Photodissociation of particulate nitrate as a source of daytime tropospheric Cl2 - Archive ouverte HAL Access content directly
Journal Articles Nature Communications Year : 2022

Photodissociation of particulate nitrate as a source of daytime tropospheric Cl2

Weihao Wang
  • Function : Author
Men Xia
  • Function : Author
Min Cai
  • Function : Author
Qinyi Li
Christian Mark Salvador
  • Function : Author
Chiho Lau
  • Function : Author
Xiaopu Lyu
  • Function : Author
Chun Nan Poon
  • Function : Author
Yujing Mu
Mattias Hallquist
Alfonso Saiz-Lopez
Hai Guo
  • Function : Author
Chuan Yu
  • Function : Author
Jianing Dai
  • Function : Author
Yanan Wang
  • Function : Author
Xinke Wang
  • Function : Author
Alfred Yu
  • Function : Author
Kenneth Leung
  • Function : Author
Shuncheng Lee

Abstract

Abstract Chlorine atoms (Cl) are highly reactive and can strongly influence the abundances of climate and air quality-relevant trace gases. Despite extensive research on molecular chlorine (Cl2 ), a Cl precursor, in the polar atmosphere, its sources in other regions are still poorly understood. Here we report the daytime Cl 2 concentrations of up to 1 ppbv observed in a coastal area of Hong Kong, revealing a large daytime source of Cl2 (2.7 pptv s−1 at noon). Field and laboratory experiments indicate that photodissociation of particulate nitrate by sunlight under acidic conditions (pH < 3.0) can activate chloride and account for the observed daytime Cl2 production. The high Cl2 concentrations significantly increased atmospheric oxidation. Given the ubiquitous existence of chloride, nitrate, and acidic aerosols, we propose that nitrate photolysis is a significant daytime chlorine source globally. This so far unaccounted for source of chlorine can have substantial impacts on atmospheric chemistry.
Fichier principal
Vignette du fichier
s41467-022-28383-9.pdf (1.95 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

hal-03579273 , version 1 (05-10-2022)

Identifiers

Cite

Xiang Peng, Tao Wang, Weihao Wang, A. Ravishankara, Christian George, et al.. Photodissociation of particulate nitrate as a source of daytime tropospheric Cl2. Nature Communications, 2022, 13 (1), pp.939. ⟨10.1038/s41467-022-28383-9⟩. ⟨hal-03579273⟩
41 View
23 Download

Altmetric

Share

Gmail Facebook X LinkedIn More