Physico-ecobiogeochemistry of East Antarctic pack ice during the winter-spring transition

• Published in: Deep Sea Research Part II: Topical Studies in Oceanography
• Main Authors: Meiners, KM, Norman, L, Granskog, MA, Krell, A, Heil, P, Thomas, DN
• Format: Article in Journal/Newspaper
• Language: English
• Published: Pergamon-Elsevier Science Ltd 2011
• Subjects: Biological Sciences; Ecology; Marine and Estuarine Ecology (incl. Marine Ichthyology); Antarctic; East Antarctica; Antarc*; Antarctica; Sea ice
• Online Access: https://doi.org/10.1016/j.dsr2.2010.10.033; http://ecite.utas.edu.au/75536

Our study provides information on the relationships between physical, chemical, and biologicalproperties of East Antarctic sea ice sampled as part of the Sea Ice Physics and Ecosystem eXperiment(SIPEX) during the winter-spring transition in 2007. The sampled sea ice showed a high contribution of granular ice, indicating the turbulent conditions during sea ice formation off East Antarctica. The sea icewas cold, with brine volumes often below or very close to the theoretical percolation threshold of sea ice. Dissolved inorganic nutrient concentrations showed both positive and negative deviations from theoretical dilution lines, indicating both nutrient uptake as well as nutrient remineralisation in seaice brines. Cold temperatures, high brine salinities, and low brine volumes limited high ice algal biomass to the warmer and more porous sea ice layers at the icewater interface. We hypothesise that East Antarctic sea ice shows generally low ice algal biomass accumulation due to a combination of relativelylow snowloading, relatively cold ice temperatures, and short persistence of sea ice into the warm forcing regime, all of which prevent the development of significant internal and surface communities.