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Number of results: 22
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Abstract

Three types of rock glaciers (moraine, cirque and subslope ones) were distinguished in northwestern Wedel Jarlsberg Land. Subslope rock glaciers were found different from nival moraines. A development of subslope and fossil cirque rock glaciers was connected with the older Holocene whereas of active cirque and moraine rock glaciers with the Little Ice Age.
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Abstract

Water bears (Tardigrada) are known as one of the most extremophile animals in the world. They inhabit environments from the deepest parts of the oceans up to the highest mountains. One of the most extreme and still poorly studied habitats which tardigrades inhabit are cryoconite holes. We analysed the relation between area, depth, elevation and tardigrades densities in cryoconite holes on four glaciers on Spitsbergen. The mean (±SD) of cryoconite area was 1287.21±2400.8 cm2, while the depth was on average 10.8±11.2 cm, the elevation 172.6±109.66 m a.s.l., and tardigrade density 24.9±33.0 individuals per gram of wet material (n = 38). The densities of tardigrades on Hans Glacier reached values of up to 168 ind. cm3, 104 ind. g-1 wet weight, and 275 ind. g-1 dry weight. The densities of tardigrades of the three glaciers in Billefjorden were up to 82 ind. cm2, 326 ind. g-1 wet weight and 624 ind. g-1 dry weight. Surprisingly, although the model included area, depth and elevation as independent variables, it cannot explain Tardigrada density in cryoconite holes. We propose that due to the rapid melting of the glacier surface in the Arctic, the constant flushing of cryoconite sediments, and inter-hole water-sediment mixing, the functioning of these ecosystems is disrupted. We conclude that cryoconite holes are dynamic ecosystems for microinvertebrates in the Arctic.
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Abstract

Spitsbergen glaciers react rapidly to changes in the polar environment, which is expressed in differences in extent of their fronts and surface geometry. The Scott Glacier, which is situated in the NW part of Wedel Jarlsberg Land, is an example of the glacier that has undergone almost continuous recession since the Little Ice Age, interrupted by surges. The variations in recession are characterised based on multiannual data with particularly consideration of the period 1990–2005 and the season 2005/2006. Acceleration of front recession and lowering the surface was found only within the tongue up to a height of about 220 m a.s.l. Whereas, in the area situated in the zone of rock steps and above in the ablation zone, the change of glacier surface ablation (Dh) has been recorded compared to the mean annual recession for the period 1990–2005. Moreover, for the upper firn field, the positive surface ablation (DhS7 = +0.19 m) was observed. As the result of progressive reduction of the Scott Glacier mass, with the participation of other factors (bedrock relief among others), new surfaces of roche moutonnée are uncovering particularly in the tongue zone.
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Abstract

Although the terrestrial marginal zones of some glaciers on Spitsbergen are relatively well described, we are largely ignorant about the morphology of their submarine forefields. Initial reconnaissance of the forefields of the Aavatsmark and Dahl glaciers in the Kaffiøyra region and soundings made in that of the Hans Glacier (southern Spitsbergen ) indicate the occurrence of sea-floor push-moraines which can be as much as 3 m high. Their lateral separation is considered to denote annual recession rates. They appear to result from cyclical annual advances of ice-cliffs during winters when the deposits are risen up at the contact of the ice with the sea-floor. The development of the major forms may be related to surge. There is some evidence that certain elements in the sea-bed morphology date from the Little Ice Age (LIA).
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Abstract

The radar device for measurement of thickness and structure of "warm" glaciers was used in this work. The measurement of thickness of dielectric is based here on the examination of transit time of hight frequency electromagnetic pulse throught the measured stratum. A total ice volume of "warm" glaciers is in the melting temperature here. Such glaciers are characterized by a large number of internal structure defects. The electromagnetic wave reflections are caused not only b the glacier base but, additionally by ice crevasses, more imbided water layers and by all other defects of the internal glacier structure, too. The simple statistical method was elaborated for differentiation of essential layers reflections from random reglections caused by less extented objects. This method was used to obtain the two transversal profiles of the Hans Glacier (South Spitsbergen).
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Abstract

