Ge, Huan Yu, and Mindong Chen
Atmos. Chem. Phys., 16, 9109–9127, https://doi.org/10.5194/acp-16-9109-2016, https://doi.org/10.5194/acp-16-9109-2016, 2016
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Highly time- and chemically resolved submicron aerosol properties were characterized online for the first time during springtime in Nanjing by using the Aerodyne SP-AMS. Both chemical and size information of black carbon together with other aerosol species were simultaneously determined. An in-depth analysis of the data elucidates the sources and evolution processes of the fine aerosols in the YRD region. Our findings are valuable for air quality remediation in the densely populated regions.
Yele Sun, Wei Du, Pingqing Fu, Qingqing Wang, Jie Li, Xinlei Ge, Qi Zhang, Chunmao Zhu, Lujie Ren, Weiqi Xu, Jian Zhao, Tingting Han, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 16, 8309–8329, https://doi.org/10.5194/acp-16-8309-2016, https://doi.org/10.5194/acp-16-8309-2016, 2016
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We have a comprehensive characterization of the sources, variations and processes of submicron aerosols in Beijing in winter using HR-AMS and GC/MS measurements. The primary sources including traffic, cooking, biomass burning and coal combustion emissions, and secondary components were separated and quantified with PMF. Our results elucidated the important roles of primary emissions, particularly coal combustion, and aqueous-phase processing in the formation of severe air pollution in winter.
Xiao Tang, Jiang Zhu, ZiFa Wang, Alex Gbaguidi, CaiYan Lin, JinYuan Xin, Tao Song, and Bo Hu
Atmos. Chem. Phys., 16, 6395–6405, https://doi.org/10.5194/acp-16-6395-2016, https://doi.org/10.5194/acp-16-6395-2016, 2016
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Chemical data assimilation through adjusting precursor emissions has brought out notable impacts on improving ozone forecasts in previous studies. This paper, from another point of view, investigated in detail the impacts of adjusting nitrogen oxide emissions on the forecasts of nitrogen dioxide through assimilating ozone observations. Limitations of the existing chemical data assimilation methods in a highly nonlinear system were identified and highlighted.
Fang Zhang, Zhanqing Li, Yanan Li, Yele Sun, Zhenzhu Wang, Ping Li, Li Sun, Pucai Wang, Maureen Cribb, Chuanfeng Zhao, Tianyi Fan, Xin Yang, and Qingqing Wang
Atmos. Chem. Phys., 16, 5413–5425, https://doi.org/10.5194/acp-16-5413-2016, https://doi.org/10.5194/acp-16-5413-2016, 2016
Wei Deng, Qihou Hu, Tengyu Liu, Xinming Wang, Yanli Zhang, Xiang Ding, Yele Sun, Xinhui Bi, Jianzhen Yu, Weiqiang Yang, Xinyu Huang, Zhou Zhang, Zhonghui Huang, Quanfu He, A. Mellouki, and Christian George
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-50, https://doi.org/10.5194/acp-2016-50, 2016
Revised manuscript not accepted
M. Gao, G. R. Carmichael, Y. Wang, P. E. Saide, M. Yu, J. Xin, Z. Liu, and Z. Wang
Atmos. Chem. Phys., 16, 1673–1691, https://doi.org/10.5194/acp-16-1673-2016, https://doi.org/10.5194/acp-16-1673-2016, 2016
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The WRF-Chem model was applied to study the 2010 winter haze in North China. Air pollutants outside Beijing contributed about 64.5 % to the PM2.5 levels in Beijing during this haze event, and most of them are from south Hebei, Tianjin city, Shandong and Henan provinces. In addition, aerosol feedback has important impacts on surface temperature, Relative Humidity (RH) and wind speeds, and these meteorological variables affect aerosol distribution and formation in turn.
T. Liu, X. Wang, Q. Hu, W. Deng, Y. Zhang, X. Ding, X. Fu, F. Bernard, Z. Zhang, S. Lü, Q. He, X. Bi, J. Chen, Y. Sun, J. Yu, P. Peng, G. Sheng, and J. Fu
Atmos. Chem. Phys., 16, 675–689, https://doi.org/10.5194/acp-16-675-2016, https://doi.org/10.5194/acp-16-675-2016, 2016
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The formation of SOA and sulfate aerosols from the photooxidation of gasoline vehicle exhaust (GVE) when mixing with SO2 was investigated in a smog chamber. We found that the presence of GVE enhanced the conversion of SO2 to sulfate predominantly through reactions with stabilized Criegee intermediates. On the other hand, the elevated particle acidity enhanced the SOA production from GVE. This study indicated that SO2 and GVE could enhance each other in forming secondary aerosols.
W. Q. Xu, Y. L. Sun, C. Chen, W. Du, T. T. Han, Q. Q. Wang, P. Q. Fu, Z. F. Wang, X. J. Zhao, L. B. Zhou, D. S. Ji, P. C. Wang, and D. R. Worsnop
Atmos. Chem. Phys., 15, 13681–13698, https://doi.org/10.5194/acp-15-13681-2015, https://doi.org/10.5194/acp-15-13681-2015, 2015
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We have investigated the response of aerosol composition, size distributions, and oxidation properties to emission controls during the 2014 Asia- Pacific Economic Cooperation (APEC) summit in Beijing. Our results showed substantial changes of aerosol bulk composition during APEC with the most reductions in secondary aerosols in large accumulation modes, demonstrating that that emission controls over regional scales can substantially reduce secondary particulates.
W. J. Li, S. R. Chen, Y. S. Xu, X. C. Guo, Y. L. Sun, X. Y. Yang, Z. F. Wang, X. D. Zhao, J. M. Chen, and W. X. Wang
Atmos. Chem. Phys., 15, 13365–13376, https://doi.org/10.5194/acp-15-13365-2015, https://doi.org/10.5194/acp-15-13365-2015, 2015
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We found that anthropogenic soot, fly ash, and visible organic particles likely adhere to the surface of secondary inorganic particles larger than 200nm due to coagulation. Biomass burning and coal combustion both constantly contribute to anthropogenic particles in the Qinghai-Tibet Plateau (QTP) background atmosphere. Organic coating and soot on the surface of the aged particles could have different impacts on their hygroscopic and optical properties in the QTP compared to the urban aerosols.
