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  • 1
    Electronic Resource
    Electronic Resource
    Snow research in Svalbard–an overview (2003)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 22 (2003), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: This paper summarizes the most significant snow-related research that has been conducted in Svalbard. Most of the research has been performed during the 1990s and includes investigations of snow distribution, snow-melt, snow pack characteristics, remote sensing of snow and biological studies where snow conditions play an important role. For example, studies have shown regional trends with about 50% higher amounts of snow accumulation at the east coast of Spitsbergen compared to the west coast. Further, the accumulation rates are about twice as high in the south compared to the north. On average, the increase in accumulation with elevation is 97 mm water equivalents per 100 m increase in elevation. Several researchers reported melt rates, which are primarily driven by incoming short-wave radiation, in the range of 10-20 mm/day during spring. Maximum melt rates close to 70 mm/day have been measured. In addition to presenting an overview of research activities, we discuss new, unpublished results in areas where considerable progress is being made. These are i) modelling of snow distribution, ii) modelling of snowmelt runoff and iii) monitoring of snow coverage by satellite imagery. We also identify some weaknesses in current research activities. They are lacks of i) integration between various studies, ii) comparative studies with other Arctic regions, iii) applying local field studies in models that can be used to study larger areas of Svalbard and, finally, iv) using satellite remote sensing data for operational monitoring purposes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.2003.tb00103.x
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  • 2
    Electronic Resource
    Electronic Resource
    Glaciers in Svalbard: mass balance, runoff and freshwater flux (2003)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 22 (2003), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: Gain or loss of the freshwater stored in Svalbard glaciers has both global implications for sea level and, on a more local scale, impacts upon the hydrology of rivers and the freshwater flux to fjords. This paper gives an overview of the potential runoff from the Svalbard glaciers. The freshwater flux from basins of different scales is quantified. In small basins (A 〈 10 km2), the extra runoff due to the negative mass balance of the glaciers is related to the proportion of glacier cover and can at present yield more than 20% higher runoff than if the glaciers were in equilibrium with the present climate. This does not apply generally to the ice masses of Svalbard, which are mostly much closer to being in balance. The total surface runoff from Svalbard glaciers due to melting of snow and ice is roughly 25 ± 5 km3 a−1, which corresponds to a specific runoff of 680 ± 140 mm a−1, only slightly more than the annual snow accumulation. Calving of icebergs from Svalbard glaciers currently contributes significantly to the freshwater flux and is estimated to be 4 ± 1 km3 a−1 or about 110 mm a−1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.2003.tb00104.x
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  • 3
    Electronic Resource
    Electronic Resource
    Surface reflectance of sea ice and under-ice irradiance in Kongsfjorden, Svalbard (2004)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 23 (2004), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: Initial results from a field experiment on fast ice in Kongsfjorden, Svalbard, in March 2002 are presented. We measured surface reflectance and under-ice irradiance using an advanced, portable spectroradiometer sensitive in the visible and near-infrared parts of the electromagnetic spectrum, i.e. 350-1100 nm. Under-ice irradiance (UV-A, UV-B and photosynthetically active radiation [PAR]) was measured down to depths of 7.5 m by vertical profiling using a six-channel radiometer. We also present model results of wavelength-dependent transmittance of radiation through a combined snow and sea ice layer for various thicknesses of snow. Model results show that the snow and sea ice is more transparent for solar radiation in the PAR region (400-700 nm) than at shorter and longer wavelengths. This is confirmed by the field measurements. Even very thin snow layers on top of the sea ice efficiently prevent solar radiation from penetrating the snow–sea ice system. For example, a 5 cm thick snow layer reduces under-ice irradiance in the PAR region with a factor of about 10. Measurements of under-ice UV irradiance show that both UV-A and UV-B irradiance is reduced with a factor of more than 10 at depths of 7.5 m below the ice compared to at the ice-sea water interface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.2004.tb00134.x
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  • 4
    Electronic Resource
    Electronic Resource
