title: An Atmospheric Constraint on the NO2 Dependence of Daytime Near-Surface Nitrous Acid (HONO).
abstract: Recent observations suggest a large and unknown daytime source of nitrous acid (HONO) to the atmosphere. Multiple mechanisms have been proposed, many of which involve chemistry that reduces nitrogen dioxide (NO2) on some time scale. To examine the NO2 dependence of the daytime HONO source, we compare weekday and weekend measurements of NO2 and HONO in two U.S. cities. We find that daytime HONO does not increase proportionally to increases in same-day NO2, i.e., the local NO2 concentration at that time and several hours earlier. We discuss various published HONO formation pathways in the context of this constraint.
authors.affiliation: Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Sally E
authors.initials: SE
authors.lastname: Pusede
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Trevor C
authors.initials: TC
authors.lastname: VandenBoer
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Jennifer G
authors.initials: JG
authors.lastname: Murphy
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Milos Z
authors.initials: MZ
authors.lastname: Markovic
authors.affiliation: Earth Systems Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA) , Boulder, Colorado 80305, United States.|Cooperative Institute for Research in Environmental Science, University of Colorado Boulder , Boulder, Colorado 80309, United States.
authors.forename: Cora J
authors.initials: CJ
authors.lastname: Young
authors.affiliation: Earth Systems Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA) , Boulder, Colorado 80305, United States.|Cooperative Institute for Research in Environmental Science, University of Colorado Boulder , Boulder, Colorado 80309, United States.
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Veres
authors.affiliation: Earth Systems Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA) , Boulder, Colorado 80305, United States.
authors.forename: James M
authors.initials: JM
authors.lastname: Roberts
authors.affiliation: Earth Systems Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA) , Boulder, Colorado 80305, United States.|Cooperative Institute for Research in Environmental Science, University of Colorado Boulder , Boulder, Colorado 80309, United States.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Washenfelder
authors.affiliation: Earth Systems Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA) , Boulder, Colorado 80305, United States.|Department of Chemistry and Biochemistry, University of Colorado Boulder , Boulder, Colorado 80309, United States.
authors.forename: Steven S
authors.initials: SS
authors.lastname: Brown
authors.affiliation: Air Resources Laboratory, National Oceanic and Atmospheric Administration , College Park, Maryland 20740, United States.
authors.forename: Xinrong
authors.initials: X
authors.lastname: Ren
authors.affiliation: Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles , Los Angeles, California 90095, United States.
authors.forename: Catalina
authors.initials: C
authors.lastname: Tsai
authors.affiliation: Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles , Los Angeles, California 90095, United States.
authors.forename: Jochen
authors.initials: J
authors.lastname: Stutz
authors.affiliation: Department of Meteorology, Pennsylvania State University , University Park, Pennsylvania 16802, United States.
authors.forename: William H
authors.initials: WH
authors.lastname: Brune
authors.affiliation: Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Eleanor C
authors.initials: EC
authors.lastname: Browne
authors.affiliation: Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Wooldridge
authors.affiliation: Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Ashley R
authors.initials: AR
authors.lastname: Graham
authors.affiliation: Department of Environmental Science, Policy, and Management, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Robin
authors.initials: R
authors.lastname: Weber
authors.affiliation: Department of Environmental Science, Policy, and Management, University of California, Berkeley , Berkeley, California 94720, United States.|Department of Civil and Environmental Engineering, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Allen H
authors.initials: AH
authors.lastname: Goldstein
authors.affiliation: School of Public and Environmental Affairs, Indiana University , Bloomington, Indiana 47405, United States.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Dusanter
authors.affiliation: School of Public and Environmental Affairs, Indiana University , Bloomington, Indiana 47405, United States.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Griffith
authors.affiliation: School of Public and Environmental Affairs, Indiana University , Bloomington, Indiana 47405, United States.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Stevens
authors.affiliation: Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States.
authors.forename: Barry L
authors.initials: BL
authors.lastname: Lefer
authors.affiliation: Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.|Department of Earth and Planetary Science, University of California, Berkeley , Berkeley, California 94709, United States.
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Cohen
mesh_terms: D001272:Atmosphere / Q000737:chemistry*; D002140:California; D002947:Cities; D005453:Fluorescence; D009585:Nitrogen Dioxide / Q000032:analysis*; D009608:Nitrous Acid / Q000032:analysis*; D013499:Surface Properties; D013997:Time Factors
chemical_list: D009585:Nitrogen Dioxide; D009608:Nitrous Acid