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Author Gerland, S; Winther, J-G; Örbæk, JB; Ivanov, BV
Title Physical properties, spectral reflectance and thickness development of first year fast ice in Kongsfjorden, Svalbard Type Book Chapter
Year 1999 Publication Proceedings of the International Symposium on Polar Aspects of Global Change Abbreviated Journal
Volume Issue Pages 275-282
Keywords Fast ice; Ice properties; Reflectance; Ice thickness; Physical properties; PNE, Norway, Svalbard, Kongsfjorden
Abstract A ground truth study was performed on first year fast ice in Kongsfjorden, Svalbard, during spring 1997 and 1998. The survey included sea ice thickness monitoring as well as observation of surface albedo, attenuation of optical radiation in the ice, physical properties and texture of snow and sea ice. The average total sea ice thickness in May was about 0.9 m, including a 0.2 m thick snow layer on top. Within a few weeks in both years, the snow melted almost completely, whereas the ice thickness decreased by not more than 0.05 m. During spring, the lower part of the snow refroze into a solid layer. The sea ice became more porous. Temperatures in the sea ice increased and the measurable salinity of the sea ice decreased with time. Due to snow cover thinning and snow grain growth, maximum surface albedo decreased from 0.96 to 0.74. Texture analysis on cores showed columnar ice with large crystals (max. crystal length > 0.1 m) below a 0.11 m thick mixed surface layer of granular ice with smaller crystals. In both years, we observed sea ice algae at the bottom part of the ice. This layer has a significant effect on the radiation transmissivity.
Address Norwegian Polar Institute, Polar Environmental Centre, N-9296 Tromsoe, Norway
Corporate Author Thesis (up)
Publisher Norsk Polarinstitutt Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Polar Research Abbreviated Series Title Polar Res
Series Volume 18 Series Issue 2 Edition
ISSN 0800-0395 ISBN Medium
Area Expedition Conference International Symposium on Polar Aspects of Global Change, Tromso (Norway), 24-28 Aug 1998
Notes Conference Approved no
Call Number refbase @ user @ 726 Serial 6
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Author Granskog, M.; Kaartokallio, H.; Kuosa, H.; Thomas, D.N.; Vainio, J.
Title Sea ice in the Baltic Sea – A review Type Journal Article
Year 2006 Publication Estuarine, Coastal and Shelf Science Abbreviated Journal Estuar Coast Shelf Sci
Volume 70 Issue 1-2 Pages 145-160
Keywords sea ice; Baltic Sea; biogeochemistry; plankton; seasons
Abstract Although the seasonal ice cover of the Baltic Sea has many similarities to its oceanic counterpart in Polar Seas and Oceans, there are many unique characteristics that mainly result from the brackish waters from which the ice is formed, resulting in low bulk salinities and porosities. In addition, due to the milder climate than Polar regions, the annual maximum ice extent is highly variable, and rain and freeze-melt cycles can occur throughout winter. Up to 35% of the sea ice mass can be composed from metamorphic snow, rather than frozen seawater, and in places snow and superimposed ice can make up to 50% of the total ice thickness. There is pronounced atmospheric deposition of inorganic nutrients and heavy metals onto the ice, and in the Bothnian Bay it is estimated that 5% of the total annual flux of nitrogen and phosphorus and 20–40% of lead and cadmium may be deposited onto the ice fields from the atmosphere. It is yet unclear whether or not the ice is simply a passive store for atmospherically deposited compounds, or if they are transformed through photochemical processes or biological accumulation before released at ice and snow melt.As in Polar sea ice, the Baltic ice can harbour rich biological assemblages, both within the ice itself, and on the peripheries of the ice at the ice/water interface. Much progress has been made in recent years to study the composition of these assemblages as well as measuring biogeochemical processes within the ice related to those in underlying waters. The high dissolved organic matter loading of Baltic waters and ice result in the ice having quite different chemical characteristics than those known from Polar Oceans. The high dissolved organic material load is also responsible in large degree to shape the optical properties of Baltic Sea ice, with high absorption of solar radiation at shorter wavelengths, a prerequisite for active photochemistry of dissolved organic matter.Land-fast ice in the Baltic also greatly alters the mixing characteristics of river waters flowing into coastal waters. River plumes extend under the ice to a much greater distance, and with greater stability than in ice-free conditions. Under-ice plumes not only alter the mixing properties of the waters, but also result in changed ice growth dynamics, and ice biological assemblages, with the underside of the ice being encased, in the extreme case, with a frozen freshwater layer.There is a pronounced gradient in ice types from more saline ice in the south to freshwater ice in the north. The former is characteristically more porous and supports more ice-associated biology than the latter. Ice conditions also vary considerably in different parts of the Baltic Sea, with ice persisting for over half a year in the northernmost part of the Baltic Sea, the Bothnian Bay. In the southern Baltic Sea, ice appears only during severe winters.
Address
Corporate Author Thesis (up)
Publisher Elsevier Science BV Place of Publication Amsterdam Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0272-7714 ISBN Medium
Area Expedition Conference
Notes Review Approved no
Call Number refbase @ admin @ Granskog_etal2006 Serial 14
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Author Granskog, M.A.; Kaartokallio, H.; Kuosa, H.; Thomas, D.N.; Ehn, J.; Sonninen, E.
