2600-years of stratospheric volcanism through sulfate isotopes

• Published in: Nature Communications
• Main Authors: Gautier, E., Savarino, J., Hoek, J., Erbland, J., Caillon, N., Hattori, S., Yoshida, N., Albalat, E., Albarède, F., Farquhar, J.
• Other Authors: Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Tokyo Institute of Technology Tokyo (TITECH), Frontier Collaborative Research Center (FCRC), École normale supérieure - Lyon (ENS Lyon), University of Maryland College Park, University of Maryland System
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Cryospheric science; [SDE.MCG]Environmental Sciences/Global Changes; Antarctic; Greenland; Antarc*; Antarctica; ice core
• Online Access: https://hal.archives-ouvertes.fr/hal-02350375; https://hal.archives-ouvertes.fr/hal-02350375/document; https://hal.archives-ouvertes.fr/hal-02350375/file/s41467-019-08357-0.pdf; https://doi.org/10.1038/s41467-019-08357-0

International audience High quality records of stratospheric volcanic eruptions, required to model past climate variability, have been constructed by identifying synchronous (bipolar) volcanic sulfate horizons in Greenland and Antarctic ice cores. Here we present a new 2600-year chronology of stratospheric volcanic events using an independent approach that relies on isotopic signatures (Δ 33 S and in some cases Δ 17 O) of ice core sulfate from five closely-located ice cores from Dome C, Antarctica. The Dome C stratospheric reconstruction provides independent validation of prior reconstructions. The isotopic approach documents several high-latitude stratospheric events that are not bipolar, but climatically-relevant, and diverges deeper in the record revealing tropospheric signals for some previously assigned bipolar events. Our record also displays a collapse of the Δ 17 O anomaly of sulfate for the largest volcanic eruptions, showing a further change in atmospheric chemistry induced by large emissions. Thus, the refinement added by considering both isotopic and bipolar correlation methods provides additional levels of insight for climate-volcano connections and improves ice core volcanic reconstructions.