1Department of Environmental Sciences, Informatics and Statistics, University Ca' Foscari of Venice, Dorsoduro 2137, 30123 Venice, Italy
2Institute for the Dynamics of Environmental Processes – CNR, University of Venice, Dorsoduro 2137, 30123 Venice, Italy
3Institute of Geology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia
4Norwegian Polar Institute, Fram Centre, Hjalmar Johansens gt. 14, 9296 Tromsø, Norway
5Department of Geosciences, University of Oslo, P.O. Box 1047, Blindern, 0316 Oslo, Norway
6Centre for Ice and Climate, Niels Bohr Institute, Juliane Maries Vej 30, 2100 Copenhagen, Denmark
7Department of Imaging and Applied Physics, Curtin University, Kent St, Bentley WA 6102, Australia
8School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK
Received: 28 Jan 2013 – Discussion started: 08 Mar 2013
Abstract. Sea ice is an important parameter in the climate system and its changes impact upon the polar albedo and atmospheric and oceanic circulation. Iodine (I) and bromine (Br) have been measured in a shallow firn core drilled at the summit of the Holtedahlfonna glacier (Northwest Spitsbergen, Svalbard). Changing I concentrations can be linked to the March–May maximum sea ice extension. Bromine enrichment, indexed to the Br / Na sea water mass ratio, appears to be influenced by changes in the seasonal sea ice area. I is emitted from marine biota and so the retreat of March–May sea ice coincides with enlargement of the open-ocean surface which enhances marine primary production and consequent I emission. The observed Br enrichment could be explained by greater Br emissions during the Br explosions that have been observed to occur mainly above first year sea ice during the early springtime. In this work we present the first comparison between halogens in surface snow and Arctic sea ice extension. Although further investigation is required to characterize potential depositional and post-depositional processes, these preliminary findings suggest that I and Br can be linked to variability in the spring maximum sea ice extension and seasonal sea ice surface area.
Revised: 20 Sep 2013 – Accepted: 30 Sep 2013 – Published: 31 Oct 2013
Spolaor, A., Gabrieli, J., Martma, T., Kohler, J., Björkman, M. B., Isaksson, E., Varin, C., Vallelonga, P., Plane, J. M. C., and Barbante, C.: Sea ice dynamics influence halogen deposition to Svalbard, The Cryosphere, 7, 1645-1658, doi:10.5194/tc-7-1645-2013, 2013.