TY - JOUR
T1 - Atmospheric gaseous hydrochloric and hydrobromic acid in urban Beijing, China
T2 - Detection, source identification and potential atmospheric impacts
AU - Fan, Xiaolong
AU - Cai, Jing
AU - Yan, Chao
AU - Zhao, Jian
AU - Guo, Yishuo
AU - Li, Chang
AU - Dällenbach, Kaspar R.
AU - Zheng, Feixue
AU - Lin, Zhuohui
AU - Chu, Biwu
AU - Wang, Yonghong
AU - Dada, Lubna
AU - Zha, Qiaozhi
AU - Du, Wei
AU - Kontkanen, Jenni
AU - Kurtén, Theo
AU - Iyer, Siddhart
AU - Kujansuu, Joni T.
AU - Petäjä, Tuukka
AU - Worsnop, Douglas R.
AU - Kerminen, Veli Matti
AU - Liu, Yongchun
AU - Bianchi, Federico
AU - Tham, Yee Jun
AU - Yao, Lei
AU - Kulmala, Markku
N1 - Funding Information:
Acknowledgements. The work is supported by the Academy of Finland (ACCC Flagship, grant no. 337549, Center of Excellence in Atmospheric Sciences, project no. 307331, and PROFI3 funding, 311932), the European Research Council via ATM-GTP (grant no. 742206), CHAPAs (grant no. 850614) and the EMME-CARE project, which has received funding from the European Union’s Horizon 2020 Research and Innovation.
Funding Information:
Financial support. This research has been supported by the
Funding Information:
Academy of Finland (ACCC Flagship, grant no. 337549, Center of Excellence in Atmospheric Sciences, project no. 307331, and PROFI3 funding, 311932) and the European Research Council via ATM-GTP (grant no. 742206) and CHAPAs (grant no. 850614).
Publisher Copyright:
© 2021 Atmospheric Chemistry and Physics. All rights reserved.
PY - 2021
Y1 - 2021
N2 - Gaseous hydrochloric (HCl) and hydrobromic acid (HBr) are vital halogen species that play essential roles in tropospheric physicochemical processes. Yet, the majority of the current studies on these halogen species were conducted in marine or coastal areas. Detection and source identification of HCl and HBr in inland urban areas remain scarce, thus limiting the full understanding of halogen chemistry and potential atmospheric impacts in the environments with limited influence from the marine sources. Here, both gaseous HCl and HBr were concurrently measured in urban Beijing, China, during winter and early spring of 2019. We observed significant HCl and HBr concentrations ranging from a minimum value at 1gg108 molecules cm-3 (4gppt) and 4gg107 molecules cm-3 (1gppt) up to 6gg109 molecules cm-3 (222gppt) and 1gg109 molecules cm-3 (37gppt), respectively. The HCl and HBr concentrations are enhanced along with the increase of atmospheric temperature, UVB and levels of gaseous HNO3. Based on the air mass analysis and high correlations of HCl and HBr with the burning indicators (HCN and HCNO), gaseous HCl and HBr are found to be related to anthropogenic burning aerosols. The gas-particle partitioning may also play a dominant role in the elevated daytime HCl and HBr. During the daytime, the reactions of HCl and HBr with OH radicals lead to significant production of atomic Cl and Br, up to 2gg104 molecules cm-3gs-1 and 8gg104 moleculesgcm-3gs-1, respectively. The production rate of atomic Br (via HBrg+gOH) is 2-3 times higher than that of atomic Cl (via HClg+gOH), highlighting the potential importance of bromine chemistry in the urban area. On polluted days, the production rates of atomic Cl and Br are faster than those on clean days. Furthermore, our observations of elevated HCl and HBr may suggest an important recycling pathway of halogen species in inland megacities and may provide a plausible explanation for the widespread halogen chemistry, which could affect the atmospheric oxidation in China.
AB - Gaseous hydrochloric (HCl) and hydrobromic acid (HBr) are vital halogen species that play essential roles in tropospheric physicochemical processes. Yet, the majority of the current studies on these halogen species were conducted in marine or coastal areas. Detection and source identification of HCl and HBr in inland urban areas remain scarce, thus limiting the full understanding of halogen chemistry and potential atmospheric impacts in the environments with limited influence from the marine sources. Here, both gaseous HCl and HBr were concurrently measured in urban Beijing, China, during winter and early spring of 2019. We observed significant HCl and HBr concentrations ranging from a minimum value at 1gg108 molecules cm-3 (4gppt) and 4gg107 molecules cm-3 (1gppt) up to 6gg109 molecules cm-3 (222gppt) and 1gg109 molecules cm-3 (37gppt), respectively. The HCl and HBr concentrations are enhanced along with the increase of atmospheric temperature, UVB and levels of gaseous HNO3. Based on the air mass analysis and high correlations of HCl and HBr with the burning indicators (HCN and HCNO), gaseous HCl and HBr are found to be related to anthropogenic burning aerosols. The gas-particle partitioning may also play a dominant role in the elevated daytime HCl and HBr. During the daytime, the reactions of HCl and HBr with OH radicals lead to significant production of atomic Cl and Br, up to 2gg104 molecules cm-3gs-1 and 8gg104 moleculesgcm-3gs-1, respectively. The production rate of atomic Br (via HBrg+gOH) is 2-3 times higher than that of atomic Cl (via HClg+gOH), highlighting the potential importance of bromine chemistry in the urban area. On polluted days, the production rates of atomic Cl and Br are faster than those on clean days. Furthermore, our observations of elevated HCl and HBr may suggest an important recycling pathway of halogen species in inland megacities and may provide a plausible explanation for the widespread halogen chemistry, which could affect the atmospheric oxidation in China.
U2 - 10.5194/acp-21-11437-2021
DO - 10.5194/acp-21-11437-2021
M3 - Article
AN - SCOPUS:85112116499
SN - 1680-7316
VL - 21
SP - 11437
EP - 11452
JO - Atmospheric Chemistry and Physics
JF - Atmospheric Chemistry and Physics
IS - 14
ER -
