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| Titel |
Measurements of iodine monoxide at a semi polluted coastal location |
| VerfasserIn |
K. L. Furneaux, L. K. Whalley, D. E. Heard, H. M. Atkinson, W. J. Bloss, M. J. Flynn, M. W. Gallagher, T. Ingham, L. Kramer, J. D. Lee, R. Leigh, G. B. McFiggans, A. S. Mahajan, P. S. Monks, H. Oetjen, J. M. C. Plane, J. D. Whitehead |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 10, no. 8 ; Nr. 10, no. 8 (2010-04-20), S.3645-3663 |
| Datensatznummer |
250008363
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| Publikation (Nr.) |
 copernicus.org/acp-10-3645-2010.pdf |
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| Zusammenfassung |
| Point source measurements of IO by laser induced fluorescence spectroscopy
were made at a semi-polluted coastal location during the Reactive Halogens in
the Marine Boundary Layer (RHaMBLe) campaign in September 2006. The site, on
the NW French coast in Roscoff, was characterised by extensive intertidal
macroalgae beds which were exposed at low tide. The closest known iodine
active macroalgae beds were at least 300 m from the measurement point. From
20 days of measurements, IO was observed above the instrument limit of
detection on 14 days, of which a clear diurnal profile was observed on
11 days. The maximum IO mixing ratio was 30.0 pptv (10 s integration period)
during the day, amongst the highest concentrations ever observed in the
atmosphere, and 1–2 pptv during the night. IO concentrations were strongly
dependent on tidal height, the intensity of solar irradiation and
meteorological conditions. An intercomparison of IO measurements made using
point source and spatially averaged DOAS instruments confirms the presence of
hot-spots of IO caused by an inhomogeneous distribution of macroalgae. The
co-incident, point source measurement of IO and ultra fine particles
(2.5 nm≥d≥10 nm) displayed a strong correlation, providing
evidence that IO is involved in the production pathway of ultra fine
particles at coastal locations. Finally, a modelling study shows that high IO
concentrations which are likely to be produced in a macrolagae rich
environment can significantly perturb the concentrations of OH and HO2
radicals. The effect of IO on HOx is reduced as NOx
concentrations increase. |
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