Holocene atmospheric iodine evolution over the North Atlantic

• Published in: Climate of the Past
• Main Authors: Corella, Juan Pablo, Maffezzoli, N., Cuevas, Carlos A., Vallelonga, P., Spolaor, A., Cozzi, G., Müller, J., Vinther, B., Barbante, C., Astrid Kjær, H., Edwards, R., Saiz-Lopez, A.
• Other Authors: Consejo Superior de Investigaciones Científicas (España), Danish Research Council, National Science Foundation (US), European Commission, Helmholtz Association, SCOAP
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: European Geosciences Union 2019
• Subjects: Arctic; Cierva; Greenland; Pablo; Renland; Alfred Wegener Institute; Global warming; Ice cap; ice core; North Atlantic
• Online Access: http://hdl.handle.net/10261/205223; https://doi.org/10.5194/cp-15-2019-2019; https://doi.org/10.13039/100000001; https://doi.org/10.13039/501100000780; https://doi.org/10.13039/501100001656; https://doi.org/10.13039/501100003339

12 pags., 3 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0 Atmospheric iodine chemistry has a large influence on the oxidizing capacity and associated radiative impacts in the troposphere. However, information on the evolution of past atmospheric iodine levels is restricted to the industrial period while its long-term natural variability remains unknown. The current levels of iodine in the atmosphere are controlled by anthropogenic ozone deposition to the ocean surface. Here, using high-resolution geochemical measurements from coastal eastern Greenland ReCAP (REnland ice CAP project) ice core, we report the first record of atmospheric iodine variability in the North Atlantic during the Holocene (i.e., the last 11 700 years). Surprisingly, our results reveal that the highest iodine concentrations in the record were found during the Holocene Thermal Maximum (HTM; ∼ 11 500-5500 years before-present). These high iodine levels could be driven by marine primary productivity resulting in an Early Holocene >biological iodine explosion>. The high and stable iodine levels during this past warm period are a useful observational constraint on projections of future changes in Arctic atmospheric composition and climate resulting from global warming. This work was supported by CSIC. The RECAP ice coring effort was financed by the Danish Research Council through a Sapere Aude grant, the NSF through the Division of Polar Programs, the Alfred Wegener Institute, and the European Research Council under the European Community’s Seventh Framework Programme (FP7/2007-2013), and an ERC grant agreement 610055 through the Ice2Ice project and the Early Human Impact project (267696). Juan Pablo Corella had a Juan de la Cierva – Incorporación postdoctoral contract (ref. IJCI-2015-23839). Juliane Müller received funding through a Helmholtz Research grant VH-NG-1101. This study has received funding from the European Research Council Executive Agency under the European Union’s Horizon 2020 Research and ...