title: Stratospheric Ozone destruction by the Bronze-Age Minoan eruption (Santorini Volcano, Greece).
abstract: The role of volcanogenic halogen-bearing (i.e. chlorine and bromine) compounds in stratospheric ozone chemistry and climate forcing is poorly constrained. While the 1991 eruption of Pinatubo resulted in stratospheric ozone loss, it was due to heterogeneous chemistry on volcanic sulfate aerosols involving chlorine of anthropogenic rather than volcanogenic origin, since co-erupted chlorine was scavenged within the plume. Therefore, it is not known what effect volcanism had on ozone in pre-industrial times, nor what will be its role on future atmospheres with reduced anthropogenic halogens present. By combining petrologic constraints on eruption volatile yields with a global atmospheric chemistry-transport model, we show here that the Bronze-Age 'Minoan' eruption of Santorini Volcano released far more halogens than sulfur and that, even if only 2% of these halogens reached the stratosphere, it would have resulted in strong global ozone depletion. The model predicts reductions in ozone columns of 20 to >90% at Northern high latitudes and an ozone recovery taking up to a decade. Our findings emphasise the significance of volcanic halogens for stratosphere chemistry and suggest that modelling of past and future volcanic impacts on Earth's ozone, climate and ecosystems should systematically consider volcanic halogen emissions in addition to sulfur emissions.
authors.affiliation: 1] Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France [2] CNRS, ISTO, UMR 7327, 45071 Orléans, France [3] BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France.
authors.forename: Anita
authors.initials: A
authors.lastname: Cadoux
authors.affiliation: 1] Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France [2] CNRS, ISTO, UMR 7327, 45071 Orléans, France [3] BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Scaillet
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06 ; Université Versailles St-Quentin; CNRS/INSU, LATMOS-IPSL, France.
authors.forename: Slimane
authors.initials: S
authors.lastname: Bekki
authors.affiliation: University of Cambridge, Department of Geography, Downing Place, Cambridge CB2 3EN, United Kingdom.
authors.forename: Clive
authors.initials: C
authors.lastname: Oppenheimer
authors.affiliation: Laboratoire Magmas et Volcans, Université Blaise Pascal-CNRS-IRD, OPGC, 5 rue Kessler, 63038 Clermont-Ferrand, France.
authors.forename: Timothy H
authors.initials: TH
authors.lastname: Druitt