title: Amplified trace gas removal in the troposphere.
abstract: The degradation of trace gases and pollutants in the troposphere is dominated by their reaction with hydroxyl radicals (OH). The importance of OH rests on its high reactivity, its ubiquitous photochemical production in the sunlit atmosphere, and most importantly on its regeneration in the oxidation chain of the trace gases. In the current understanding, the recycling of OH proceeds through HO2 reacting with NO, thereby forming ozone. A recent field campaign in the Pearl River Delta, China, quantified tropospheric OH and HO2 concentrations and turnover rates by direct measurements. We report that concentrations of OH were three to five times greater than expected, and we propose the existence of a pathway for the regeneration of OH independent of NO, which amplifies the degradation of pollutants without producing ozone.
authors.affiliation: Forschungszentrum Jülich, Institut für Chemie und Dynamik der Geosphäre-2: Troposphäre, 52425 Jülich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hofzumahaus
authors.forename: Franz
authors.initials: F
authors.lastname: Rohrer
authors.forename: Keding
authors.initials: K
authors.lastname: Lu
authors.forename: Birger
authors.initials: B
authors.lastname: Bohn
authors.forename: Theo
authors.initials: T
authors.lastname: Brauers
authors.forename: Chih-Chung
authors.initials: CC
authors.lastname: Chang
authors.forename: Hendrik
authors.initials: H
authors.lastname: Fuchs
authors.forename: Frank
authors.initials: F
authors.lastname: Holland
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kita
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kondo
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Shengrong
authors.initials: S
authors.lastname: Lou
authors.forename: Min
authors.initials: M
authors.lastname: Shao
authors.forename: Limin
authors.initials: L
authors.lastname: Zeng
authors.forename: Andreas
authors.initials: A
authors.lastname: Wahner
authors.forename: Yuanhang
authors.initials: Y
authors.lastname: Zhang