title: Measurements of nitrous acid (HONO) in urban area of Shanghai, China.
abstract: Nitrous acid (HONO), as a precursor of the hydroxyl radical (OH), plays an important role in the photochemistry of the troposphere, especially in the polluted urban atmosphere. A field campaign was conducted to measure atmospheric HONO concentration and that of other pollutants (such as NO2 and particle mass concentration) in the autumn of 2009 at Shanghai urban areas. HONO mixing ratios were simultaneously measured by three different techniques: long path absorption photometer (LOPAP), differential optical absorption spectroscopy (DOAS) and chemical ionization mass spectrometer (CIMS). The measurements showed that the mixing ratios of HONO were highly variable and depended strongly on meteorological parameters. The HONO levels ranged from 0.5 to 7 ppb with maximum values during early morning and minimum levels during late afternoon. The three instruments reproduced consistent diurnal pattern of HONO concentrations with higher concentration during the night compared to the daylight hours. Comparison of HONOLOPAP/HONOCIMS ratios during daytime and nighttime periods exhibited a non-systematic disagreement of 0.93 and 1.16, respectively. This would indicate different chemical compositions of sampled air for the LOPAP and the CIMS instruments during daytime and nighttime periods, which have possibly affected measurements. Mean HONO concentration reported by LOPAP was 33 % higher than by DOAS on the whole period with no significant difference between daytime and nighttime periods. This revealed a systematic deviation from both instruments. The present data provides complementary information of HONO ambient levels in the atmosphere of Shanghai urban areas.
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France.
authors.forename: François
authors.initials: F
authors.lastname: Bernard
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Cazaunau
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France.
authors.forename: Benoît
authors.initials: B
authors.lastname: Grosselin
authors.affiliation: Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan Tyndall Centre, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200433, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Department of Atmospheric Sciences, Texas A&M University, College Station, TX, 77840, USA.|School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France.|Research Center for Eco-environmental of Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.affiliation: Research Center for Eco-environmental of Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan Tyndall Centre, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200433, China.
authors.forename: Xingnan
authors.initials: X
authors.lastname: Ye
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Daële
authors.affiliation: Research Center for Eco-environmental of Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Mu
authors.affiliation: Department of Atmospheric Sciences, Texas A&M University, College Station, TX, 77840, USA.
authors.forename: Renyi
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan Tyndall Centre, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200433, China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Chen
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, Centre National de la Recherche Scientifique/OSUC, 45071, Orléans cedex 02, France. mellouki@cnrs-orleans.fr.|Environment Research Institute/School of Environmental Science & Engineering, Shandong University, Shandong, 250100, China. mellouki@cnrs-orleans.fr.
authors.forename: Abdelwahid
authors.initials: A
authors.lastname: Mellouki
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere / Q000737:chemistry*; D002681:China; D017665:Hydroxyl Radical; D009608:Nitrous Acid / Q000032:analysis*; D013057:Spectrum Analysis
chemical_list: D000393:Air Pollutants; D017665:Hydroxyl Radical; D009608:Nitrous Acid
keywords: Ambient levels; DOAS; ID-CIMS; Intercomparison; LOPAP; Nitrous acid; Shanghai urban area