Antarctic ozone hole modifies iodine geochemistry on the Antarctic Plateau

• Published in: Nature Communications
• Main Authors: Spolaor, A., Burgay, François, Fernández, Rafael P., Turetta, C., Cuevas, Carlos A., Kim, K., Kinnison, Douglas E., Lamarque, Jean-François, Blasi, Fabrizio de, Barbaro, E., Corella, Juan Pablo, Vallelonga, P., Frezzotti, Massimo, Barbante, C., Saiz-Lopez, A.
• Other Authors: European Commission, National Science Foundation (US), Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina), Universidad Nacional de Cuyo, Agencia Nacional de Promoción Científica y Tecnológica (Argentina), Korea Polar Research Institute, Ministero dell'Istruzione, dell'Università e della Ricerca
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Nature Publishing Group 2021
• Subjects: Antarctic; The Antarctic; Antarc*; Antarctica; Antartide; ice core
• Online Access: http://hdl.handle.net/10261/255127; https://doi.org/10.1038/s41467-021-26109-x; https://doi.org/10.13039/501100003074; https://doi.org/10.13039/501100002923; https://doi.org/10.13039/501100000780; https://doi.org/10.13039/100000001; https://doi.org/10.13039/501100005961; https://doi.org/10.13039/501100003407

9 pags., 3 figs. Polar stratospheric ozone has decreased since the 1970s due to anthropogenic emissions of chlorofluorocarbons and halons, resulting in the formation of an ozone hole over Antarctica. The effects of the ozone hole and the associated increase in incoming UV radiation on terrestrial and marine ecosystems are well established; however, the impact on geochemical cycles of ice photoactive elements, such as iodine, remains mostly unexplored. Here, we present the first iodine record from the inner Antarctic Plateau (Dome C) that covers approximately the last 212 years (1800-2012 CE). Our results show that the iodine concentration in ice remained constant during the pre-ozone hole period (1800-1974 CE) but has declined twofold since the onset of the ozone hole era (~1975 CE), closely tracking the total ozone evolution over Antarctica. Based on ice core observations, laboratory measurements and chemistry-climate model simulations, we propose that the iodine decrease since ~1975 is caused by enhanced iodine re-emission from snowpack due to the ozone hole-driven increase in UV radiation reaching the Antarctic Plateau. These findings suggest the potential for ice core iodine records from the inner Antarctic Plateau to be as an archive for past stratospheric ozone trends. This project received funding from the European Union’s Horizon 2020 Research and Innovation program under grant agreement no. 689443 via project iCUPE (Integrative and Comprehensive Understanding on Polar Environments), part of the European Commission (ERA-PLANET) and by the “Programma Nazionale per la Ricerca in Antartide” (PNRA, project number PNRA16_00295). This study also received funding from the European Research Council Executive Agency under the European Union’s Horizon 2020 Research and Innovation programme (Project ‘ERC-2016-COG 726349 CLIMAHAL’). NCAR is sponsored by the National Science Foundation under Grant Number 1852977. R.P.F. would like to express thanks for the financial support from CONICET-UNCuyo (SIIP-06/M111) and ...