1Institute of Geography, Russian Academy of Sciences, Moscow, Russia
2Arctic Environment Laboratory, Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia
3Univ. Grenoble Alpes, CNRS – UMR5183, Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE), Grenoble, France
4Arctic and Antarctic Research Institute, St. Petersburg, Russia
5Climate and Environmental Physics Group, University of Bern, Bern, Switzerland
6St. Petersburg State University, St. Petersburg, Russia
7Observatoire des Sciences de l'Univers de Grenoble, IRD UMS222, CNRS, Université Joseph Fourier Grenoble 1, Saint Martin d'Héres, France
8Department of Meteorology and Climatology, Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia
9Department of Earth and Environmental Sciences, Korea University, Seoul, South Korea
Received: 19 Apr 2015 – Published in The Cryosphere Discuss.: 16 Jul 2015
Abstract. 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.
Revised: 14 Oct 2015 – Accepted: 05 Nov 2015 – Published: 04 Dec 2015
Mikhalenko, V., Sokratov, S., Kutuzov, S., Ginot, P., Legrand, M., Preunkert, S., Lavrentiev, I., Kozachek, A., Ekaykin, A., Faïn, X., Lim, S., Schotterer, U., Lipenkov, V., and Toropov, P.: Investigation of a deep ice core from the Elbrus western plateau, the Caucasus, Russia, The Cryosphere, 9, 2253-2270, doi:10.5194/tc-9-2253-2015, 2015.