C. Chen, Y. L. Sun, W. Q. Xu, W. Du, L. B. Zhou, T. T. Han, Q. Q. Wang, P. Q. Fu, Z. F. Wang, Z. Q. Gao, Q. Zhang, and D. R. Worsnop
Atmos. Chem. Phys., 15, 12879–12895, https://doi.org/10.5194/acp-15-12879-2015, https://doi.org/10.5194/acp-15-12879-2015, 2015
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A comprehensive characterization of submicron aerosol composition and sources at 260m in urban Beijing during APEC 2014 is presented. Aerosol species were shown to decrease substantially by 40–80% during APEC, whereas the bulk composition was relatively similar to the result of synergetic controls of secondary precursors. Our results elucidated that the good air quality during APEC was the combined result of emission controls and meteorological effects, with the former playing the dominant role.
J. Zheng, J. Zhu, Z. Wang, F. Fang, C. C. Pain, and J. Xiang
Geosci. Model Dev., 8, 3421–3440, https://doi.org/10.5194/gmd-8-3421-2015, https://doi.org/10.5194/gmd-8-3421-2015, 2015
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A new anisotropic hr-adaptive mesh technique has been applied to modelling of multiscale transport phenomena. Over existing air quality models typically based on static-structured grids using a locally nesting technique, the advantage of the anisotropic hr-adaptive model has the ability to adapt the mesh according to the evolving pollutant distribution and flow features. To illustrate its capability, comparisons have been made between the results obtained using adaptive and uniform meshes.
W. Du, Y. L. Sun, Y. S. Xu, Q. Jiang, Q. Q. Wang, W. Yang, F. Wang, Z. P. Bai, X. D. Zhao, and Y. C. Yang
Atmos. Chem. Phys., 15, 10811–10824, https://doi.org/10.5194/acp-15-10811-2015, https://doi.org/10.5194/acp-15-10811-2015, 2015
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A fall field campaign was conducted at a national background site (3295m a.s.l.) over the Tibetan Plateau. The submicron aerosol was dominated by organics (43%) and sulfate (28%). Secondary organic aerosol (SOA) dominated OA (85%), 17% of which being aged biomass burning OA. New particle formation and growth events were frequently observed, with an average particle growth rate of 2.0nm per hour. The important role of organics in particle growth in the Tibetan Plateau was also demonstrated.
H. S. Chen, Z. F. Wang, J. Li, X. Tang, B. Z. Ge, X. L. Wu, O. Wild, and G. R. Carmichael
Geosci. Model Dev., 8, 2857–2876, https://doi.org/10.5194/gmd-8-2857-2015, https://doi.org/10.5194/gmd-8-2857-2015, 2015
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A new global nested atmospheric mercury transport model was developed and introduced. Model performance was found significantly better in North America and Europe than in East Asia. Nested simulation has been conducted in East Asia and shows improved skill at capturing the high spatial variability of Hg concentrations and deposition. The trans-boundary transport of Chinese primary anthropogenic mercury emissions was quantified for the first time.
Y. L. Sun, Z. F. Wang, W. Du, Q. Zhang, Q. Q. Wang, P. Q. Fu, X. L. Pan, J. Li, J. Jayne, and D. R. Worsnop
Atmos. Chem. Phys., 15, 10149–10165, https://doi.org/10.5194/acp-15-10149-2015, https://doi.org/10.5194/acp-15-10149-2015, 2015
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We conducted the first long-term real-time measurement of submicron aerosol composition in Beijing using an ACSM for 1 year. The seasonal variations of mass concentrations and chemical composition of submicron aerosol were investigated in detail, and the meteorological effects on aerosol chemistry, particularly temperature and relative humidity, were elucidated. Finally, the potential source areas of aerosol species during four seasons were identified.
Y. R. Yang, X. G. Liu, Y. Qu, J. L. An, R. Jiang, Y. H. Zhang, Y. L. Sun, Z. J. Wu, F. Zhang, W. Q. Xu, and Q. X. Ma
Atmos. Chem. Phys., 15, 8165–8178, https://doi.org/10.5194/acp-15-8165-2015, https://doi.org/10.5194/acp-15-8165-2015, 2015
X. Pan, Y. Kanaya, H. Tanimoto, S. Inomata, Z. Wang, S. Kudo, and I. Uno
Atmos. Chem. Phys., 15, 6101–6111, https://doi.org/10.5194/acp-15-6101-2015, https://doi.org/10.5194/acp-15-6101-2015, 2015
Q. Jiang, Y. L. Sun, Z. Wang, and Y. Yin
Atmos. Chem. Phys., 15, 6023–6034, https://doi.org/10.5194/acp-15-6023-2015, https://doi.org/10.5194/acp-15-6023-2015, 2015
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Aerosol composition and sources during the Chinese spring festival are characterized in detail. The roles of fireworks and secondary aerosol in fine particle pollution were elucidated. We observed large reductions of primary species, whereas changes of secondary aerosol during the holiday period were minor. This has significant implications; reducing primary emissions on a local scale during severe haze episodes might have a limited effect on improving air quality in megacities.
Y. J. Zhang, L. L. Tang, Z. Wang, H. X. Yu, Y. L. Sun, D. Liu, W. Qin, F. Canonaco, A. S. H. Prévôt, H. L. Zhang, and H. C. Zhou
Atmos. Chem. Phys., 15, 1331–1349, https://doi.org/10.5194/acp-15-1331-2015, https://doi.org/10.5194/acp-15-1331-2015, 2015
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The chemical composition, sources, and evolution processes of PM1 were investigated with an Aerodyne ACSM during harvest seasons in the Yangtze River delta, China. Two biomass burning organic aerosol (BBOA) factors derived from PMF model were assessed. The oxidized BBOA contributes ~80% of the total BBOA loadings in the BB plumes. Evidence that BBOA may be oxidized to more aged and less volatile organics during the aging process was suggested.