Title Scales of horizontal patchiness in chlorophyll a, chemical and physical properties of landfast sea ice in the Gulf of Finland (Baltic Sea) Type Journal Article
Year 2005 Publication Polar Biology Abbreviated Journal Polar Biol
Volume 28 Issue 4 Pages 276-283
Keywords
Abstract Horizontal variation of first-year landfast sea ice properties was studied in the Gulf of Finland, the Baltic Sea. Several scales of variation were considered; a number of arrays with core spacings of 0.2, 2 and 20 m were sampled at different stages of the ice season for small-scale patchiness. Spacing between these arrays was from hundreds of meters to kilometers to study mesoscale variability, and once an onshore&#150;offshore 40-km transect was sampled to study regional scale variability. Measured variables included salinity, stable oxygen isotopes (δ¹8O), chlorophyll a (chl-a), nutrients and dissolved organic carbon. On a large scale, a combination of variations in the under-ice water salinity (ice porosity), nutrient supply and the stage of ice development control the build-up of ice algal biomass. At scales of hundreds of meters to kilometers, there was significant variability in several parameters (salinity, chl-a, snow depth and ice thickness). Analyses of the data from the arrays did not show evidence of significant patchiness at scales <20 m for algal biomass. The results imply that the sampling effort in Baltic Sea ice studies should be concentrated on scales of hundreds of meters to kilometers. Using the variations observed in the study area, the estimate for depth-integrated algal biomass in landfast sea ice in the Gulf of Finland (March 2003) is 5.5±4.4 mg chl-a m-².
Address
Corporate Author Thesis (up)
Publisher Springer-Verlag Place of Publication Heidelberg Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0722-4060 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ admin @ Granskog_etal2005 Serial 15
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Author Granskog, M.A.; Kaartokallio, H.; Thomas, D.; Ehn, J.; Kuosa, H.; Sonninen, E.
Title Horizontal variations in biogeochemical characteristics of landfast sea ice in the Gulf of Finland (the Baltic Sea) Type Book Chapter
Year 2004 Publication Abbreviated Journal
Volume Issue Pages 5-11
Keywords Fast Ice; Biogeochemical Properties; Salinity; Oxygen Isotope; Chlorophyll; Nutrients; Doc; Horizontal Patchiness; Spatial Variability; Patchiness; Baltic Sea; Oxygen Isotopes
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.
Address
Corporate Author Thesis (up)
Publisher International Association of Hydraulic Engineering and Research Place of Publication Editor 17th IAHR international symposium on ice, S.P., Russia, 21-25 June 2004,
Language Summary Language Original Title
Series Editor Series Title Proceedings of the 17th IAHR international symposium on ice, Saint Petersburg, Russia, 21-25 June 2004 Abbreviated Series Title
Series Volume 2 Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ admin @ Granskog_etal2004 Serial 16
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Author Granskog, M.A.; Kaartokallio, H.; Thomas, D.N.; Kuosa, H.
Title Influence of freshwater inflow on the inorganic nutrient and dissolved organic matter within coastal sea ice and underlying waters in the Gulf of Finland (Baltic Sea) Type Journal Article
Year 2005 Publication Estuarine, Coastal and Shelf Science Abbreviated Journal Estuar Coast Shelf Sci
Volume 65 Issue 1-2 Pages 109-122
Keywords coastal oceanography; sea ice; river plumes; estuarine chemistry; nutrients (mineral); dissolved organic matter; Baltic Sea
Abstract A study was conducted to measure the biogeochemical characteristics of freshwater plumes underlying Baltic Sea land-fast ice, and the overlying sea ice. A 40-km long transect was conducted in the northern Baltic Sea in March 2003, following a freshwater plume from its source into the fully mixed open-sea area. The spreading of river outflow below the ice resulted in a well-stratified low-salinity surface layer further out than normally occurs in the open-water period. The freshwaters were high in dissolved organic matter (DOC, DON and CDOM), and inorganic nutrients (ammonium, nitrate and silicate), although the levels of phosphate were low. In general these parameters changed concurrently with salinity in such a way that mixing was conservative. The characteristics of the ice varied from the freshwater source to the open water, with increasing salinity and brine volumes (porosity) occurring in the more open-sea stations. Coinciding with the changes in ice properties there was an increase in sea-ice algal growth in the more marine stations along the transect. Biological activity in the ice was largely confined to bottom ice assemblages. In contrast to the conditions in the underlying water, no relationship between salinity, inorganic nutrients and organic matter was observed in the ice. In particular ammonium, phosphate, DOC and DON were present in excess of those levels predicted from the dilution curves, indicating the presence of considerable DOM production by ice assemblages, inorganic nutrient uptake and remineralization within the ice.
Address
Corporate Author Thesis (up)
Publisher Academic Press Place of Publication San Diego Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0272-7714 ISBN Medium
Area Expedition Conference
Notes Sampling: Nine stations along a 40km salinity gradient from inner Pojo Bay through the Archipelago to the edge of the open sea Approved no
Call Number refbase @ admin @ Granskog_etal2005_2 Serial 17
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