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Number of results: 4
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Abstract

Investigations of the snow cover at the end of the winter 1990/1991 were carried out in several areas in West Spitsbergen, namely, Lomonosovfonna, Kongsvegen, Fridtjovbreen, Amundsenisen and that north of the Hornsund Fjord. The physical properties and chemical nature of precipitation and the snow cover were determined. The studies revealed high variation in the precipitation and the thickness of the snow cover: 317 mm w.e. (water equivalent) in the Hornsund area, 659 mm w.e. at Lomonosovfonna, 1076 mm w.e. at Fridtjovbreen and 1716 mm w.e. at Amundsenisen. The salt loads deposited in the snow cover in different parts of West Spitsbergen were also calculated (2.8 t/km2 at Lomonosovfonna, 15.8 t/km2 at Kongsvegen and 43.2 t/km2 at Amundsenisen). An intensive process of demineralisation during the conversion of snow to firn was revealed, reaching as much as 90% during the first summer. An attempt to determine the anthropogenic element content using the pH values for the precipitation and snow cover was also made. A distinct correlation between the physico-chemical characteristic of snow layer and falling snow was found. On the basis of the quality of the precipitation and snow cover, West Spitsbergen has been classified into following provinces: (1) northern situated within Arctic High (Lomonosovfonna and Kongsvegen), (2) southern ndergoing mainly moving air masses from the Arctic High and Greenland Low (Amundsenisen and Hornsund region).
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Abstract

Properties of a snow cover in the vicinity of Arctowski Station, King George Island (West Antarctica) were studied in 1991. Variations of snow quality and physical transformations were analysed against changes of atmospheric parameters, basing on water equivalent index and repeatable examination of snow pits. Essential dependence of snow cover distribution and snow structure from local climatic features and terrain morphology was found. Thawing occurs in the whole mass of snow, with its contribution of both liquid and gas water phases.
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Abstract

This paper presents a detailed study of melting processes conducted on Hansbreen - a tidewater glacier terminating in the Hornsund fjord, Spitsbergen. The fieldwork was carried out from April to July 2010. The study included observations of meltwater distribution within snow profiles in different locations and determination of its penetration time to the glacier ice surface. In addition, the variability of the snow temperature and heat transfer within the snow cover were measured. The main objective concerns the impact of meltwater on the diversity of physical characteristics of the snow cover and its melting dynamics. The obtained results indicate a time delay between the beginning of the melting processes and meltwater reaching the ice surface. The time necessary for meltwater to percolate through the entire snowpack in both, the ablation zone and the equilibrium line zone amounted to c. 12 days, despite a much greater snow depth at the upper site. An elongated retention of meltwater in the lower part of the glacier was caused by a higher amount of icy layers (ice formations and melt-freeze crusts), resulting from winter thaws, which delayed water penetration. For this reason, a reconstruction of rain-on-snow events was carried out. Such results give new insight into the processes of the reactivation of the glacier drainage system and the release of freshwater into the sea after the winter period.
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Abstract

The Antarctic Peninsula region has experienced a recent cooling for about 15 years since the beginning of the 21st century. In Livingston Island, this cooling has been of 0.8°C over the 12-yr period 2004–2016, and of 1.0°C for the summer average temperatures over the same period. In this paper, we analyse whether this observed cooling has implied a significant change in the density of the snowpack covering Hurd and Johnsons glaciers, and whether such a density change has had, by itself, a noticeable impact in the calculated surface mass balance. Our results indicate a decrease in the snow density by 22 kg m-3 over the study period. The density changes are shown to be correlated with the summer temperature changes. We show that this observed decrease in density does not have an appreciable effect on the calculated surface mass balance, as the corresponding changes are below the usual error range of the surface mass balance estimates. This relieves us from the need of detailed and time-consuming snow density measurements at every mass-balance campaign.
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