Q. Z. Wu, W. S. Xu, A. J. Shi, Y. T. Li, X. J. Zhao, Z. F. Wang, J. X. Li, and L. N. Wang
Geosci. Model Dev., 7, 2243–2259, https://doi.org/10.5194/gmd-7-2243-2014, https://doi.org/10.5194/gmd-7-2243-2014, 2014
Y. Kanaya, H. Akimoto, Z.-F. Wang, P. Pochanart, K. Kawamura, Y. Liu, J. Li, Y. Komazaki, H. Irie, X.-L. Pan, F. Taketani, K. Yamaji, H. Tanimoto, S. Inomata, S. Kato, J. Suthawaree, K. Okuzawa, G. Wang, S. G. Aggarwal, P. Q. Fu, T. Wang, J. Gao, Y. Wang, and G. Zhuang
Atmos. Chem. Phys., 13, 8265–8283, https://doi.org/10.5194/acp-13-8265-2013, https://doi.org/10.5194/acp-13-8265-2013, 2013
K. Kawamura, E. Tachibana, K. Okuzawa, S. G. Aggarwal, Y. Kanaya, and Z. F. Wang
Atmos. Chem. Phys., 13, 8285–8302, https://doi.org/10.5194/acp-13-8285-2013, https://doi.org/10.5194/acp-13-8285-2013, 2013
Y. Zhang, K. Sartelet, S. Zhu, W. Wang, S.-Y. Wu, X. Zhang, K. Wang, P. Tran, C. Seigneur, and Z.-F. Wang
Atmos. Chem. Phys., 13, 6845–6875, https://doi.org/10.5194/acp-13-6845-2013, https://doi.org/10.5194/acp-13-6845-2013, 2013
N. He, K. Kawamura, K. Okuzawa, Y. Kanaya, and Z. F. Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-16699-2013, https://doi.org/10.5194/acpd-13-16699-2013, 2013
Revised manuscript not accepted
K. Kawamura, K. Okuzawa, S. G. Aggarwal, H. Irie, Y. Kanaya, and Z. Wang
Atmos. Chem. Phys., 13, 5369–5380, https://doi.org/10.5194/acp-13-5369-2013, https://doi.org/10.5194/acp-13-5369-2013, 2013
Y. L. Sun, Z. F. Wang, P. Q. Fu, T. Yang, Q. Jiang, H. B. Dong, J. Li, and J. J. Jia
Atmos. Chem. Phys., 13, 4577–4592, https://doi.org/10.5194/acp-13-4577-2013, https://doi.org/10.5194/acp-13-4577-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Source-dependent optical properties and molecular characteristics of atmospheric brown carbon
Multi-year black carbon observations and modeling close to the largest gas flaring and wildfire regions in the Western Siberian Arctic
Pollution affects Arabian and Saharan dust optical properties in the eastern Mediterranean
Phase matrix characterization of long-range-transported Saharan dust using multiwavelength-polarized polar imaging nephelometry
Measurement report: The influence of particle number size distribution and hygroscopicity on the microphysical properties of cloud droplets at a mountain site
Measurement report: Long-term assessment of primary and secondary organic aerosols in the Shanghai megacity throughout China's Clean Air actions since 2010
The evolution of aerosol mixing state derived from a field campaign in Beijing: implications for particle aging timescales in urban atmospheres
Field Observations Reveal Substantially Higher Scattering Refractive Index in Secondary Versus Primary Organic Aerosols
Measurement report: Size-resolved particle effective density measured by an AAC-SMPS and implications for chemical composition
Locally emitted fungal spores serve as high temperature ice nucleating particles in the European sub-Arctic
Measurement report: Aircraft observations of aerosol and microphysical quantities of stratocumulus in autumn over Guangxi Province, China – daylight variation, vertical distribution, and aerosol–cloud interactions
Hygroscopic aerosols amplify longwave downward radiation in the Arctic
Measurement report: Aerosol and cloud nuclei properties along the Central and Northern Great Barrier Reef: Impact of continental emissions
Measurement report: Optical and structural properties of atmospheric water-soluble organic carbon in China – insights from multi-site spectroscopic measurements
Measurement report: The variation properties of aerosol hygroscopic growth related to chemical composition during new particle formation days in a coastal city of Southeast China
In situ vertical observations of the layered structure of air pollution in a continental high-latitude urban boundary layer during winter
Size-resolved hygroscopicity and volatility properties of ambient urban aerosol particles measured by a volatility hygroscopicity tandem differential mobility analyzer system in Beijing
Terrestrial runoff is an important source of biological ice-nucleating particles in Arctic marine systems
Characterization of aerosol over the eastern Mediterranean by polarization-sensitive Raman lidar measurements during A-LIFE – aerosol type classification and type separation
Aerosol spectral optical properties in the Paris urban area and its peri-urban and forested surroundings during summer 2022 from ACROSS surface observations
Measurement report: An investigation of the spatiotemporal variability in aerosols in the mountainous terrain of the upper Colorado River basin using SAIL-Net
Contributions of the synoptic meteorology to the seasonal cloud condensation nuclei cycle over the Southern Ocean
Measurement report: Cloud condensation nuclei (CCN) activity in the South China Sea from shipborne observations during the summer and winter of 2021 – seasonal variation and anthropogenic influence
Biomass burning smoke transport and radiative impact over the city of Sao Paulo: An extreme event case study
Differential characterization of air ions in boreal forest of Finland and megacity of eastern China
On-road vehicle emission measurements show a significant reduction of black carbon and nitrogen oxides emissions in Euro6c and 6d diesel-powered cars
Bioaerosols as indicators of central Arctic ice nucleating particle sources
Measurement report: A comparative analysis of an intensive incursion of fluorescing African dust particles over Puerto Rico and another over Spain
Measurement report: Analysis of aerosol optical depth variation at Zhongshan Station in Antarctica
External particle mixing influences hygroscopicity in a sub-urban area
Long-term observations of black carbon and carbon monoxide in the Poker Flat Research Range, central Alaska, with a focus on forest wildfire emissions
Origin, size distribution and hygroscopic properties of marine aerosols in the south-western Indian Ocean: report of 6 campaigns of shipborne observations
High ice-nucleating particle concentrations associated with Arctic haze in springtime cold-air outbreaks
CCN estimations at a high-altitude remote site: role of organic aerosol variability and hygroscopicity
Aerosol hygroscopicity over the South-East Atlantic Ocean during the biomass burning season: Part II – Influence of burning conditions on CCN hygroscopicity
Aerosol hygroscopicity over the southeast Atlantic Ocean during the biomass burning season – Part 1: From the perspective of scattering enhancement
Spatial, temporal, and meteorological impact of the 26 February 2023 dust storm: increase in particulate matter concentrations across New Mexico and West Texas
Large spatiotemporal variability in aerosol properties over central Argentina during the CACTI field campaign
Microphysical properties of refractory black carbon aerosols for different air masses at a central European background site
Quantification and characterization of primary biological aerosol particles and microbes aerosolized from Baltic seawater
Brownness of organics in anthropogenic biomass burning aerosols over South Asia
Strong influence of Black Carbon on aerosol optical properties in Central Amazonia during the fire season
Source apportionment of particle number size distribution at the street canyon and urban background sites
Long-range transport of coarse mineral dust: an evaluation of the Met Office Unified Model against aircraft observations
Extreme Saharan dust events expand northward over the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 episodes
Atmospheric black carbon in the metropolitan area of La Paz and El Alto, Bolivia: concentration levels and emission sources
Changing optical properties of black carbon and brown carbon aerosols during long-range transport from the Indo-Gangetic Plain to the equatorial Indian Ocean
Aerosol size distribution properties associated with cold-air outbreaks in the Norwegian Arctic
Ice-nucleating particles active below −24 °C in a Finnish boreal forest and their relationship to bioaerosols
Measurements of particle emissions of an A350-941 burning 100 % sustainable aviation fuels in cruise
Jinghao Zhai, Yin Zhang, Pengfei Liu, Yujie Zhang, Antai Zhang, Yaling Zeng, Baohua Cai, Jingyi Zhang, Chunbo Xing, Honglong Yang, Xiaofei Wang, Jianhuai Ye, Chen Wang, Tzung-May Fu, Lei Zhu, Huizhong Shen, Shu Tao, and Xin Yang
Atmos. Chem. Phys., 25, 7959–7972, https://doi.org/10.5194/acp-25-7959-2025, https://doi.org/10.5194/acp-25-7959-2025, 2025
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Our study shows that the optical properties of brown carbon depend on its source. Brown carbon from ozone pollution had the weakest light absorption but the strongest wavelength dependence, while biomass burning brown carbon showed the strongest absorption and the weakest wavelength dependence. Nitrogen-containing organic carbon compounds were identified as key light absorbers. These results improve understanding of brown carbon sources and help refine climate models.