    The physical environment of Kongsfjorden–Krossfjorden, an Arctic fjord system in Svalbard (2002)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 21 (2002), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: Kongsfjorden-Krossfjorden and the adjacent West Spitsbergen Shelf meet at the common mouth of the two fjord arms. This paper presents our most up-to-date information about the physical environment of this fjord system and identifies important gaps in knowledge. Particular attention is given to the steep physical gradients along the main fjord axis, as well as to seasonal environmental changes. Physical processes on different scales control the large-scale circulation and small-scale (irreversible) mixing of water and its constituents. It is shown that, in addition to the tide, run-off (glacier ablation, snowmelt, summer rainfall and ice calving) and local winds are the main driving forces acting on the upper water masses in the fjord system. The tide is dominated by the semi-diurnal component and the freshwater supply shows a marked seasonal variation pattern and also varies interannually. The wind conditions are characterized by prevailing katabatic winds, which at times are strengthened by the geostrophic wind field over Svalbard. Rotational dynamics have a considerable influence on the circulation patterns within the fjord system and give rise to a strong interaction between the fjord arms. Such dynamics are also the main reason why variations in the shelf water density field, caused by remote forces (tide and coastal winds), propagate as a Kelvin wave into the fjord system. This exchange affects mainly the intermediate and deep water, which is also affected by vertical convection processes driven by cooling of the surface and brine release during ice formation in the inner reaches of the fjord arms. Further aspects covered by this paper include the geological and geomorphological characteristics of the Kongsfjorden area, climate and meteorology, the influence of glaciers, freshwater supply, sea ice conditions, sedimentation processes as well as underwater radiation conditions. The fjord system is assumed to be vulnerable to possible climate changes, and thus is very suitable as a site for the demonstration and investigation of phenomena related to climate change.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.2002.tb00072.x
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  • 5
    Electronic Resource
    Electronic Resource
    Physical properties, spectral reflectance and thickness development of first year fast ice in Kongsfjorden, Svalbard (1999)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 18 (1999), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: 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 lenght 〉 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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.1999.tb00304.x
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  • 6
    Electronic Resource
    Electronic Resource
    Meltwater production in Antarctic blue-ice areas: sensitivity to changes in atmospheric forcing (1999)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 18 (1999), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: In the near coastal regions of Dronning Maud Land, Antarctica, below-surface ice-melt in blue-ice areas has been observed. The low scattering coefficients of the large-grained blue-ice allow penetration of solar radiation, thus providing an energy source below the ice surface. The sub-surface meltwater is significant enough to show up on remote-sensing imagery in the form of ice-covered lakes. Adjacent snow-accumulation areas have much higher scattering coefficients and consequently limit solar radiation penetration in these regions. These snow and ice surfaces are generally below freezing, and little surface melting occurs. To assess the response of these melt features to changes in atmospheric forcings such as cloudiness, air temperature, and snow accumulation, a physically-based model of the coupled atmosphere, radiation, snow, and blue-ice system has been developed. The model consists of a heat transfer equation with a spectrally-dependent solar-radiation source term. The penetration of radiation into the snow and blue-ice depends on the surface albedo, and the snow and blue-ice grain size and density. Model simulations show that ice melt occurring in this area is sensitive to potential variations in atmospheric forcing. Under certain conditions more traditional surface melting occurs and, under other conditions, the existing melt processes can be shut down completely. In light of the sensitivity of this system to variations in atmospheric forcing, and the ability to view melt-related features using remote sensing, a tool exists to efficiently monitor variations in Antarctic coastal climate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.1999.tb00305.x
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  • 7
    Electronic Resource
    Electronic Resource
    Landsat TM derived and in situ summer reflectance of glaciers in Svalbard (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Polar research 12 (1993), S. 0 
    Details
    ISSN: 1751-8369
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geography , Geosciences
