Synchronous volcanic eruptions and abrupt climate change ∼17.7 ka plausibly linked by stratospheric ozone depletion. ...

• Main Authors: McConnell, Joseph R, Burke, Andrea, Dunbar, Nelia W, Köhler, Peter, Thomas, Jennie L, Arienzo, Monica M, Chellman, Nathan J, Maselli, Olivia J, Sigl, Michael, Adkins, Jess F, Baggenstos, Daniel, Burkhart, John F, Brook, Edward J, Buizert, Christo, Cole-Dai, Jihong, Fudge, TJ, Knorr, Gregor, Graf, Hans-F, Grieman, Mackenzie M, Iverson, Nels, McGwire, Kenneth C, Mulvaney, Robert, Paris, Guillaume, Rhodes, Rachael H, Saltzman, Eric S, Severinghaus, Jeffrey P, Steffensen, Jørgen Peder, Taylor, Kendrick C, Winckler, Gisela
• Format: Article in Journal/Newspaper
• Language: English
• Published: Proceedings of the National Academy of Sciences 2017
• Subjects: aerosol; climate; deglaciation; ozone; volcanism; Antarctic; Byrd; Mount Takahe; Takahe; West Antarctic Ice Sheet; Antarc*; ice core; Ice Sheet
• Online Access: https://dx.doi.org/10.17863/cam.30535; https://www.repository.cam.ac.uk/handle/1810/283172

Glacial-state greenhouse gas concentrations and Southern Hemisphere climate conditions persisted until ∼17.7 ka, when a nearly synchronous acceleration in deglaciation was recorded in paleoclimate proxies in large parts of the Southern Hemisphere, with many changes ascribed to a sudden poleward shift in the Southern Hemisphere westerlies and subsequent climate impacts. We used high-resolution chemical measurements in the West Antarctic Ice Sheet Divide, Byrd, and other ice cores to document a unique, ∼192-y series of halogen-rich volcanic eruptions exactly at the start of accelerated deglaciation, with tephra identifying the nearby Mount Takahe volcano as the source. Extensive fallout from these massive eruptions has been found >2,800 km from Mount Takahe. Sulfur isotope anomalies and marked decreases in ice core bromine consistent with increased surface UV radiation indicate that the eruptions led to stratospheric ozone depletion. Rather than a highly improbable coincidence, circulation and climate ...