Olga B. Popovicheva, Marina A. Chichaeva, Nikolaos Evangeliou, Sabine Eckhardt, Evangelia Diapouli, and Nikolay S. Kasimov
Atmos. Chem. Phys., 25, 7719–7739, https://doi.org/10.5194/acp-25-7719-2025, https://doi.org/10.5194/acp-25-7719-2025, 2025
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High-quality measurements of light-absorbing carbon were performed at the polar aerosol station "Island Bely” (Western Siberian Arctic) from 2019 to 2022. The maximum light absorption coefficients were seen in summer due to gas flaring, which is the most significant source in the region. However, the increasing Siberian wildfires had a special share in carbon contribution at this high Arctic station, with a persistent smoke layer extending over the whole troposphere in summer.
Marilena Teri, Josef Gasteiger, Katharina Heimerl, Maximilian Dollner, Manuel Schöberl, Petra Seibert, Anne Tipka, Thomas Müller, Sudharaj Aryasree, Konrad Kandler, and Bernadett Weinzierl
Atmos. Chem. Phys., 25, 6633–6662, https://doi.org/10.5194/acp-25-6633-2025, https://doi.org/10.5194/acp-25-6633-2025, 2025
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The A-LIFE aircraft field experiment was carried out in the eastern Mediterranean in 2017. Using A-LIFE data, we studied the change in mineral dust optical properties due to mixing with anthropogenic aerosols. We found that increasing pollution affects dust optical properties, which has implications for identifying dust events and understanding their climate effects. We also show that optical properties of Saharan and Arabian dust are similar when comparing cases with equal pollution content.
Elena Bazo, Daniel Pérez-Ramírez, Antonio Valenzuela, J. Vanderlei Martins, Gloria Titos, Alberto Cazorla, Fernando Rejano, Diego Patrón, Arlett Díaz-Zurita, Francisco José García-Izquierdo, David Fuertes, Lucas Alados-Arboledas, and Francisco José Olmo
Atmos. Chem. Phys., 25, 6325–6352, https://doi.org/10.5194/acp-25-6325-2025, https://doi.org/10.5194/acp-25-6325-2025, 2025
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This works analyzes the aerosol scattering phase function for transported Saharan dust to the city of Granada – located in southwestern Europe. We use the novel technique polar imaging nephelometry that helps to determine the phase functions using a CMOS camera. The capability of measuring with polarized light helps to infer new properties about the mixture of Saharan dust particles with those of anthropogenic origin.
Xiaojing Shen, Quan Liu, Junying Sun, Wanlin Kong, Qianli Ma, Bing Qi, Lujie Han, Yangmei Zhang, Linlin Liang, Lei Liu, Shuo Liu, Xinyao Hu, Jiayuan Lu, Aoyuan Yu, Huizheng Che, and Xiaoye Zhang
Atmos. Chem. Phys., 25, 5711–5725, https://doi.org/10.5194/acp-25-5711-2025, https://doi.org/10.5194/acp-25-5711-2025, 2025
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In this work, an automatic switched inlet system was developed and employed to investigate the aerosols and cloud droplets at a mountain site with frequent cloud processes. It showed different characteristics of cloud residual and interstitial particles. Stronger particle hygroscopicity reduced liquid water content and smaller cloud droplet diameters. This investigation contributes to understanding aerosol–cloud interactions by assessing the impact of aerosol particles on cloud microphysics.
Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, and Jianlin Hu
Atmos. Chem. Phys., 25, 5355–5369, https://doi.org/10.5194/acp-25-5355-2025, https://doi.org/10.5194/acp-25-5355-2025, 2025
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This study presents long-term measurements and comprehensive analysis of carbonaceous aerosols in fine particles in Shanghai. We further estimated primary and secondary carbon levels, examining their temporal variations on interannual, monthly, seasonal, and diurnal scales. Through rigorous statistical analysis and correlation studies with meteorological parameters and pollutant concentrations, the origins, formation mechanisms, and spatial distribution patterns of secondary organic carbon were elucidated.
Jieyao Liu, Fang Zhang, Jingye Ren, Lu Chen, Anran Zhang, Zhe Wang, Songjian Zou, Honghao Xu, and Xingyan Yue
Atmos. Chem. Phys., 25, 5075–5086, https://doi.org/10.5194/acp-25-5075-2025, https://doi.org/10.5194/acp-25-5075-2025, 2025
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Particle mixing states and aging timescales are important for the evaluation of aerosol climate effects, but they are poorly parameterized in current models. We unravel the evolution of real-time mixing states and the aging timescale of size-resolved particles based on field measurements in urban Beijing. This study provides an observational basis for accurately parameterizing the aging timescale of aerosol particles in climate models.
Junlin Shen, Li Liu, Fengling Yuan, Biao Luo, Hongqing Qiao, Miaomiao Zhai, Gang Zhao, Hanbing Xu, Fei Li, Yu Zou, Tao Deng, Xuejiao Deng, and Ye Kuang
EGUsphere, https://doi.org/10.5194/egusphere-2025-1410, https://doi.org/10.5194/egusphere-2025-1410, 2025
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This study provides direct observational evidence that secondary organic aerosols have substantially higher real refractive indices than primary organic aerosols, challenging current model assumptions and offering recommended values that improve the accuracy of aerosol radiative effect simulations.