    Notes: The paper presents satellite-derived and in situ reflectance from the Austre Brøggerbreen and Midre Lovenbreen glaciers located 78°50′N, 11°50′E in the Svalbard archipelago. The satellite data are Landsat-5 TM images recorded on 7 August 1987 and 31 August 1988. In situ measurements of shortwave and spectral reflectance of snow, glacier ice and moraine were carried out in August 1991 and in June 1992. In 1987, Austre Brøggerbreen had a positive net mass balance of +0.22 m of water equivalent while the net mass balance in 1988 was negative (-0.52 m). This is reflected in the atmospherically corrected satellite-derived albedo which shows that the reflective characteristics of the ablation and accumulation zones are more uniform and better separated in 1987 than in 1988. Besides the long-term year to year variations of surface albedo, the glaciers show a considerable short-term as well as spatial variability in reflectance. For example, the satellite-derived TM Band 4 albedo was found to vary between 0.19 and 0.65 at Midre Lovenbreen on 31 August 1988. In situ measurements show a drop in daily mean albedo from 0.88 to 0.13 during 4 days at a fixed location on Austre Brøggerbreen in August 1991 (300rn.a.s.l.). Furthermore, spectral measurements of snow albedo in June 1992 clearly demonstrate that the near-infra-red albedo decreases when the snow metamorphoses, i.e. when the characteristic grain size increases. The effect of cloud cover on the snow albedo is also discussed. The integrated albedo (370–900 nm) increased from 0.812 to 0.869 (7%) when the weather condition changed from clear sky to 100% overcast within 2 hours on 9 June 1992. The bidirectional reflectance of snow is measured by taking spectral scans for viewing angles 0° (nadir), 15°, 30°, 45° and 60° for viewing directions facing the sun and at azimuths 90° and 180° away from the sun. The increase in albedo relative to the nadir albedo is found to be 8, 15, 19 and 26% for viewing angles 15°, 30°, 45° and 60°, respectively. The largest anisotropy is seen for metamorphosed snow in measurements facing the sun. Consequently, it may be necessary to correct for the specular properties of snow if satellite-derived surface reflectance is going to be considered in terms of absolute values.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1751-8369.1993.tb00421.x
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  • 8
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    Integrated ocean management for a sustainable ocean economy (2020)
    Springer Nature
    Details
    Publication Date: 2020-08-17
    Electronic ISSN: 2397-334X
    Topics: Biology
    Published by Springer Nature
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  • 9
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    Landsat Thematic Mapper (TM) Derived Reflectance from a Mountainous Watershed during the Snow Melt Season (1992)
    IWA Publishing
    Details
    Publication Date: 1992-10-01
    Print ISSN: 0029-1277
    Electronic ISSN: 2224-7955
    Topics: Architecture, Civil Engineering, Surveying
    Published by IWA Publishing
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  • 10
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    Antarctic Surface and Subsurface Snow and Ice Melt Fluxes (2005)
    American Meteorological Society
    Details
    Publication Date: 2005-05-15
    Description: This paper presents modeled surface and subsurface melt fluxes across near-coastal Antarctica. Simulations were performed using a physical-based energy balance model developed in conjunction with detailed field measurements in a mixed snow and blue-ice area of Dronning Maud Land, Antarctica. The model was combined with a satellite-derived map of Antarctic snow and blue-ice areas, 10 yr (1991–2000) of Antarctic meteorological station data, and a high-resolution meteorological distribution model, to provide daily simulated melt values on a 1-km grid covering Antarctica. Model simulations showed that 11.8% and 21.6% of the Antarctic continent experienced surface and subsurface melt, respectively. In addition, the simulations produced 10-yr averaged subsurface meltwater production fluxes of 316.5 and 57.4 km3 yr−1 for snow-covered and blue-ice areas, respectively. The corresponding figures for surface melt were 46.0 and 2.0 km3 yr−1, respectively, thus demonstrating the dominant role of subsurface over surface meltwater production. In total, computed surface and subsurface meltwater production values equal 31 mm yr−1 if evenly distributed over all of Antarctica. While, at any given location, meltwater production rates were highest in blue-ice areas, total annual Antarctic meltwater production was highest for snow-covered areas due to its larger spatial extent. The simulations also showed higher interannual meltwater variations for surface melt than subsurface melt. Since most of the produced meltwater refreezes near where it was produced, the simulated melt has little effect on the Antarctic mass balance. However, the melt contribution is important for the surface energy balance and in modifying surface and near-surface snow and ice properties such as density and grain size.
    Print ISSN: 0894-8755
    Electronic ISSN: 1520-0442
    Topics: Geography , Geosciences , Physics
    Published by American Meteorological Society
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