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| Titel |
Deposition of terpenes to vegetation - a paradigm shift towards bidirectional VOC exchange? |
| VerfasserIn |
I. Bamberger, L. Hörtnagl, T. Ruuskanen, R. Schnitzhofer, M. Müller, M. Graus, T. Karl, G. Wohlfahrt, A. Hansel |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250065735
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| Zusammenfassung |
| Biogenic volatile organic compounds (BVOCs) are important precursors for secondary
organic aerosol (SOA) formation (Hallquist et al., 2009). In addition reactive BVOCs play a
crucial role in local tropospheric ozone production (Atkinson, 2000). According to the
present scientific understanding vegetation is recognized as a major VOC emission source
rather than a deposition sink. Our recent observations however demonstrate that an uptake of
terpene compounds to mountain grassland can be significant - at least under certain
atmospheric conditions.
After a severe hailstorm volume mixing ratios (VMR) of locally emitted terpene compounds
originating from conifers located at the mountain slopes were strongly enhanced, even during
daytime hours. Weeks after the hailstorm our PTR-MS and PTR-time-of-flight
(PTR-TOF) instruments still measured deposition fluxes of monoterpenes (m/z
137.133), sesquiterpenes (m/z 205.195), and oxygenated terpenes (m/z 153.128) to the
grassland. The total amount of terpenoids (on a carbon basis) deposited to the grassland
during the weeks after the hailstorm is comparable to the total methanol emission
of the entire growing season (Bamberger et al., 2011). These findings pose the
question whether the terminology should be adjusted from VOC emission to VOC
exchange.
References:
R. Atkinson (2000), Atmospheric chemistry of VOCs and NOx, Atmos. Environ. 34,
2063-2101.
Bamberger, I., L. Hörtnagl, T. M. Ruuskanen, R. Schnitzhofer, M. Müller, M. Graus, T. Karl,
G. Wohlfahrt, and A. Hansel (2011), Deposition fluxes of terpenes over grassland, J.
Geophys. Res., 116, D14305, doi:10.1029/2010JD015457.
M. Hallquist et al. (2009), The formation, properties and impact of secondary organic
aerosol: current and emerging issues, Atmos. Chem. Phys., 9, 5155-5236. |
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