In:
Nature Communications, Springer Science and Business Media LLC, Vol. 13, No. 1 ( 2022-02-17)
Kurzfassung:
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 (Cl 2 ), 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 Cl 2 (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 Cl 2 production. The high Cl 2 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.
Materialart:
Online-Ressource
ISSN:
2041-1723
DOI:
10.1038/s41467-022-28383-9
Sprache:
Englisch
Verlag:
Springer Science and Business Media LLC
Publikationsdatum:
2022
ZDB Id:
2553671-0
