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Titel |
In-situ measurements of atmospheric hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) at the Shangdianzi regional background station, China |
VerfasserIn |
B. Yao, M. K. Vollmer, L. X. Zhou, S. Henne, S. Reimann, P. C. Li, A. Wenger, M. Hill |
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 ; 12, no. 21 ; Nr. 12, no. 21 (2012-11-05), S.10181-10193 |
Datensatznummer |
250011560
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Publikation (Nr.) |
copernicus.org/acp-12-10181-2012.pdf |
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Zusammenfassung |
Atmospheric hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) were
measured in-situ at the Shangdianzi (SDZ) Global Atmosphere Watch (GAW) regional
background station, China, from May 2010 to May 2011. The time series for
five HFCs and three PFCs showed occasionally high-concentration events while
background conditions occurred for 36% (HFC-32) to 83% (PFC-218) of
all measurements. The mean mixing ratios during background conditions were
24.5 ppt (parts per trillion, 10−12, molar) for HFC-23, 5.86 ppt for
HFC-32, 9.97 ppt for HFC-125, 66.0 ppt for HFC-134a, 9.77 ppt for HFC-152a,
79.1 ppt for CF4, 4.22 ppt for PFC-116, and 0.56 ppt for PFC-218. The
background mixing ratios for the compounds at SDZ are consistent with those
obtained at mid to high latitude sites in the Northern Hemisphere.
North-easterly winds were associated with negative contributions to
atmospheric HFC and PFC loadings (mixing ratio anomalies weighted by time
associated with winds in a given sector), whereas south-westerly advection
(urban sector) showed positive loadings. Chinese emissions estimated by a
tracer ratio method using carbon monoxide as tracer were 3.6 ± 3.2 kt yr−1
for HFC-23, 4.3 ± 3.6 kt yr−1 for HFC-32, 2.7 ± 2.3 kt yr−1
for HFC-125, 6.0 ± 5.6 kt yr−1 for HFC-134a,
2.0 ± 1.8 kt yr−1 for HFC-152a, 2.4 ± 2.1 kt yr−1 for
CF4, 0.27 ± 0.26 kt yr−1 for PFC-116, and 0.061 ± 0.095 kt yr−1
for PFC-218. The lower HFC-23 emissions compared to earlier
studies may be a result of the HFC-23 abatement measures taken as part of
Clean Development Mechanism (CDM) projects that started in 2005. |
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