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| Titel |
Increase in elemental carbon values between 1970 and 2004 observed in a 300-year ice core from Holtedahlfonna (Svalbard) |
| VerfasserIn |
M. M. Ruppel, E. Isaksson, J. Ström, E. Beaudon, J. Svensson, C. A. Pedersen, A. Korhola |
| 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 ; 14, no. 20 ; Nr. 14, no. 20 (2014-10-30), S.11447-11460 |
| Datensatznummer |
250119130
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| Publikation (Nr.) |
 copernicus.org/acp-14-11447-2014.pdf |
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| Zusammenfassung |
| Black carbon (BC) is a light-absorbing particle that warms the
atmosphere–Earth system. The climate effects of BC are amplified in the
Arctic, where its deposition on light surfaces decreases the albedo and
causes earlier melt of snow and ice. Despite its suggested significant role
in Arctic climate warming, there is little information on BC concentrations
and deposition in the past. Here we present results on BC (here
operationally defined as elemental carbon (EC)) concentrations and
deposition on a Svalbard glacier between 1700 and 2004. The inner part of a
125 m deep ice core from Holtedahlfonna glacier (79°8' N,
13°16' E, 1150 m a.s.l.) was melted, filtered through a quartz
fibre filter and analysed for EC using a thermal–optical method. The EC
values started to increase after 1850 and peaked around 1910, similar to ice
core records from Greenland. Strikingly, the EC values again increase
rapidly between 1970 and 2004 after a temporary low point around 1970,
reaching unprecedented values in the 1990s. This rise is not seen in
Greenland ice cores, and it seems to contradict atmospheric BC measurements
indicating generally decreasing atmospheric BC concentrations since 1989 in
the Arctic. For example, changes in scavenging efficiencies,
post-depositional processes and differences in the vertical distribution of
BC in the atmosphere are discussed for the differences between the Svalbard
and Greenland ice core records, as well as the ice core and atmospheric
measurements in Svalbard. In addition, the divergent BC trends between
Greenland and Svalbard ice cores may be caused by differences in the
analytical methods used, including the operational definitions of quantified
particles, and detection efficiencies of different-sized BC particles.
Regardless of the cause of the increasing EC values between 1970 and 2004,
the results have significant implications for the past radiative energy
balance at the coring site. |
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