title: Evidence of reactive aromatics as a major source of peroxy acetyl nitrate over China.
abstract: We analyze the observations of near-surface peroxy acetyl nitrate (PAN) and its precursors in Beijing, China in August of 2007. The levels of PAN are remarkably high (up to 14 ppbv), surpassing those measured over other urban regions in recent years. Analyses employing a 1-D version of a chemical transport model (Regional chEmical and trAnsport Model, REAM) indicate that aromatic non-methane hydrocarbons (NMHCs) are the dominant (55-75%) PAN source. The major oxidation product of aromatics that produces acetyl peroxy radicals is methylglyoxal (MGLY). PAN and O(3) in the observations are correlated at daytime; aromatic NMHCs appear to play an important role in O(3) photochemistry. Previous NMHC measurements indicate the presence of reactive aromatics at high levels over broad polluted regions of China. Aromatics are often ignored in global and (to a lesser degree) regional 3D photochemical transport models; their emissions over China as well as photochemistry are quite uncertain. Our findings suggest that critical assessments of aromatics emissions and chemistry (such as the yields of MGLY) are necessary to understand and assess ozone photochemistry and regional pollution export in China.
authors: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA. zhen.liu@eas.gatech.edu
authors: Zhen
authors: Z
authors: Liu
authors: Yuhang
authors: Y
authors: Wang
authors: Dasa
authors: D
authors: Gu
authors: Chun
authors: C
authors: Zhao
authors: L Gregory
authors: LG
authors: Huey
authors: Robert
authors: R
authors: Stickel
authors: Jin
authors: J
authors: Liao
authors: Min
authors: M
authors: Shao
authors: Tong
authors: T
authors: Zhu
authors: Limin
authors: L
authors: Zeng
authors: Shaw-Chen
authors: SC
authors: Liu
authors: Chih-Chung
authors: CC
authors: Chang
authors: Antonio
authors: A
authors: Amoroso
authors: Francesca
authors: F
authors: Costabile
mesh_terms: D002681:China; D006841:Hydrocarbons, Aromatic / Q000032:analysis*; D008956:Models, Chemical; D009038:Motion; D010463:Peracetic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D013997:Time Factors
chemical_list: D006841:Hydrocarbons, Aromatic; D010463:Peracetic Acid; C004185:peroxyacetyl nitrate