Yao Song, Jing Wei, Wenlong Zhao, Jinmei Ding, Xiangyu Pei, Fei Zhang, Zhengning Xu, Ruifang Shi, Ya Wei, Lu Zhang, Lingling Jin, and Zhibin Wang
Atmos. Chem. Phys., 25, 4755–4766, https://doi.org/10.5194/acp-25-4755-2025, https://doi.org/10.5194/acp-25-4755-2025, 2025
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This study investigates the size-resolved effective density (ρeff) of aerosol particles in Hangzhou using a tandem aerodynamic aerosol classifier and scanning mobility particle sizer system. The ρeff values ranged from 1.47 to 1.63 g cm-3, increasing with particle diameter. The relationship between ρeff and the particle diameter varies due to differences in the chemical composition of the particles. A new method to derive the size-resolved chemical composition of particles from ρeff is proposed.
Jürgen Gratzl, Alexander Böhmländer, Sanna Pätsi, Clara-E. Pogner, Markus Gorfer, David Brus, Konstantino Matthaios Doulgeris, Florian Wieland, Eija Asmi, Annika Saarto, Ottmar Möhler, Dominik Stolzenburg, and Hinrich Grothe
EGUsphere, https://doi.org/10.5194/egusphere-2025-1599, https://doi.org/10.5194/egusphere-2025-1599, 2025
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We studied particles in the air over one year in the Finnish sub-Arctic to understand how biological particles affect ice formation in clouds. We found that fungal spores are the main contributors to ice formation at warmer temperatures. These particles are released locally and vary with weather. Our results also show that we know very little about which fungi can form ice in the atmosphere, highlighting a major gap in our understanding of how nature influences weather and climate.
Sihan Liu, Honglei Wang, Delong Zhao, Wei Zhou, Yuanmou Du, Zhengguo Zhang, Peng Cheng, Tianliang Zhao, Yue Ke, Zihao Wu, and Mengyu Huang
Atmos. Chem. Phys., 25, 4151–4165, https://doi.org/10.5194/acp-25-4151-2025, https://doi.org/10.5194/acp-25-4151-2025, 2025
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To understand the effect of aerosols on the vertical distribution of stratocumulus microphysical quantities in southwest China, the daily variation characteristics and formation mechanism of the vertical profiles of stratocumulus microphysical characteristics in this region were described using the data of nine cloud-crossing aircraft observations over Guangxi from 10 October to 3 November 2020.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
Atmos. Chem. Phys., 25, 3889–3904, https://doi.org/10.5194/acp-25-3889-2025, https://doi.org/10.5194/acp-25-3889-2025, 2025
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Our study explores how certain aerosols, like sea salt, affect infrared heat radiation in the Arctic, potentially speeding up warming. We used advanced technology to measure aerosol composition and found that these particles grow with humidity, significantly increasing their heat-trapping effect in the infrared region, especially in winter. Our findings suggest these aerosols could be a key factor in Arctic warming, emphasizing the importance of understanding aerosols for climate prediction.
E. Johanna Horchler, Joel Alroe, Luke Harrison, Luke Cravigan, Daniel P. Harrison, and Zoran D. Ristovski
EGUsphere, https://doi.org/10.5194/egusphere-2025-465, https://doi.org/10.5194/egusphere-2025-465, 2025
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Aerosols play a role in global climate by interacting with incoming solar radiation and by taking up water vapour from the atmosphere to form clouds. Enhancing local-scale cloud cover can reduce sea surface temperatures. Coral bleaching events increased in the Great Barrier Reef (GBR) as sea surface temperatures rise. Our study found that the number of aerosols and the cloud forming ability over the GBR increased if the aerosols were transported from inland Australia rather than the ocean.
Haibiao Chen, Caiqing Yan, Liubin Huang, Lin Du, Yang Yue, Xinfeng Wang, Qingcai Chen, Mingjie Xie, Junwen Liu, Fengwen Wang, Shuhong Fang, Qiaoyun Yang, Hongya Niu, Mei Zheng, Yan Wu, and Likun Xue
Atmos. Chem. Phys., 25, 3647–3667, https://doi.org/10.5194/acp-25-3647-2025, https://doi.org/10.5194/acp-25-3647-2025, 2025
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A comprehensive understanding of the optical properties of brown carbon (BrC) is essential to accurately assess its climatic effects. Based on multi-site spectroscopic measurements, this study demonstrated the significant spatial heterogeneity in the optical and structural properties of water-soluble organic carbon (WSOC) in different regions of China and revealed factors affecting WSOC light absorption and the relationship between fluorophores and light absorption of WSOC.
Lingjun Li, Mengren Li, Xiaolong Fan, Yuping Chen, Ziyi Lin, Anqi Hou, Siqing Zhang, Ronghua Zheng, and Jinsheng Chen
Atmos. Chem. Phys., 25, 3669–3685, https://doi.org/10.5194/acp-25-3669-2025, https://doi.org/10.5194/acp-25-3669-2025, 2025
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Here, we show differences and variations in the aerosol scattering hygroscopic growth factor (f(RH)) between new particle formation (NPF) and non-NPF days and the effect of aerosol chemical compositions on f(RH) in Xiamen with in situ observations. The findings are helpful for the further understanding of aerosol hygroscopicity in a coastal city and the use of hygroscopic growth factors in models of air quality and climate change.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
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This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Aoyuan Yu, Xiaojing Shen, Qianli Ma, Jiayuan Lu, Xinyao Hu, Yangmei Zhang, Quan Liu, Linlin Liang, Lei Liu, Shuo Liu, Hongfei Tong, Huizheng Che, Xiaoye Zhang, and Junying Sun
Atmos. Chem. Phys., 25, 3389–3412, https://doi.org/10.5194/acp-25-3389-2025, https://doi.org/10.5194/acp-25-3389-2025, 2025
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In this work, we utilized a volatility hygroscopicity tandem differential mobility analyzer (VH-TDMA) to investigate, for the first time, the hygroscopicity and volatility of submicron aerosols, as well as their hygroscopicity after heating, in urban Beijing during the autumn of 2023. We analyzed the size-resolved characteristics of hygroscopicity and volatility, the relationship between hygroscopic and volatile properties, and the hygroscopicity of heated submicron aerosols.
Corina Wieber, Lasse Z. Jensen, Leendert Vergeynst, Lorenz Meire, Thomas Juul-Pedersen, Kai Finster, and Tina Šantl-Temkiv
Atmos. Chem. Phys., 25, 3327–3346, https://doi.org/10.5194/acp-25-3327-2025, https://doi.org/10.5194/acp-25-3327-2025, 2025
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The Arctic region is subject to profound changes due to a warming climate. Ice-nucleating particles (INPs) in the seawater can get transported to the atmosphere and impact cloud formation. However, the sources of characteristics of INPs in the marine areas are poorly understood. We investigated the INPs in seawater from Greenlandic fjords and identified a seasonal variability, with highly active INPs originating from terrestrial sources such as glacial and soil runoff.
