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Titel |
ACTRIS non-methane hydrocarbon intercomparison experiment in Europe to support WMO GAW and EMEP observation networks |
VerfasserIn |
C. C. Hoerger, A. Claude, C. Plass-Duelmer, S. Reimann, E. Eckart, R. Steinbrecher, J. Aalto, J. Arduini, N. Bonnaire, J. N. Cape, A. Colomb, R. Connolly, J. Diskova, P. Dumitrean, C. Ehlers, V. Gros, H. Hakola, M. Hill, J. R. Hopkins, J. Jager, R. Junek, M. K. Kajos, D. Klemp, M. Leuchner, A. C. Lewis, N. Locoge, M. Maione, D. Martin, K. Michl, E. Nemitz, S. O'Doherty, P. Pérez Ballesta, T. M. Ruuskanen, S. Sauvage, N. Schmidbauer, T. G. Spain, E. Straube, M. Vana, M. K. Vollmer, R. Wegener, A. Wenger |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1867-1381
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Measurement Techniques ; 8, no. 7 ; Nr. 8, no. 7 (2015-07-08), S.2715-2736 |
Datensatznummer |
250116475
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Publikation (Nr.) |
copernicus.org/amt-8-2715-2015.pdf |
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Zusammenfassung |
The performance of 18 European institutions involved in long-term
non-methane hydrocarbon (NMHC) measurements in ambient air within the
framework of the Global Atmosphere Watch (GAW) and the European Monitoring and
Evaluation Programme (EMEP) was assessed with respect to data quality
objectives (DQOs) of ACTRIS (Aerosols, Clouds, and Trace gases Research
InfraStructure Network) and GAW. Compared to previous intercomparison
studies the DQOs define a novel approach to assess and ensure a high quality
of the measurements. Having already been adopted by GAW, the ACTRIS DQOs are demanding
with deviations to a reference value of less than 5 % and a repeatability
of better than 2 % for NMHC mole fractions above 0.1 nmol mol−1.
The participants of the intercomparison analysed two dry gas mixtures in
pressurised cylinders, a 30-component NMHC mixture in nitrogen
(NMHC_N2) at approximately 1 nmol mol−1 and a whole air
sample (NMHC_air), following a standardised operation
procedure including zero- and calibration gas measurements. Furthermore,
participants had to report details on their instruments and assess their
measurement uncertainties.
The NMHCs were analysed either by gas chromatography–flame ionisation
detection (GC-FID) or by gas chromatography–mass spectrometry (GC-MS). For
the NMHC_N2 measurements, 62 % of the reported values
were within the 5 % deviation class corresponding to the ACTRIS DQOs. For
NMHC_air, generally more frequent and larger deviations to
the assigned values were observed, with 50 % of the reported values within
the 5 % deviation class. Important contributors to the poorer performance
in NMHC_air compared to NMHC_N2 were a
more complex matrix and a larger span of NMHC mole fractions (0.03–2.5 nmol mol−1).
The performance of the participating laboratories were affected
by the different measurement procedures such as the usage of a two-step vs.
a one-step calibration, breakthroughs of C2–C3 hydrocarbons in the
focussing trap, blank values in zero-gas measurements (especially for those
systems using a Nafion® Dryer), adsorptive losses of aromatic
compounds, and insufficient chromatographic separation. |
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