 |
| Titel |
Volatile organic compounds in the western Mediterranean basin: urban and rural winter measurements during the DAURE campaign |
| VerfasserIn |
R. Seco, J. Peñuelas, I. Filella, J. Llusià, S. Schallhart, A. Metzger, M. Müller, A. Hansel |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 8 ; Nr. 13, no. 8 (2013-04-25), S.4291-4306 |
| Datensatznummer |
250018608
|
| Publikation (Nr.) |
 copernicus.org/acp-13-4291-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| Atmospheric volatile organic compounds (VOCs) have key environmental and
biological roles, but little is known about the daily VOC mixing ratios in
Mediterranean urban and natural environments. We measured VOC mixing ratios
concurrently at an urban and a rural site during the winter DAURE campaign
in the northeastern Iberian Peninsula, by means of PTR-MS at both locations:
a PTR-Quad-MS at the urban site and a PTR-ToF-MS at the rural site. All VOC
mixing ratios measured were higher at the urban site (e.g. acetaldehyde,
isoprene, benzene, and toluene with averages up to 1.68, 0.31, 0.58 and 2.71
ppbv, respectively), with the exception of some short-chain oxygenated VOCs
such as acetone (with similar averages of 0.7–1.6 ppbv at both sites). The
average diurnal pattern also differed between the sites. Most of the VOCs at
the urban location showed their highest mixing ratios in the morning and
evening. These peaks coincided with traffic during rush hour, the main
origin of most of the VOCs analyzed. Between these two peaks, the sea breeze
transported the urban air inland, thus helping to lower the VOC loading at
the urban site. At the rural site, most of the measured VOCs were advected
by the midday sea breeze, yielding the highest daily VOC mixing ratios (e.g.
acetaldehyde, isoprene, benzene, and toluene with averages up to 0.65, 0.07,
0.19, and 0.41 ppbv, respectively). Only biogenic monoterpenes showed a
clear local origin at this site. In addition, the concentrations of fine
particulate matter observed at both sites, together with the synoptic
meteorological conditions and radio-sounding data, allowed the
identification of different atmospheric scenarios that had a clear influence
on the measured VOC mixing ratios. These results highlight the differences
and relationships in VOC mixing ratios between nearby urban and rural areas
in Mediterranean regions. Further research in other urban-rural areas is
warranted to better understand the urban-rural influence on atmospheric VOC
mixing ratios under different atmospheric conditions. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|