Silke Groß, Volker Freudenthaler, Moritz Haarig, Albert Ansmann, Carlos Toledano, David Mateos, Petra Seibert, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Josef Gasteiger, Maximilian Dollner, Anne Tipka, Manuel Schöberl, Marilena Teri, and Bernadett Weinzierl
Atmos. Chem. Phys., 25, 3191–3211, https://doi.org/10.5194/acp-25-3191-2025, https://doi.org/10.5194/acp-25-3191-2025, 2025
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Aerosols contribute to the largest uncertainties in climate change predictions. The eastern Mediterranean is a hotspot for aerosols with natural and anthropogenic contributions. We present lidar measurements performed during A-LIFE (Absorbing aerosol layers in a changing climate: aging, lifetime and dynamics) to characterize aerosols and aerosol mixtures. We extend current lidar classification and separation schemes and compare them to classification schemes using different methods.
Ludovico Di Antonio, Claudia Di Biagio, Paola Formenti, Aline Gratien, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Patrice Coll, Barbara D'Anna, Joel F. de Brito, David O. De Haan, Juliette R. Dignum, Shravan Deshmukh, Olivier Favez, Pierre-Marie Flaud, Cecile Gaimoz, Lelia N. Hawkins, Julien Kammer, Brigitte Language, Franck Maisonneuve, Griša Močnik, Emilie Perraudin, Jean-Eudes Petit, Prodip Acharja, Laurent Poulain, Pauline Pouyes, Eva Drew Pronovost, Véronique Riffault, Kanuri I. Roundtree, Marwa Shahin, Guillaume Siour, Eric Villenave, Pascal Zapf, Gilles Foret, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 25, 3161–3189, https://doi.org/10.5194/acp-25-3161-2025, https://doi.org/10.5194/acp-25-3161-2025, 2025
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The spectral complex refractive index (CRI) and single scattering albedo were retrieved from submicron aerosol measurements at three sites within the greater Paris area during the ACROSS field campaign (June–July 2022). Measurements revealed urban emission impact on surrounding areas. CRI full period averages at 520 nm were 1.41 – 0.037i (urban), 1.52 – 0.038i (peri-urban), and 1.50 – 0.025i (rural). Organic aerosols dominated the aerosol mass and contributed up to 22 % of absorption at 370 nm.
Leah D. Gibson, Ezra J. T. Levin, Ethan Emerson, Nick Good, Anna Hodshire, Gavin McMeeking, Kate Patterson, Bryan Rainwater, Tom Ramin, and Ben Swanson
Atmos. Chem. Phys., 25, 2745–2762, https://doi.org/10.5194/acp-25-2745-2025, https://doi.org/10.5194/acp-25-2745-2025, 2025
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From fall 2021 to summer 2023, SAIL-Net, a network of six aerosol measurement nodes, was deployed in the East River watershed (Colorado, USA) to study aerosol variability across space and time in mountainous terrain. We found that aerosol variability is influenced by elevation differences, with the most representative site in the region changing seasonally, suggesting aerosol spatial variability also varies seasonally. This work offers a blueprint for future studies in other mountainous regions.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
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Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Hengjia Ou, Mingfu Cai, Yongyun Zhang, Xue Ni, Baoling Liang, Qibin Sun, Shixin Mai, Cuizhi Sun, Shengzhen Zhou, Haichao Wang, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 25, 2495–2513, https://doi.org/10.5194/acp-25-2495-2025, https://doi.org/10.5194/acp-25-2495-2025, 2025
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Two shipborne observations in the South China Sea (SCS) in summer and winter 2021 were conducted. Our study found aerosol hygroscopicity is higher in the SCS in summer than winter, with significant influences from various terrestrial air masses. Aerosol size distribution had a stronger effect on activation ratio than aerosol hygroscopicity in summer and vice versa in winter. Our study provides valuable information to enhance our understanding of cloud condensation nuclei activities in the SCS.
Jorge Rosas Santana, Gabriela Lima da Silva, Marcia Akemi Yamasoe, and Nilton Èvora do Rosario
EGUsphere, https://doi.org/10.5194/egusphere-2025-9, https://doi.org/10.5194/egusphere-2025-9, 2025
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This study examines a rare event in São Paulo, Brazil, where wildfire smoke from South America mixed with clouds, causing midday darkness on 19 August 2019. Satellite data, surface measurements, and air mass modeling tracked the smoke from fires in Brazil, Bolivia, and Paraguay, transported to São Paulo within two days. The smoke-cloud interaction reduced surface irradiance to zero for 40 minutes and increased radiative efficiency by 7 %, highlighting impacts on air quality, energy, and climate.
Tinghan Zhang, Ximeng Qi, Janne Lampilahti, Liangduo Chen, Xuguang Chi, Wei Nie, Xin Huang, Zehao Zou, Wei Du, Tom Kokkonen, Tuukka Petäjä, Katrianne Lehtipalo, Veli-Matti Kerminen, Aijun Ding, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2024-3370, https://doi.org/10.5194/egusphere-2024-3370, 2025
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By comparing air ions at two “flagship” sites —the SMEAR II site in the boreal forest of Finland and the SORPES site in a megacity in eastern China—we characterized ion concentrations and their roles in new particle formation (NPF) across contrasting environments. The ion-induced fraction was much higher in clean areas. However, earlier activation of charged particles and high ion-induced fraction during quiet NPF at SORPES imply a non-negligible role for ion-induced NPF in polluted areas.
Irena Ježek Brecelj, Asta Gregorič, Lucijan Zgonik, Tjaša Rutar, Matic Ivančič, Balint Alfoldy, Griša Močnik, and Martin Rigler
EGUsphere, https://doi.org/10.5194/egusphere-2024-3553, https://doi.org/10.5194/egusphere-2024-3553, 2025
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Following a major car industry scandal involving diesel emissions tests, Europe introduced new testing procedures. However, concerns remained about their effectiveness. Our independent study examined real-world vehicle emissions and revealed encouraging findings: modern diesel cars perform as well as, or even better than, gasoline cars in terms of nitrogen oxides emissions. We found the same pattern for soot particles, challenging common perceptions about diesel's environmental impact.
