Granskog, M. (2004). Investigations into the physical and chemical properties of Baltic Sea ice. Ph.D. thesis, University of Helsinki, Helsinki.
Abstract: Sea ice is a key component of polar and sub-polar seas, including the Baltic Sea. It not only affects climate, from global to local scales, but also strongly modifies the conditions in the marine environment through freezing and eventual melt in several ways. The role of snow in sea ice growth is presumed to be high in the Baltic Sea, although very little quantitative information is available on the contribution of precipitation to ice growth in the Baltic Sea. Even less is known about the chemistry of sea ice and its role as a moderator of (bio)geochemical cycling and budgets of elements in the Baltic Sea. The aim of this Thesis is to shed new light on these matters.The importance of snow and precipitation on the growth of Baltic Sea ice is vital. For the first time, the stable oxygen isotopic composition of ice, snow and water were used to quantify the amount of snow and precipitation incorporated into the sea ice cover. Results show that meteoric ice (precipitation transformed to ice) constitute up to 35% of the total sea ice mass, much higher than reported elsewhere. Furthermore, the formation of superimposed ice (refrozen snow melt or rain) seem to be important as well, presumably due to the mild ice climate conditions in the region.The atmospheric load is also important in the chemical budgets of several elements, in particular nitrogen and lead, in the sea ice cover. The sea ice cover acts as a buffer for accumulated substances until its inevitable melt. However, the accumulated nutrients are transported through the ice at times when the ice becomes permeable. This, in turn, makes the accumulated nutrients available in the lower ice layers as well as in under-ice water, potentially affecting algal growth. The chemical budgets and the seasonal cycling of elements with selective rejection/retention during freezing of seawater are potentially affected, especially in the shallow regions of the Bothnian Bay.
Keywords: sea ice; snow-ice; superimposed ice; meteoric ice; chemistry; nutrients; trace elements; Baltic Sea
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Granskog, M. A., Kaartokallio, H., Thomas, D., Ehn, J., Kuosa, H., & Sonninen, E. (2004). Horizontal variations in biogeochemical characteristics of landfast sea ice in the Gulf of Finland (the Baltic Sea). In 21-25 June 2004 Russia S. P. 17th IAHR international symposium on ice (Ed.), (pp. 5–11). Proceedings of the 17th IAHR international symposium on ice, Saint Petersburg, Russia, 21-25 June 2004, 2. International Association of Hydraulic Engineering and Research.
Abstract: In order to study the mesoscale variation in ice properties, horizontal variation of first-year landfast sea ice properties was investigated in the Gulf of Finland, the Baltic Sea. Several scales of variation were considered; samples at spacing of 0.2-, 2- and 20-m were sampled at several locations at different stages of the ice season. Spacing between these locations varied from hundreds of meters to kilometers. The variables measured included salinity, stable oxygen isotopes (δ¹8O), chlorophyll-a, nutrients, and dissolved organic carbon (DOC). Analyses of the data from the arrays did not show evidence of significant patchiness at scales <20-m. On scales of hundreds of meters to kilometers there was clear patchiness in several parameters (salinity, chl-a, snow depth and ice thickness). The results imply that the sampling effort in Baltic Sea ice studies should be concentrated at scales of hundreds of meters to kilometers.
Keywords: Fast Ice; Biogeochemical Properties; Salinity; Oxygen Isotope; Chlorophyll; Nutrients; Doc; Horizontal Patchiness; Spatial Variability; Patchiness; Baltic Sea; Oxygen Isotopes
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Leppäranta, M., Palosuo, E., Grönvall, H., Kalliosaari, S., Seinä, A., & Peltola, J. (Eds.). (1988). Phases of the ice season in the Baltic Sea (North of 57°N). Finnish Mar Res, 254. Helsinki: Finnish Institute of Marine Research.
Keywords: Ice; Ice Extent / Cover; Baltic Sea
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Meiners, K. (2002). Sea-ice communities: structure and composition in Baltic, Antarctic and Arctic seas. Doctoral thesis, Institut für Polarökologie, Universität Kiel, Kiel.
Abstract: Sea ice is an important structural component of polar marine ecosystems but also at lower latitude seas like e.g. the northern Baltic Sea. This study summarises observations on biological, chemical and physical characteristics of sea ice and under-ice water obtained during three expeditions to the Baltic Sea, the Fram Strait area (Arctic) and the Bellingshausen Sea (Antarctica). The study aimed at a better understanding and quantification of different components of the sea ice related food web. The seasonal Baltic sea ice is least studied and therefore the work in this area focused on an inventory determination of the abundance and biomass composition of the sympagic (=ice-associated) community of the Bothnian Bay and Bothnian Sea as well as on the importance of abiotic and biotic factors in the control of ice algal accumulation. The work on the better explored polar sea ice focused on the abundance, distribution and characteristics of transparent exopolymer particles (TEP) in Arctic and Antarctic sea ice. TEP are a recently described class of exopolymeric particles, which are formed abiotically and biotically from polysaccharid-rich precursors. High amounts of TEP-precursors are released by bacteria and algae especially in response to environmental stress. In the pelagic realm TEP are important in the aggregation of diatom blooms, provide the matrix of macroaggregates and serve as substrate and habitat for attached bacteria. High concentrations of TEP have been recently described for Arctic sea ice and may have an important impact on carbon dynamics in sea-ice systems. The present study related TEP concentrations to biotic and abiotic sea ice parameters, potential modes of TEP formation were elucidated and the importance of TEP for the sea-ice habitat was discussed.
Keywords: Baltic Sea
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Mälkki, P., & Tamsalu, R. (1985). Physical features of the Baltic Sea. Finnish Mar Res, 252. Helsinki: Finnish Institute of Marine Research.
Keywords: Baltic Sea; Bottom Topography; Climate; Salinity; Temperature; Ice; Ice Extent / Cover
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