Traditional mass balance measurements by stake readings and snow surveying have been conducted annually since 1996 on the Waldemar Glacier (= Waldemarbreen) in northwest Spitsbergen, Svalbard. Several indirect methods were also used for estimating its mass balance. These methods were divided into two major groups: climatological and geodetic. A comparison of the latest map (2000) with that of 1978 and climatological records enable us to calculate the change in the mass balance of Waldemarbreen over 34 years. These methods include air temperature and degree-day (PDD) models. The average mass balance of Waldemarbreen, computed by climatological methods, was -0.42 m a-1 of water equivalent (w.e.) for the period 1970-2004, and -0.51 m w.e. for 1996-2004. These balances were compared with the glaciological balance for the period 1996-2004, -0.53 m w.e.. The mass balance was also computed using geodetic method, giving -0.52 m of w.e. from 1978 to 2000. It is suggested that, from these results, the approach used for Waldemarbreen might be also useful for estimation the mass balances of other small Svalbard glaciers which terminate on land.
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Abstract

Glacierized fjords are dynamic regions, with variable oceanographic conditions and complex ice−ocean interactions, which are still poorly understood. Recent studies have shown that passive underwater acoustics offers new promising tools in this branch of polar research. Here, we present results from two field campaigns, conducted in summer 2013 and spring 2014. Several recordings with a bespoke two−hydrophone acoustic buoy were made in different parts of Hornsund Fjord, Spitsbergen in the vicinity of tidewater glaciers to study the directionality of underwater ambient noise. Representative segments of the data are used to illustrate the analyses, and determine the directions of sound sources by using the time differences of arrivals between two horizontally aligned, broadband hydrophones. The results reveal that low frequency noise (< 3 kHz) is radiated mostly from the ice cliffs, while high−frequency (> 3 kHz) noise directionality strongly depends on the distribution of floating glacial ice throughout the fjord. Changing rates of iceberg production as seen for example in field photographs and logs are, in turn, most likely linked to signal amplitudes for relevant directions. These findings demonstrate the potential offered by passive acoustics to study the dynamics of individual tidewater glaciers.
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Abstract

Arctic glaciers depend on supply of moisture, mostly from the Atlantic. The snowline is remarkably high in northeast Siberia, remote from this source. Because of differential solar radiation receipt, local glaciers have a northward−facing tendency throughout the Arctic. This is weaker than in dry mid−latitudes but low sun angles enhance the effects of shading, compensating for the broader range of aspects ( i.e. slope directions) illuminated in summer. Statistics from the World Glacier Inventory and other sources show that mass balance differences between slopes of different aspects give both more glaciers, and lower glaciers, facing the favoured direction: usually North. This is clear, for example, for local glaciers (and for all small glaciers) in central Spitsbergen and in Axel Heiberg Island. Wind effects (drifting snow to leeward slopes) are much less important, except in northwest Europe from Norway to Novaya Zemlya which is under the strong influence of westerly winds, greatest in the Polar and Sub−polar Urals. A thorough analysis is provided of aspect data for local glaciers within and near the Arctic Circle, and of variation in glacier mid−altitude with aspect and position. There is consistency between mean glacier aspect (in terms of numbers) and aspect with lowest glaciers, everywhere except in Wrangel Island.
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Abstract

A section of a gravel−dominated coast in Isbjørnhamna (Hornsund, Svalbard) was analysed to calculate the rate of shoreline changes and explain processes controlling coastal zone development over last 50 years. Between 1960 and 2011, coastal landscape of Isbjørnhamna experienced a significant shift from dominated by influence of tide−water glacier and protected by prolonged sea−ice conditions towards storm−affected and rapidly changing coast. Information derived from analyses of aerial images and geomorphological mapping shows that the Isbjørnhamna coastal zone is dominated by coastal erosion resulting in a shore area reduction of more than 31,600 m 2 . With ~3,500 m 2 of local aggradation, the general balance of changes in the study area of the shore is negative, and amounts to a loss of more than 28,000 m 2 . Mean shoreline change is −13.1 m (−0.26 m a −1 ). Erosional processes threaten the Polish Polar Station infrastructure and may damage of one of the storage buildings in nearby future.
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Abstract

