Kozachek A., Mikhalenko V., Masson-Delmotte V., Ekaykin A., Ginot Patrick, Kutuzov S., Legrand M., Lipenkov V., Preunkert S. (2017). Large-scale drivers of Caucasus climate variability in meteorological records and Mt El'brus ice cores. Climate of the Past, 13 (5), p. 473-489. ISSN 1814-9324.
Titre du document
Large-scale drivers of Caucasus climate variability in meteorological records and Mt El'brus ice cores
Année de publication
2017
Auteurs
Kozachek A., Mikhalenko V., Masson-Delmotte V., Ekaykin A., Ginot Patrick, Kutuzov S., Legrand M., Lipenkov V., Preunkert S.
Source
Climate of the Past, 2017,
13 (5), p. 473-489 ISSN 1814-9324
A 181.8 m ice core was recovered from a borehole drilled into bedrock on the western plateau of Mt El'brus (43 degrees 20'53.9 ' N, 42 degrees 25'36.0 ' E; 5115m 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.
Plan de classement
Sciences du milieu [021]
;
Hydrologie [062]
Description Géographique
RUSSIE ; CAUCASE
Localisation
Fonds IRD [F B010070051]
Identifiant IRD
fdi:010070051
