 |
| Titel |
The isotopic record of Northern Hemisphere atmospheric carbon monoxide since 1950: implications for the CO budget |
| VerfasserIn |
Z. Wang, J. Chappellaz, P. Martinerie, K. Park, V. Petrenko, E. Witrant, L. K. Emmons, T. Blunier, C. A. M. Brenninkmeijer, J. E. Mak |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 12, no. 10 ; Nr. 12, no. 10 (2012-05-16), S.4365-4377 |
| Datensatznummer |
250011155
|
| Publikation (Nr.) |
 copernicus.org/acp-12-4365-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| We present a 60-year record of the stable isotopes of atmospheric carbon
monoxide (CO) from firn air samples collected under the framework of the
North Greenland Eemian Ice Drilling (NEEM) project. CO concentration,
δ13C, and δ18O of CO were measured by gas
chromatography/isotope ratio mass spectrometry (gc-IRMS) from trapped gases
in the firn. We applied LGGE-GIPSA firn air models (Witrant et al., 2011) to
correlate gas age with firn air depth and then reconstructed the trend of
atmospheric CO and its stable isotopic composition at high northern
latitudes since 1950. The most probable firn air model scenarios show that
δ13C decreased slightly from −25.8‰ in 1950 to −26.4‰ in 2000,
then decreased more significantly to −27.2‰ in 2008. δ18O
decreased more regularly from 9.8‰ in 1950 to 7.1‰ in 2008. Those same
scenarios show CO concentration increased gradually from 1950 and peaked in
the late 1970s, followed by a gradual decrease to present day values
(Petrenko et al., 2012). Results from an
isotope mass balance model indicate that a slight increase, followed by a
large reduction, in CO derived from fossil fuel combustion has occurred since
1950. The reduction of CO emission from fossil fuel combustion after the
mid-1970s is the most plausible mechanism for the drop of CO concentration
during this time. Fossil fuel CO emissions decreased as a result of the
implementation of catalytic converters and the relative growth of diesel
engines, in spite of the global vehicle fleet size having grown several fold
over the same time period. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|