The near-surface ice thermal structure of the Waldemarbreen, a 2.5-square km glacier located at 78°N 12°E in Spitsbergen, Svalbard , is described here. Traditional glaciological mass balance measurements by stake readings and snow surveying have been conducted annually since 1996. The near-surface ice temperature was investigated with automatic borehole thermistors in the ablation and accumulation areas in 2007-2008. The mean annual surface ice temperatures (September-June) of the ablation area were determined to be -4.7°C at 1 m depth and -2.5°C at 9 m . For the accumulation area, they were -3.0°C at 2 m , and -2.3°C at 10 m depth between September and August. On the Waldemarbreen, at 10 m depth, the mean annual near-surface ice temperature was 4.0°C above the mean annual air temperature in the accumulation area. The Waldemarbreen may thus be classified as a polythermal type with cold ice which is below the pressure melting point and a temperate ice layer in the bottom sections of the glacier and with a temperate surface layer only during summer seasons. At a depth of 10 m , temperatures are of the order of -2°C to -3°C.
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Abstract

The purpose of this study is to describe the current state of tidewater glaciers in Svalbard as an extension of the inventory of Hagen et al. (1993). The ice masses of Svalbard cover an area of ca 36 600 km2 and more than 60% of the glaciated areas are glaciers which terminate in the sea at calving ice-cliffs. Recent data on the geometry of glacier tongues, their flow velocities and front position changes have been extracted from ASTER images acquired from 2000-2006 using automated methods of satellite image analysis. Analyses have shown that 163 Svalbard glaciers are of tidewater type (having contact with the ocean) and the total length of their calving ice-cliffs is 860 km . When compared with the previous inventory, 14 glaciers retreated from the ocean to the land over a 30-40 year period. Eleven formerly land-based glaciers now terminate in the sea. A new method of assessing the dynamic state of glaciers, based on patterns of frontal crevassing, has been developed. Tidewater glacier termini are divided into four groups on the basis of differences in crevasse patterns and flow velocity: (1) very slow or stagnant glaciers, (2) slow-flowing glaciers, (3) fast-flowing glaciers, (4) surging glaciers (in the active phase) and fast ice streams. This classification has enabled us to estimate total calving flux from Svalbard glaciers with an accuracy appreciably higher than that of previous attempts. Mass loss due to calving from the whole archipelago (excluding Kvitřya) is estimated to be 5.0-8.4 km3 yr-1 (water equivalent - w.e.), with a mean value 6.75 ± 1.7 km3 yr-1 (w.e.). Thus, ablation due to calving contributes as much as 17-25% (with a mean value 21%) to the overall mass loss from Svalbard glaciers. By implication, the contribution of Svalbard iceberg flux to sea-level rise amounts to ca 0.02 mm yr-1. Also calving flux in the Arctic has been considered and the highest annual specific mass balance attributable to iceberg calving has been found for Svalbard.
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Abstract

Marine rock-accumulative terraces at 2-230 m a.s.l. in the southern Sörkapp Land are typical for glacioisostaticly uplifted areas. The Holocene terraces reach up to 19 m a.s.l. An outstanding coastal ridge at 9-10 m a.s.l. was radiocarbon-dated at 6580±160 years B.P. No marine transgression during the Holocene on higher and older terraces was noted, what is also confirmed by well preserved raised storm ridges. Any of glacial advances during the Holocene were more extensive than the one of the Little Ice Age. However the Pleistocene glaciations were more extensive. Among glacial landforms in the area there are: ice-cored frontal and lateral moraines up to 70 m high, plains of ground, ablation and fluted moraines, complexes of glaciofluvial fans. The glaciers retreated 0.3-2 km since 1936 i.e. ca 10 m a year on the average. There are large consequent structural landslides on eastern slopes of Keilhaufjellet.
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Abstract

