Open AccessNight‐time NO 3 and OH radical concentrations in the United Kingdom inferred from hydrocarbon measurements
Author(s) -
Khan M. A. H.,
Ashfold M. J.,
Nickless G.,
Martin D.,
Watson L. A.,
Hamer P. D.,
Wayne R. P.,
CanosaMas C. E.,
Shallcross D. E.
Publication year - 2008
Publication title -
atmospheric science letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.951
H-Index - 45
ISSN - 1530-261X
DOI - 10.1002/asl.175
Subject(s) - hydrocarbon , spring (device) , atmospheric sciences , range (aeronautics) , chemistry , environmental science , molecule , environmental chemistry , meteorology , analytical chemistry (journal) , geology , materials science , physics , thermodynamics , organic chemistry , composite material
Abstract The hydrocarbon decay method (Rivett et al. , 2003) has been used to analyse hydrocarbon data from four contrasting sites in the United Kingdom to estimate night‐time levels of NO 3 and OH. Remarkably consistent results emerge using alkenes, revealing NO 3 and OH levels in the range of 0.01–10 ppt and 1 × 10 4 − 1 × 10 6 molecule cm −3 , respectively. Weak seasonal cycles are observed where NO 3 levels peak in spring and OH in summer. Analysis using alkanes suggests that Cl atom levels of around 2 × 10 4 molecule cm −3 may be present. How Cl may be formed at night in such high quantities is unknown and may not be the answer to the disparity between the two methods. Copyright © 2008 Royal Meteorological Society