Evidence of Aerosols as a Media for Rapid Daytime HONO Production over China

Liu, Z; Wang, Y; Costabile, F; Amoroso, A; Zhao, C; Huey, LG; Stickel, R; Liao, J; Zhu, T

HERO ID

2533783

Reference Type

Journal Article

Year

2014

Language

English

PMID

25401515

HERO ID 2533783
In Press No
Year 2014
Title Evidence of Aerosols as a Media for Rapid Daytime HONO Production over China
Authors Liu, Z; Wang, Y; Costabile, F; Amoroso, A; Zhao, C; Huey, LG; Stickel, R; Liao, J; Zhu, T
Journal Environmental Science & Technology
Volume 48
Issue 24
Page Numbers 14386-14391
Abstract Current knowledge of daytime HONO sources remains incomplete. A large missing daytime HONO source has been found in many places around the world, including polluted regions in China. Conventional understanding and recent studies attributed this missing source mainly to ground surface processes or gas-phase chemistry, while assuming aerosols to be an insignificant media for HONO production. We analyze in situ observations of HONO and its precursors at an urban site in Beijing, China, and report an apparent dependence of the missing HONO source strength on aerosol surface area and solar ultraviolet radiation. Based on extensive correlation analysis and process-modeling, we propose that the rapid daytime HONO production in Beijing can be explained by enhanced hydrolytic disproportionation of NO2 on aqueous aerosol surfaces due to catalysis by dicarboxylic acid anions. The combination of high abundance of NO2, aromatic hydrocarbons, and aerosols over broad regions in China likely leads to elevated HONO levels, rapid OH production, and enhanced oxidizing capacity on a regional basis. Our findings call for attention to aerosols as a media for daytime heterogeneous HONO production in polluted regions like Beijing. This study also highlights the complex and uncertain heterogeneous chemistry in China, which merits future efforts of reconciling regional modeling and laboratory experiments, in order to understand and mitigate the regional particulate and O3 pollutions over China.
Doi 10.1021/es504163z
Pmid 25401515
Wosid WOS:000346686100040
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English