Reduced ice thickness made the glaciers of the northeastern Sörkapp Land occupy considerably smaller area in 1971 than in 1961. Glacial retreat was however more limited in this area than in a remaining part of the Sörkapp Land. Melting of firn intensified processes on mountain slopes.
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Abstract

The ablation of glaciers is an important factor in energy exchange between the atmosphere and land ice masses. The dynamics of ablation closely reflects climate changes and is important for the estimation of the outflow of meltwater, which, having penetrated a glacier to bedrock, stimulates its velocity by increasing basal sliding. More detailed studies using automatic weather stations (AWS) and the calculation of the energy budget are rarely conducted on small glaciers. The mass balance of the Hans Glacier has been monitored since 1989. Its intensified monitoring using AWS began in 2003. The results show that ablation depends more evidently on the daily mean and maximum air temperature and wind speed than on total and net radiation. Ablation, both that controlled by sonic height ranger and that measured manually on stakes, was compared with the values calculated on the basis of energy flux formulas applied by Oerlemans (2000). The statistical results allowed us to construct empirical equations, which in turn enabled us to compute the course and total ablation during the summer seasons. It can be described on the basis of two primary meteorological elements (air temperature and wind speed), as recorded in the station representing the regional area (Hornsund) or measured in situ on the glacier. Standard measurements of ablation from the years 1989-2004 were used to verify empirical model. The computed mean value of summer ablation for 1989-2004 was calculated at 1.35 m , differing from real measurements by only 10% (with SD = 0.18). The results obtained illustrate that an empirical equation can be applied in time series analyses. A regional ablation model enables us to investigate the mass-balance history of glaciers on the basis of meteorological data.
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Abstract

In summer 1998 detailed measurements of ablation were carried out on the Waldemar Glacier in order to determine its spatial and time variation. Five-days' average ablation was equal to 14.7 cm water equivalent (w.e.), with maximum total ablation of 160-180 cm w.e. at 200 m a.s.l., and the lowest ablation of 106 cm w.e. at 350 m a.s.l. Total ablation for the whole glacier was estimated at 120.5 cm w.e. Simplified scheme of changes of summer ablation with altitude was exampled by this glacier. Relation between discharge from individual fragments of the Waldemar Glacier and their ablation was examined. Discharge of the Waldemar River was analysed: from about 4,800,000 m3 of water in the stream, 67% came from surface ablation of the Waldemar Glacier.
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Abstract

One of the most significant global climatic events in the Cenozoic was the transition from greenhouse to icehouse conditions in Antarctica. Tectonic evolution of the region and gradual cooling at the end of Eocene led to the first appearance of ice sheets at the Eocene/Oligocene boundary (ca. 34 Ma). Here we report geological record of mountain glaciers that preceded major ice sheet formation in Antarctica. A terrestrial, valley-type tillite up to 65 metres thick was revealed between two basaltic lava sequences in the Eocene– Oligocene Point Thomas Formation at Hervé Cove – Breccia Crag in Admiralty Bay, King George Island, South Shetland Islands. K-Ar dating of the lavas suggests the age of the glaciation at 45–41 Ma (Middle Eocene). It is the oldest Cenozoic record of alpine glaciers in West Antarctica, providing insight into the onset of glaciation of the Antarctic Peninsula and South Shetland Islands.
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Abstract

Arctic glaciers respond quickly to climatic conditions, which is why they play a special role as climate warming indicators. Studying them in the long term is the key to understanding future global environmental changes.
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Abstract

