Bromine, iodine and sodium in surface snow along the 2013 Talos Dome – GV7 traverse (Northern Victoria Land, East Antarctica)
Niccolò Maffezzoli1, Andrea Spolaor2,3, Carlo Barbante2,3, Michele Bertò2, Massimo Frezzotti4, and Paul Vallelonga11Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, Copenhagen Ø 2100, Denmark 2Ca'Foscari University of Venice, Department of Environmental Science, Informatics and Statistics, Via Torino 155, 30170 Mestre, Venice, Italy 3Institute for the Dynamics of Environmental Processes, IDPA-CNR, Via Torino 155, 30170 Mestre, Venice, Italy 4ENEA, SP Anguillarese 301, 00123 Rome, Italy
Received: 30 Sep 2016 – Accepted for review: 12 Oct 2016 – Discussion started: 17 Oct 2016
Abstract. Halogen chemistry in the polar regions occurs through the release of sea salt rich aerosols from sea ice surfaces and organic compounds from algae colonies living within the sea ice environment. Measurements of halogen species in polar snow samples are limited to a few sites although they are shown to be closely related to sea ice extent. We examine here total bromine, iodine and sodium concentrations in a series of 2 m cores collected during a traverse from Talos Dome (72°48' S, 159°06' E) to GV7 (70°41' S, 158°51' E), analyzed by Inductively Coupled Plasma Sector Field Mass Spectrometry (ICP-SFMS) at a resolution of 5 cm.
We find a distinct seasonality of the bromine enrichment signal in all cores, with maxima during the austral late spring. Iodine showed average concentrations of 0.04 ppb with little variability. No distinct seasonality was found for iodine and sodium.
The transect revealed homogeneous fluxes for the three chemical species along the transect, due to competing effects of air masses originating from the Ross Sea and the Southern Ocean. The flux measurements are consistent with the uniform values of BrO and IO detected from satellite observations. Similar trends are found for annual bromine enrichment and 130–190° E First Year Sea Ice for the 2010–2013 period.
Maffezzoli, N., Spolaor, A., Barbante, C., Bertò, M., Frezzotti, M., and Vallelonga, P.: Bromine, iodine and sodium in surface snow along the 2013 Talos Dome – GV7 traverse (Northern Victoria Land, East Antarctica), The Cryosphere Discuss., doi:10.5194/tc-2016-220, in review, 2016.