TY  - JOUR
AU  - Baroni, Mlanie
AU  - Savarino, Jol
AU  - Cole-Dai, J.
AU  - Rai, V. K.
AU  - Thiemens, M. H.
PY  - 2008//
TI  - Anomalous sulfur isotope compositions of volcanic sulfate over the last millennium in Antarctic ice cores
JO  - J. Geophys. Res.
SP  - D20112
VL  - 113
IS  - D20
PB  - AGU
KW  - sulfur isotope anomaly
KW  - volcanic eruption
KW  - ice cores
KW  - 0370 Atmospheric Composition and Structure: Volcanic effects
KW  - 0454 Biogeosciences: Isotopic composition and chemistry
KW  - 0473 Biogeosciences: Paleoclimatology and paleoceanography
KW  - 0724 Cryosphere: Ice cores
KW  - 1041 Geochemistry: Stable isotope geochemistry
N2  - The reconstruction of past volcanism from glaciological archives is based on the measurement of sulfate concentrations in ice. This method does not allow a proper evaluation of the climatic impact of an eruption owing to the uncertainty in classifying an event between stratospheric or tropospheric. This work develops a new method, using anomalous sulfur isotope composition of volcanic sulfate in order to identify stratospheric eruptions over the last millennium. The advantages and limits of this new method are established with the examination of the 10 largest volcanic signals in ice cores from Dome C and South Pole, Antarctica. Of the 10, seven are identified as stratospheric eruptions. Among them, three have been known to be stratospheric (Tambora, Kuwae, the 1259 Unknown Event) and they exhibit anomalous sulfur isotope compositions. Three unknown events (circa 1277, 1230, 1170 A.D.) and the Serua eruption have been identified as stratospheric eruptions, which suggests for the first time that they could have had significant climatic impact. However, the Kuwae and the 1259 Unknown Event stratospheric eruptions exhibit different anomalous sulfur isotope compositions between South Pole and Dome C samples. Differences in sulfate deposition and preservation patterns between the two sites can help explain these discrepancies. This study shows that the presence of an anomalous sulfur isotope composition of volcanic sulfate in ice core indicates a stratospheric eruption, but the absence of such composition does not necessarily lead to the conclusion of a tropospheric process because of differences in the sulfate deposition on the ice sheet.
SN  - 0148-0227
UR  - http://dx.doi.org/10.1029/2008JD010185
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=6048), last updated on Tue, 13 Apr 2010 11:08:23 +0200
ID  - Baroni_etal2008
ER  -