Kevin R. Barry, Thomas C. J. Hill, Sonia M. Kreidenweis, Paul J. DeMott, Yutaka Tobo, and Jessie M. Creamean
EGUsphere, https://doi.org/10.5194/egusphere-2025-128, https://doi.org/10.5194/egusphere-2025-128, 2025
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The Arctic is changing rapidly, and we sought to better understand how their clouds may change in the future through quantifying the natural cloud seeding particles over a year and uncover what they are made of. We wanted to determine their likely sources through concurrent DNA sequencing of airborne bacteria and fungi and found a persistent mixture of local and longer-range sources at all times.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
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Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Lijing Chen, Lei Zhang, Yong She, Zhaoliang Zeng, Yu Zheng, Biao Tian, Wenqian Zhang, Zhaohui Liu, Huizheng Che, and Minghu Ding
Atmos. Chem. Phys., 25, 727–739, https://doi.org/10.5194/acp-25-727-2025, https://doi.org/10.5194/acp-25-727-2025, 2025
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Aerosol optical depth (AOD) at Zhongshan Station varies seasonally, with lower values in summer and higher values in winter. Winter and spring AOD increases due to reduced fine-mode particles, while summer and autumn increases are linked to particle growth. Diurnal AOD variation correlates positively with temperature but negatively with wind speed and humidity. Backward trajectories show that aerosols on high-AOD (low-AOD) days primarily originate from the ocean (interior Antarctica).
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
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Aerosol hygroscopicity has been investigated at a sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Takeshi Kinase, Fumikazu Taketani, Masayuki Takigawa, Chunmao Zhu, Yongwon Kim, Petr Mordovskoi, and Yugo Kanaya
Atmos. Chem. Phys., 25, 143–156, https://doi.org/10.5194/acp-25-143-2025, https://doi.org/10.5194/acp-25-143-2025, 2025
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Boreal forest wildfires in interior Alaska represent an important black carbon (BC) source for the Arctic and surrounding regions. We observed BC and carbon monoxide (CO) concentrations in the Poker Flat Research Range since 2016 and found a positive correlation between the observed BC / ∆CO ratio and fire radiative power (FRP) observed in Alaska and Canada. Our finding suggests the BC emission factor and/or inventory could be potentially improved by using FRP.
Meredith Dournaux, Pierre Tulet, Joris Pianezze, Jérome Brioude, Jean-Marc Metzger, and Melilotus Thyssen
EGUsphere, https://doi.org/10.5194/egusphere-2024-3747, https://doi.org/10.5194/egusphere-2024-3747, 2025
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Aerosol measurements collected during six oceanographic campaigns carried out in 2021 and 2023 in the southwest Indian Ocean are presented and analyzed in this paper. The results highlight a large variability in the aerosol concentration, size and water vapor affinity depending on in-situ conditions and air mass transport over the ocean. Marine aerosol chemical composition is highly variable over this region, and should be considered to better study their impacts on regional weather and climate.
Erin N. Raif, Sarah L. Barr, Mark D. Tarn, James B. McQuaid, Martin I. Daily, Steven J. Abel, Paul A. Barrett, Keith N. Bower, Paul R. Field, Kenneth S. Carslaw, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 14045–14072, https://doi.org/10.5194/acp-24-14045-2024, https://doi.org/10.5194/acp-24-14045-2024, 2024
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Ice-nucleating particles (INPs) allow ice to form in clouds at temperatures warmer than −35°C. We measured INP concentrations over the Norwegian and Barents seas in weather events where cold air is ejected from the Arctic. These concentrations were among the highest measured in the Arctic. It is likely that the INPs were transported to the Arctic from distant regions. These results show it is important to consider hemispheric-scale INP processes to understand INP concentrations in the Arctic.
Fernando Rejano, Andrea Casans, Marta Via, Juan Andrés Casquero-Vera, Sonia Castillo, Hassan Lyamani, Alberto Cazorla, Elisabeth Andrews, Daniel Pérez-Ramírez, Andrés Alastuey, Francisco Javier Gómez-Moreno, Lucas Alados-Arboledas, Francisco José Olmo, and Gloria Titos
Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, https://doi.org/10.5194/acp-24-13865-2024, 2024
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This study provides valuable insights to improve cloud condensation nuclei (CCN) estimations at a high-altitude remote site which is influenced by nearby urban pollution. Understanding the factors that affect CCN estimations is essential to improve the CCN data coverage worldwide and assess aerosol–cloud interactions on a global scale. This is crucial for improving climate models, since aerosol–cloud interactions are the most important source of uncertainty in climate projections.
Haochi Che, Lu Zhang, Michal Segal-Rozenhaimer, Caroline Dang, Paquita Zuidema, and Arthur J. Sedlacek III
EGUsphere, https://doi.org/10.5194/egusphere-2024-3304, https://doi.org/10.5194/egusphere-2024-3304, 2024
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We investigated how biomass burning (BB) affects cloud formation in the southeast Atlantic. We found that aerosol hygroscopicity, which influences cloud droplet formation, varied monthly and differed significantly between 2016 and 2017, due to changes in sulfate aerosols. These changes were driven by BB burning conditions, which were likely influenced by meteorological factors. This study highlights the important role of BB in shaping aerosol properties and clouds in the region.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, Paola Formenti, and Steven G. Howell
Atmos. Chem. Phys., 24, 13849–13864, https://doi.org/10.5194/acp-24-13849-2024, https://doi.org/10.5194/acp-24-13849-2024, 2024
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Using airborne measurements over the southeast Atlantic Ocean, we examined how much moisture aerosols take up during Africa’s biomass burning season. Our study revealed the important role of organic aerosols and introduced a predictive model for moisture uptake, accounting for organics, sulfate, and black carbon, summarizing results from various campaigns. These findings improve our understanding of aerosol–moisture interactions and their radiative effects in this climatically critical region.
Mary C. Robinson, Kaitlin Schueth, and Karin Ardon-Dryer
Atmos. Chem. Phys., 24, 13733–13750, https://doi.org/10.5194/acp-24-13733-2024, https://doi.org/10.5194/acp-24-13733-2024, 2024
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On 26 February 2023, New Mexico and West Texas were impacted by a severe dust storm. To analyze this storm, 28 meteorological stations and 19 PM2.5 and PM10 stations were used. Dust particles were in the air for 16 h, and dust storm conditions lasted for up to 120 min. Hourly PM2.5 and PM10 concentrations were up to 518 and 9983 µg m−3, respectively. For Lubbock, Texas, the maximum PM2.5 concentrations were the highest ever recorded.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa Emmons
Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, https://doi.org/10.5194/acp-24-13477-2024, 2024
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Aerosol property measurements recently collected on the ground and by a research aircraft in central Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable data set needed to evaluate and improve model predictions of aerosols in a traditionally data-sparse region of South America.