Soils, having a well-developed sequence of A and Bw horizons, are widespread on the uplifted marine terrace 8- 12 m a.s.l. in the proximity of Nottinghambukta Bay . The present-day origin of these soils is however questionable, while similarly developed soils, but buried under the cover of the youngest till were found on a forefield of the Werenskiold Glacier. To quantify an intensity of the soil-forming process under present climate conditions of SW Spitsbergen , the chronosequence of soils developed from the Recent, up to 70 year-old moraines, was studied on the forefield of Werenskiold Glacier. Significant dissolution of CaCO3, decrease of pH, leaching of calcium and magnesium, increase of amorphous iron content, as well as an accumulation of organic matter and initial formation of aggregate soil structure were observed within the surface layer of recent till. The 70 year-long period of pedogenesis was, however, too short for a distinct morphological differentiation of the subsurface B horizon. It is concluded, that deep and structural Bw horizons of some surface and buried soils are relicts of a much longer period of relatively warm climate before the last transgression of glaciers.
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Abstract

This study used ground penetrating radar soundings to examine a tongue-shaped rock glacier (64°04’S 58°25’W) on James Ross Island, Antarctic Peninsula, in January 2005. The rock glacier studied has multiple well-developed transverse ridges and approximately 800 m long from the talus of its head to its frontal slopes and is 300 m wide in the middle. The longitudinal ground penetrating radar profile identified debris bands which dip up-glacier, similar to the thrust structures in the compression zone of a valley glacier. Transverse ground penetrating radar profiles indicated a layered structure which is inclined towards the central part of the rock glacier and which resembles the transverse foliation of a valley glacier. Consequently, the internal structure of the rock glacier is revealed as being similar to the “nested spoons” common in the interior of valley glaciers. We concluded that this rock glacier has been created by the deformation of a glacier ice core and a thick and continuous debris mantle.
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Abstract

The general objective of this research has been to identify the factors and conditions of migration of CaCO3 within glaciers and their marginal zones in Svalbard . Special attention has been paid to the cryochemical processes responsible for precipitation of calcium carbonate in icing (naled ice) formed near fronts of polythermal glaciers during winter. Estimates of the importance of those processes in respect of the general mineral mass transfer in the glacier system are attempted here. Field studies concerning the carbonate contents in proglacial sediments and icing fields were carried out in the Werenskioldbreen and the Elisebreen basins (S and NW Spitsbergen respectively). A functional model of CaCO3 migration in a glacier system is proposed which indicates the various paths of the mineral mass flow. Considerations on intensity of glacial processes permitted quantitative estimation of the particular components in respect to the Werenskioldbreen basin. Cryochemical processes do not appear to be of overriding importance in such migration but, clearly, they play a specific role in retaining CaCO3 in the proglacial zone on land. The crystalline forms present in the icings, which have many lattice defects, are very easily re-dissolved or removed by wind.
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Abstract

Studies of a snow cover on the Waldemar Glacier have been carried out during three spring seasons. In spite of its small area, there is considerable spatial variation in snow deposition on the Waldemar Glacier, different during successive seasons. Winter snow accumulation was the highest in 1995/96 (75 cm in water equivalent), but almost similar in 1996/97 and 1997/98, equal to 48 cm and 42 cm w.e., respectively. Snow cover shows specific physico-chemical features, with many sorts of snow different in its structure, hardness, density and moistening. All analysed snow profiles comprised layers of different grain size and hardness. Volume of water trapped in naledies was estimated to about 457,000 m3 in May 1998. The average winter runoff from the glacier was estimated to 0.024 m3/s i.e. about 91/s.km2.
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Abstract

A glacier lake outburst flood occurred on James Ross Island, Antarctic Peninsula region, during the 2004-2005 austral summer season. The source lake was located on the Lachman II ice-cored rock glacier, and formed prior to 1980. The size of the lake has been increasing gradually since the 1990s. The lake basin extended to approximately 220 m in length and 160 m in width by the end of February 2005. We observed that the lake had drained by February 2005, and found a deep gully on the south side of the lake rim. It appears that the lake level rose and water overflowed the lake rim here. James Ross Island contains a large number of debris-covered glaciers, ice-cored moraines, and rock glaciers with glacier lakes which are dammed by these features or which form upon them. As climatic warming has recently been reported for this region, further glacier lake outburst floods seem likely to occur.
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