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Titel |
Investigation of a deep ice core from the Elbrus western plateau, the Caucasus, Russia |
VerfasserIn |
V. Mikhalenko, S. Sokratov, S. Kutuzov, P. Ginot, M. Legrand, S. Preunkert, I. Lavrentiev, A. Kozachek, A. Ekaykin, X. Faïn, S. Lim, U. Schotterer, V. Lipenkov, P. Toropov |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1994-0416
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Digitales Dokument |
URL |
Erschienen |
In: The Cryosphere ; 9, no. 6 ; Nr. 9, no. 6 (2015-12-04), S.2253-2270 |
Datensatznummer |
250116879
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Publikation (Nr.) |
copernicus.org/tc-9-2253-2015.pdf |
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Zusammenfassung |
A 182 m ice core was recovered from a borehole drilled into bedrock on the
western plateau of Mt. Elbrus (43°20´53.9'' N,
42°25´36.0'' E; 5115 m a.s.l.) in the Caucasus, Russia,
in 2009. This is the first ice core in the region that represents a
paleoclimate record that is practically undisturbed by seasonal melting.
Relatively high snow accumulation rates at the drilling site enabled the
analysis of the intraseasonal variability in climate proxies. Borehole
temperatures ranged from −17 °C at 10 m depth to
−2.4 °C at 182 m. A detailed radio-echo sounding survey
showed that the glacier thickness ranged from 45 m near the marginal
zone of the plateau up to 255 m at the glacier center. The ice core
has been analyzed for stable isotopes (δ18O and δD), major
ions (K+, Na+, Ca2+, Mg2+, NH4+, SO42-,
NO3-, Cl-, F-), succinic acid (HOOCCH2COOH), and tritium
content. The mean annual net accumulation rate of 1455 mm w.e. for
the last 140 years was estimated from distinct annual oscillations of
δ18O, δD, succinic acid, and NH4+. Annual layer
counting also helped date the ice core, agreeing with the absolute markers of
the tritium 1963 bomb horizon located at the core depth of
50.7 m w.e. and the sulfate peak of the Katmai eruption (1912) at
87.7 m w.e. According to mathematical modeling results, the ice age at
the maximum glacier depth is predicted to be ~ 660 years BP.
The 2009 borehole is located downstream from this point, resulting in an
estimated basal ice age of less than 350–400 years BP at the drilling site.
The glaciological and initial chemical analyses from the Elbrus ice core help
reconstruct the atmospheric history of the European region. |
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