Yifan Yang, Thomas Müller, Laurent Poulain, Samira Atabakhsh, Bruna A. Holanda, Jens Voigtländer, Shubhi Arora, and Mira L. Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2024-3539, https://doi.org/10.5194/egusphere-2024-3539, 2024
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Black carbon (BC) is the major atmospheric aerosol that can absorb light and influence climate. We measured the physical properties of BC at a background site in Germany. In summer, BC particles were smaller and the mixture with other atmospheric components occurred during the daytime. In winter, emissions from residential heating significantly influenced BC's properties. Understanding these characteristics of BC can help improve aerosol optics simulation accuracy.
Julika Zinke, Gabriel Pereira Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 13413–13428, https://doi.org/10.5194/acp-24-13413-2024, https://doi.org/10.5194/acp-24-13413-2024, 2024
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Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber during two ship-based campaigns to collect and measure these aerosols. We found that microbes were enriched in air compared to seawater. Bacterial diversity was analysed using DNA sequencing. Our methods provided consistent estimates of microbial emission fluxes, aligning with previous studies.
Chimurkar Navinya, Taveen Singh Kapoor, Gupta Anurag, Chandra Venkataraman, Harish C. Phuleria, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 24, 13285–13297, https://doi.org/10.5194/acp-24-13285-2024, https://doi.org/10.5194/acp-24-13285-2024, 2024
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Brown carbon (BrC) aerosols show an order-of-magnitude variation in their light absorption strength. Our understanding of BrC from real-world biomass burning remains limited, complicating the determination of its radiative impact. Our study reports absorption properties of BrC emitted from four major biomass burning sources using field measurements in India. It develops an absorption parameterization for BrC and examines the spatial variability in BrC's absorption strength across India.
Rafael Stern, Joel F. de Brito, Samara Carbone, Luciana Varanda Rizzo, Jonathan Daniel Muller, and Paulo Artaxo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3339, https://doi.org/10.5194/egusphere-2024-3339, 2024
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Our work reveals the impact of forest fires on climate. We found that particles related to direct emissions from fires, beyond the well-known effect of absorbing light and thus heating the atmosphere, are also very efficient in scattering light, which causes an atmospheric cooling effect. In our remote study site, most of the particles presented a different chemical composition then particles directly emitted by the fires, but those were the main responsible for total light extinction.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Natalie G. Ratcliffe, Claire L. Ryder, Nicolas Bellouin, Stephanie Woodward, Anthony Jones, Ben Johnson, Lisa-Maria Wieland, Maximilian Dollner, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Chem. Phys., 24, 12161–12181, https://doi.org/10.5194/acp-24-12161-2024, https://doi.org/10.5194/acp-24-12161-2024, 2024
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Large mineral dust particles are more abundant in the atmosphere than expected and have different impacts on the environment than small particles, which are better represented in climate models. We use aircraft measurements to assess a climate model representation of large-dust transport. We find that the model underestimates the amount of large dust at all stages of transport and that fast removal of the large particles increases this underestimation with distance from the Sahara.
Sergio Rodríguez and Jessica López-Darias
Atmos. Chem. Phys., 24, 12031–12053, https://doi.org/10.5194/acp-24-12031-2024, https://doi.org/10.5194/acp-24-12031-2024, 2024
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Extreme Saharan dust events expanded northward to the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 events. These episodes are caused by low-to-high dipole meteorology during hemispheric anomalies characterized by subtropical anticyclones shifting to higher latitudes, anomalous low pressures beyond the tropics and amplified Rossby waves. Extreme dust events occur in a paradoxical context of a multidecadal decrease in dust emissions, a topic that requires further investigation.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
Krishnakant Budhavant, Mohanan Remani Manoj, Hari Ram Chandrika Rajendran Nair, Samuel Mwaniki Gaita, Henry Holmstrand, Abdus Salam, Ahmed Muslim, Sreedharan Krishnakumari Satheesh, and Örjan Gustafsson
Atmos. Chem. Phys., 24, 11911–11925, https://doi.org/10.5194/acp-24-11911-2024, https://doi.org/10.5194/acp-24-11911-2024, 2024
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The South Asian Pollution Experiment 2018 used access to three strategically located receptor observatories. Observational constraints revealed opposing trends in the mass absorption cross sections of black carbon (BC MAC) and brown carbon (BrC MAC) during long-range transport. Models estimating the climate effects of BC aerosols may have underestimated the ambient BC MAC over distant receptor areas, leading to discrepancies in aerosol absorption predicted by observation-constrained models.
Abigail S. Williams, Jeramy L. Dedrick, Lynn M. Russell, Florian Tornow, Israel Silber, Ann M. Fridlind, Benjamin Swanson, Paul J. DeMott, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 24, 11791–11805, https://doi.org/10.5194/acp-24-11791-2024, https://doi.org/10.5194/acp-24-11791-2024, 2024
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The measured aerosol size distribution modes reveal distinct properties characteristic of cold-air outbreaks in the Norwegian Arctic. We find higher sea spray number concentrations, smaller Hoppel minima, lower effective supersaturations, and accumulation-mode particle scavenging during cold-air outbreaks. These results advance our understanding of cold-air outbreak aerosol–cloud interactions in order to improve their accurate representation in models.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Rebecca Dischl, Daniel Sauer, Christiane Voigt, Theresa Harlaß, Felicitas Sakellariou, Raphael Märkl, Ulrich Schumann, Monika Scheibe, Stefan Kaufmann, Anke Roiger, Andreas Dörnbrack, Charles Renard, Maxime Gauthier, Peter Swann, Paul Madden, Darren Luff, Mark Johnson, Denise Ahrens, Reetu Sallinen, Tobias Schripp, Georg Eckel, Uwe Bauder, and Patrick Le Clercq
Atmos. Chem. Phys., 24, 11255–11273, https://doi.org/10.5194/acp-24-11255-2024, https://doi.org/10.5194/acp-24-11255-2024, 2024
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In-flight measurements of aircraft emissions burning 100 % sustainable aviation fuel (SAF) show reduced particle number concentrations up to 41 % compared to conventional jet fuel. Particle emissions are dependent on engine power setting, flight altitude, and fuel composition. Engine models show a good correlation with measurement results. Future increased prevalence of SAF can positively influence the climate impact of aviation.
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Short summary
We characterized the impacts of emission controls on particle mixing state and density during the Beijing Olympic Winter Games using a SPAMS in tandem with a DMA and an AAC. OC and sulfate-containing particles increased, while those from primary emissions decreased. The effective particle densities increased and varied largely for different particles, highlighting the impacts of aging and formation processes on the changes of particle density and mixing state.
We characterized the impacts of emission controls on particle mixing state and density during...
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