Journal cover Journal topic
Climate of the Past An interactive open-access journal of the European Geosciences Union
Clim. Past, 13, 473-489, 2017
© Author(s) 2017. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
12 May 2017
Large-scale drivers of Caucasus climate variability in meteorological records and Mt El'brus ice cores
Anna Kozachek1,2,3, Vladimir Mikhalenko2, Valérie Masson-Delmotte3, Alexey Ekaykin1,4, Patrick Ginot5,6, Stanislav Kutuzov2, Michel Legrand5, Vladimir Lipenkov1, and Susanne Preunkert5 1Climate and Environmental Research Laboratory, Arctic and Antarctic Research Institute, St Petersburg, 199397, Russia
2Institute of Geography, Russian Academy of Sciences, Moscow, 119017, Russia
3Laboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS/UVSQ/IPSL, Gif-sur-Yvette, 91191, France
4Institute of Earth Sciences, St Petersburg State University, St Petersburg, 199178, Russia
5Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS/UGA, Grenoble, 38400, France
6Observatoire des Sciences de l'Univers de Grenoble, IRD/UGA/CNRS, Grenoble, 38400, France
Abstract. A 181.8 m ice core was recovered from a borehole drilled into bedrock on the western plateau of Mt El'brus (43°20′53.9′′ N, 42°25′36.0′′ E; 5115 m a.s.l.) in the Caucasus, Russia, in 2009 (Mikhalenko et al., 2015). Here, we report on the results of the water stable isotope composition from this ice core with additional data from the shallow cores. The distinct seasonal cycle of the isotopic composition allows dating by annual layer counting. Dating has been performed for the upper 126 m of the deep core combined with 20 m from the shallow cores. The whole record covers 100 years, from 2013 back to 1914. Due to the high accumulation rate (1380 mm w.e. year−1) and limited melting, we obtained isotopic composition and accumulation rate records with seasonal resolution. These values were compared with available meteorological data from 13 weather stations in the region and also with atmosphere circulation indices, back-trajectory calculations, and Global Network of Isotopes in Precipitation (GNIP) data in order to decipher the drivers of accumulation and ice core isotopic composition in the Caucasus region. In the warm season (May–October) the isotopic composition depends on local temperatures, but the correlation is not persistent over time, while in the cold season (November–April), atmospheric circulation is the predominant driver of the ice core's isotopic composition. The snow accumulation rate correlates well with the precipitation rate in the region all year round, which made it possible to reconstruct and expand the precipitation record at the Caucasus highlands from 1914 until 1966, when reliable meteorological observations of precipitation at high elevation began.

Citation: Kozachek, A., Mikhalenko, V., Masson-Delmotte, V., Ekaykin, A., Ginot, P., Kutuzov, S., Legrand, M., Lipenkov, V., and Preunkert, S.: Large-scale drivers of Caucasus climate variability in meteorological records and Mt El'brus ice cores, Clim. Past, 13, 473-489, doi:10.5194/cp-13-473-2017, 2017.
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