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Showing 1 to 16 of 16 for “"Polynya"”.
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HYDROGRAPHIC OBSERVATIONS OF OXYGEN AND RELATED PHYSICAL VARIABLES IN THE NORTH SEA AND WESTERN ROSSSEA POLYNYA investigations using seagliders, historical observations and numerical modelling
… in the North Sea (Europe) and Ross Sea polynya (Antarctica). In particular, this work also focuses on the use of new autonomous underwater vehicles, Seagliders, for oceanographic observations of fine scale (a few metres) to basin-wide features (hundreds of kilometres). Two hydrographic …
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Processes of stratification breakdown and restratification in Antarctic coastal polynyas
Antarctic coastal polynyas are areas of persistent open water surrounded by sea ice. They are characterized by deep winter mixing due to dense water formation from sea ice production and elevated biological productivity after spring restratification. Antarctic coastal polynyas are diverse in terms …
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Processes of Stratification Breakdown and Restratification in Antarctic Coastal Polynyas
Antarctic coastal polynyas are areas of persistent open water surrounded by sea ice. They are characterized by deep winter mixing due to dense water formation from sea ice production and elevated biological productivity after spring restratification. Antarctic coastal polynyas are diverse in terms …
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Modeling the Seasonal Sea Ice Cycle in the Ross Sea, Antarctica
… to investigate Ross Sea seasonal sea ice cycle, polynya dynamics, distribution and transformations of continental shelf water masses, and bottom water formation. Daily atmospheric forcing is from the ECMWF ERA-40 dataset, and for a separate simulation, wind forcing for Terra Nova Bay is …
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Impact of an artifical circulation device on the heat budget of an ice-covered mid-latitude lake
… at nearby Menzies Lake. These effects include polynya development, and a substantial reduction in average temperature. Heat losses due to free convective evaporation and direct snowfall on open water were added to the set of standard aerodynamic formulae used to determine the net meteorological …
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Amundsen Sea sea-ice variability, atmospheric circulation, and spatial variations in snow isotopic composition from new West Antarctic firn cores
… reconstructing Amundsen Sea and Pine Island Bay polynya variability prior to the satellite era. I next investigate the remote influence of tropical Pacific variability on marine aerosol transport to West Antarctica. Results illustrate that both source and transport of marine aerosols to West …
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Air-sea CO2 cycling in the southeastern Beaufort Sea
… paradigm of air–sea CO2 cycling in Arctic polynya regions posited that strong CO2 absorption occurs in the open water seasons, and that a potential outgassing during the winter is inhibited by the sea ice cover. As a new paradigm, we propose that the spatial and temporal variability of many …
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Ice-ocean interactions beneath the north-western Ross Ice Shelf, Antarctica
… strongly influenced by the neighbouring Ross Sea Polynya. High Salinity Shelf Water fills the lower water column continuously, but during summer a southward flow ventilates the cavity bringing Antarctic Surface Water (AASW) to the site. Tides account for half of the flow speed variance, and low …
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Amundsen Sea sea-ice variability, atmospheric circulation, and spatial variations in snow isotopic composition from new West Antarctic firn cores
… reconstructing Amundsen Sea and Pine Island Bay polynya variability prior to the satellite era. I next investigate the remote influence of tropical Pacific variability on marine aerosol transport to West Antarctica. Results illustrate that both source and transport of marine aerosols to West …
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High-latitude sedimentation in response to climate variability during the Cenozoic
… of the West Antarctic Ice Sheet, sea ice/polynya formation, and, notably, the genesis of Antarctic Bottom Water (AABW), a crucial component of the global thermohaline circulation. In Chapter 1, we propose that turbidite currents, arising from the formation of dense shelf water (DSW) in the …
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Tidally Forced Marine Ice Stream Instabilities and Their Consequences
… Dansgaard-Oeschger oscillations, specifically a polynya opening in the Irminger Sea allowing for the exchange of heat between the ocean and atmosphere and the resumption of the Atlantic Meridional Overturning Circulation (AMOC). The fingerprinting of the contributions from all major ice sheets …
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Glaciomarine sedimentation at the continental margin of Prydz Bay, East Antarctica : implications on palaeoenvironmental changes during the Quaternary
… of sea-ice formation in the Cape Darnley polynya. Increased activity of bottom-water flow was reconstructed at transitions from warm to cool conditions, whereas bottom-water activity receded during the mid- Holocene climate optimum. It can be concluded that the Lambert Glacier-Amery Ice …
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Distributions of <i>Euphausia Superba</i>, <i>Euphausia Crystallorophias</i>, and <i>Pleuragramma Antarcticum</i> with Correlations to Environmental Variables in the Western Ross Sea, Antarctica
… in Terra Nova Bay coincides with the coastal polynya, sea ice, cold water temperatures, and slow surface speeds that are needed for their early life stages. The habitat characteristics obtained for the three species provide a basis for projecting potential changes resulting from climate …
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Acoustic diffraction from a semi-infinite elastic plate under arbitrary fluid loading with application to scattering from Arctic ice leads
… ice-covered Arctic waters, where open leads or polynya on the surface represent features from which acoustic energy can be diffracted or scattered. This work focusses on ice as the material for the elastic plate surface, and, though the solution methods presented here have applicability to …
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Development of biomarker-based proxy methods for reconstructing the late Quaternary sea ice history in the Barents Sea
… confirmed the presence of productive polynya throughout this glacial interval. After perennial sea ice and near-zero productivity resulted from the collapse of the Barents Sea Ice Sheet (BSIS) at the onset of Heinrich Stadial 1 (HS1), the ecosystem eventually recovered after rapid ice …
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Development of biomarker-based proxies for paleo sea-ice reconstructions
… which, along with additional local factors (e.g. polynya formation), may have important implications for paleo sea-ice reconstructions. The sedimentary occurrence and distribution of HBI diene II (termed here as IPSO25) were consistent with the recent identification of the diatom Berkeleya …