title: Mass-independent sulfur isotopic compositions in stratospheric volcanic eruptions.
abstract: The observed mass-independent sulfur isotopic composition (Delta33S) of volcanic sulfate from the Agung (March 1963) and Pinatubo (June 1991) eruptions recorded in the Antarctic snow provides a mechanism for documenting stratospheric events. The sign of Delta33S changes over time from an initial positive component to a negative value. Delta33S is created during photochemical oxidation of sulfur dioxide to sulfuric acid on a monthly time scale, which indicates a fast process. The reproducibility of the results reveals that Delta33S is a reliable tracer to chemically identify atmospheric processes involved during stratospheric volcanism.
authors.affiliation: Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS/Université Joseph Fourier, 38400 St. Martin d'Hères, France. baroni@lgge.obs.ujf-grenoble.fr
authors.forename: Mélanie
authors.initials: M
authors.lastname: Baroni
authors.forename: Mark H
authors.initials: MH
authors.lastname: Thiemens
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Delmas
authors.forename: Joël
authors.initials: J
authors.lastname: Savarino